3-Aza-bicyclof3.3.01octane compounds The present invention relates to novel 3-aza-bicyclo[3.3.0]octane compounds of formula (I) and their use as pharmaceuticals. The invention also concerns related aspects including processes for the preparation of the compounds, pharmaceutical compositions containing one or more compounds of formula (i), and especially their use as orexin receptor antagonists. Orexins (orexin A or OX-A and orexin B or OX-B) are novel neuropeptides found in 1998 by two research groups, orexin A Is a 33 amino acid peptide and orexin B is a 28 amino acid peptide (Sakurai T. et al., Cell, 1998, 92, 573-585). Orexins are produced in discrete neurons of the lateral hypothalamus and bind to G-protein-coupled receptors (OXi and OXa receptors). The orexin-1 receptor (OXi) Is selective for OX-A, and the orexin-2 receptor (OX2) is capable to bind OX-A as well as OX-B. Orexins are found to stimulate food consumption in rats suggesting a physiological role for these peptides as mediators in the central feedback mechanism that regulates feeding behaviour (Sakurai T. et al., Cell, 1998, 92, 573-585). On the other hand, it was also observed that orexins regulate states of sleep and wakefulness opening potentially novel therapeutic approaches to narcolepsy as well as insomnia and other sleep disorders (Chemelli R.M. et al., Cell, 1999,98,437-451). Orexin receptors are found in the mammalian brain and may have numerous implications in pathologies as known from the literature. The present invention provides 3-aza-bicyclo[3.3.0]octane derivatives, which are non-peptide antagonists of human orexin receptors. These compounds are in particular of potential use in the treatment of e.g. eating disorders, drinking disorders, sleep disorders, or cognitive dysfunctions in psychiatric and neurologic disorders. Up to now, several low molecular weight compounds are known having a potential to antagonise either specifically OXi or OX2, or both receptors at the same time. Piperidine derivatives useful as orexin receptor antagonists are disclosed in WO01/g6302. Morpholine derivatives useful as orexin receptor antagonists are disclosed in WO02/44172. /V-AroyI cyclic amine derivatives useful as orexin r«:eptor antagonists are disclosed in WO02/90355. The present invention describes for the first time 3-aza-bicyclo[3.3.0]octane compounds as orexin receptor antagonists. i) A first aspect of the invention consists of a compound of the formula (I) wherein R' represents hydrogen, (C1-4)alkyi or fluorine; R2 represents hydrogen, (C1-4)alkyl or fluorine; R2 represents aryl, which is unsubstituted, mono-, di-, or tri-substituted, wherein the substituents are independently selected from the group consisting of (C1-4)alkyl, (C1-4)alkoxy, trifluoromethyl, trifluoromethoxy, and halogen; or heteroaryl, which is unsubstituted, mono-, di-, or tri-substituted, wherein the substituents are independently selected from the group consisting of (C1-4)alkyl, (C1-4)alkoxy, halogen, and trifluoromethyl; A represents R" represents (C1-4)alkyi, or -NR2R2 R2 represents (Ci-4)alkyl; R® represents hydrogen, or (C1-4)alkyl; R2 represents hydrogen, or (C1-4)aikyl; and D represents aryl, which is unsubstituted, mono-, di-, or tri-substttuted, wherein the substituents are independently selected from the group consisting of (Ci^)alkyl, (C1-4)alkoxy, trifluoromethyl, and halogen. 11) Another embodiment of the invention relates to compounds of formula (I) according to embodiment 1), wherein R2 represents hydrogen, or (C1-4)alkyl; and R2 represents hydrogen, or (C1-4)alkyl. The following paragraphs provide definitions of the various chemical moieties for the compounds according to the invention and are intended to apply unifomily throughout the specification and claims, unless a^ otherwise expressly set out definition provides a broader or narrower definition, i The term "halogen" means fluorine, chlorine, or bromine, preferably fluorine or chlorine. The term "(C1-4)alkyr means a straight-chain or branched-chain alkyl group with 1 to 4 carbon atoms. Examples of (C1-4)alkyl groups are methyl, ethyl, propyl, isopropyl, n-butyl, isobutyl, sec-butyl and tert.-butyl. Preferred are methyl and ethyl. Most preferred is methyl. The term "(C1-4)alkoxy" means a group of the formula (C1-4)alkyl-0- in which the term "(C1-4)alkyl" has the previously given significance. Examples of (CM)alkoxy groups are methoxy, ethoxy, n-propoxy, isopropoxy, n-butoxy, isobutoxy, sec.-butoxy and tert.-butoxy. Preferred are methoxy and ethoxy. Most preferred is methoxy. The term "aryl" means a phenyl, a naphthyl, a 2,3-dlhydro-benzofuranyl-, a ben2o[1,3]dioxolyl-, a 2,3-dihydro-benzo[1,4]dloxinyl-, or a 4W-benzo[1,3Jdtoxinyl group. The aryl group is unsubstituted, mono-, di-, or tri-substituted, wherein the substituents are independently selected from the group consisting of (C1-4)alkyl, (CM)alkoxy, trifluoromethyl, trlfluoromethoxy, and halogen. 2,3-Dlhydro-benzofuranyl-, benzo[1,3]dioxolyl-, 2,3-dihydro-benzo[1,4]dioxlnyl- and 4H-benzo[1,3]dioxinyl groups are preferably unsubstituted. "D" representing "aryl" preferably means phenyl, whk;h is unsubstituted, mono-, di-, or tri-substituted (preferred: mono- or di-substitutec|j, wherein the substiftjents are independently selected from the group consisting of (C1-4)alkyl, (C1-4)alkoxy, trifluoromethyl. and halogen. Examples of "D" representing "aryl" are phenyl, 3-methylphenyl, 4-methylphenyl, 3,4-dimethylphenyl, 4-ethylphenyl, 3-methoxyphenyl, 4-methoxyphenyl, 3-fluorophenyl, 4-fluorophenyl, 3,4-difluorophenyl, 3-chlorophenyl, 4-chlorophenyl, 3-trifluoromethylphenyl and 4-trifluoromethylphenyl. "R3" representing "aryl" preferably means phenyl, which is unsubstituted, mono-, di-, or tri-substituted (preferred: monosubstltuted), wherein the substituente are independently selected from the group consisting (CM)alkyl, (C1-4)alkoxy, trifluoromethyl, trlfluoromethoxy, and halogen (especially methyl, methoxy, fluoro, chloro, bromo, trifluoromethyl and trlfluoromethoxy). Additionally, in another embodiment R2 representing "aryl" means 2,3-dihydro-benzoftjranyl; benzo[1,3]dioxolyl; 2,3-dihydro-benzo[1,4]dioxinyl; or 4W-benzo[1,3]dioxinyl (especially 2,3-dlhydro-ben2o[1,4]dloxlnyl). Examples of R2 representing "aryl" are 2,3-dihydro-benzo[1,4]dioxine-5-yl, 3-methylphenyl, 3-bromophenyl, 3-chlorophenyl, 3-fluorophenyl, 3-methoxyphenyl, 3-trifluoromethoxyphenyl, and 3- trifluoromethylphenyl. In addition to the above-listed i^xampies, a further e}l:kmple is 2,3-dihydro-benzofuranyl. i The term "heteroaryl" means a 5- to 10-membered monocycHc or bicycllc aronatic ring containing 1, 2 or 3 heteroatoms, each independently selected from oxygen, nitrogen and sulfur. Examples of such heteroaryl groups are furanyl, oxazolyl, isoxazolyl, oxadiazolyl, thienyl, thiazolyl, isothiazolyl, thiadiazolyl, pyrrolyl, imidazolyl, pyrazolyl, triazolyl, pyridyl, pyrimidyl, pyridazinyl, pyrazinyl, Indolyl, isoindolyl, benzofuranyl, isobenzofuranyl, benzothiophenyl, Indazolyl, benzimldazolyl, benzoxazolyl, benzisoxazolyl, benzothiazolyl, benzoisothiazolyl, benzotriazolyl, benzoxadlazolyl, benzothiadiazolyl, quinolinyi, isoquinolinyl, naphthyrldinyl, cinnolinyl, quinazollnyl, quinoxalinyl, phthalazinyl, pyrazolo[1,5-alpyridyl, pyrazolo[1,5-a]pyrimidyl, imidazo[1,2-a]pyridyl and imidazo[2,1-b]thiaa)lyl. In addition to the above-listed examples, a further example is pyrrolo{2,1-b]thlazolyl. The above-mentioned heteroaryl groups are unsubstltuted, mono-, di-, or tri-substituted, \Miereln the substituents are independently selected from the group consisting of (Cm)aikyl, (C1-4)alkoxy, halogen, and trifluoromethyl. Preferred heteroaryl groups are i80)»zolyl, pyridyl, indazolyl, benzofuranyl, benzoxazolyl, benzisoxazolyl, benzoisothiazolyl, and imidazo[2,1-b]thiazolyl; and, in addition to the above-listed preferred heteroaryl grcijps. benzothiazolyl, pyrrolo[2,1-b]thiazolyl, and imidazo[1,2-a]pyridlnyl, v^erein the latter three groups fomn a particular sub-embodiment; wherein said groups are unsubstltuted, mono-, di-, or tri-substituted (preferred unsubstltuted, mono-, or di-substituted, most preferred unsubstltuted, or mono-substituted) wherein the substituents are independently selected from the group consisting of (Ciwi)alkyi, (C1-4)alkoxy, halogen, and trifluoromethyl (preferred (CM)aH (CM)alkoxy, and halogen). If substituted, isoxazolyl, indazolyl, benzofuranyl, benzoxazolyl, and lmldazo[2,1-b]thlazolyl groups are preferably mono- or dl-substituted (preferred mono-substituted) with methyl. If substituted, pyridyl groups are preferably mono- or di-substituted (preferred mono-substituted) with substituents independently selected from the group consisting of methyl, methoxy, chloro, bromo and trifluoromethyl. If substituted, pyrrolo[2,1-b]thiazolyl groups are preferably mono- or dl-substituted (preferred mono-substituted) with methyl. Benzothiazolyl and imidazofi ,2-a]pyridinyl groups are preferably unsubstltuted. Examples of R2 representing "heteroaryl" are 4- bromo-pyridine-2-yl, 5-bromo-pyridine-3-yl, 4-chloro-pyridine-2-yl, 5-chloro-pyridine-3-yl, 4-methyl-pyridine-2-yl, 5-methyl-pyridine-3-yl, 6-methyl-pyridine-2-yl, 2-methyl-pyridine-4-yl, 6-methoxy-pyridine-2-yl, 6-trifluoromethyl-pyridine-2-yl, 3,5-dimethyl-isoxazole-4-yl, 1 -methyl-1 H-inda2ole-3-yl, 2-methyl-b©nzofuran-4-yl, benzofuran-4-yl, benzo[d]isoxazole-3-yl, 2-methyl-benzoxazole-4-yl, benzo[d]isothiaZ9le-3-yl, imidazo[2,1-b]thiazole-5-yl, imidazo[2,1-b]thiazote-6^)||, and 6-meth^-lmidaflp[2,1-b]-thiazole-5-yl. In addition to the above-listed examplesilof R2 representing "hefteparyl", further examples are benzothiazol-7-yl, 3-methyl-benzofuran-4-yl, 6-methyi-pyrrolo[2,1 -b]thiazol-7-yl, and imidazo[1,2-a]pyridin-3-yl. Examples of "-NR®R2" groups are -NHg (preferred) and -N(CH3)2. The term "acyi" as used in the specification means an aryl-CO-, an alkyl-CO-, or a heteroaryl-CO- group, such as for example A-CO-, or R'-CO-, wherein A and R2 have the meaning given for formula (1). iii) A further embodiment of the invention relates to compounds of fomiula (I) according to embodiments i) or ii), wherein the configuration of the 3-aza-bicyclo[3.3.0]octane moiety is such that the -CH2-NH-C0-R2 substituent and the cyclopentane ring of the 3-aza-bicyclo[3.3.0]octane moiety are in trans relation (relative configuration (IS*, 2S*, 5R*)). iv) A further embodiment of the invention relates to compounds of formula (I) according to embodiments i) or ii), wherein the configuration of the 3-aza- bicycio[3.3.0]octane moiety is such that the -CHa-NH-CO-R2 substituent and the cyclopentane ring of the 3-aza-bicyclo[3.3.0]octane moiety are in cis relation (relative configuration (1R*, 2S*, 5S*)). ^ v) A further embodiment of the invention relates to compounds of formula (I) according to embodiments i) to iv), wherein the absc|lute configuration of the carbon center of the 3-aza-bicyclo[3.3.0]octane moiety to which the -CHa-NH-CO-R2 group is attached is (2S) as depicted In formula (IEI) vi) A further embodiment of the invention relates to compounds of formula (I) according to embodiments i), ii), iii) or v), wherein the absolute configuration is as depicted in formula (lea) vii) A further embodiment of the invention relates to 3-aza-bicyclo[3.3.0]octane derivatives according to any one of embodiments i) to vi), wherein R' represents hydrogen, or methyl; and R2 represents hydrogen. vlii) A further embodiment of the invention relates to 3-aza-blcyclo[3,3.0]octane derivatives according to any one of embodiments i) to vii), wherein A represents ix) A further embodiment of the invention relates to 3-aza-bicyclo[3.3.0]octane derivatives according to any one of embodiments i) to vlii), wherein A represents X) A further embodiment of the invention relates to 3-aza-bJcyclo[3.3.0]octane derivatives according to any one of embodiments 1) to ix), wherein R* represents methyl, or-NH2 (especially methyl). xi) A further embodiment of the invention relates to 3-aza-bicyclo[3.3.01octane derivatives according to any one of embodiments i) to vlii), wherein A represents xii) A further embodiment of the invention relates to 3-aza-bicyclo[3.3.0]octane derivatives according to any one of embodiments i) to xl), wherein D represents phenyl, which is unsubstltuted, mono-, dl-, or tri-substituted, wherein the substStuents are independently selected from the group consisting of (C1-4)alkyl, (C1-4)alkoxy, trjfinoromethyl, and halogen (especially the phenyl Is mono-, or dlsubstituted, wherein said substituents are preferably in position(s) 3, and/or 4). xiii) A further embodiment of the invention relates to 3-aza-bicyclo[3.3.0]octane derivatives according to any one of embodiments i) to xii), wherein R2 represents phenyl, which is unsubstituted, mono-, di-, or tri-substituted, wherein the substituents are independently selected from the group consisting of (Ci^)alkyl, (Cm)alkoxy, trifluoromethyl, trtfluoromethoxy, and halogein; 2,3-dihydro-ben?of^ranyl; benzo[1,3]dioxolyl; 2,3-dihydro-benzo[1,4]dioxinyl; i4H-benzo[1,3]dioxinyl; jOr an isoxazolyl, a pyridyl, an indazolyl, a benzofuranyl, a b^nzoxazolyl, a benziso^azc^yl, a benzoisothiazolyl, or an imidazo[2,1-b]thiazolyl group, wherein said groups are unsubstituted, mono-, di-, or tri-substituted, wherein the substituents are independently selected from the group consisting of (C1-4)alkyl, (C1-4)alkoxy, haksgen, anu trifluoromethyl. xiv) A further embodiment of the invention relates to 3-aza-bicyck)l3.3.0]octane derivatives according to any one of embodiments 0 to xiii), wherein R2 represents phenyl, which is unsubstituted, mono-, di-, or tri-substituted, wherein the substituents are independently selected from the group consisting of (C1-4)alkyl, (Ciwi)alkoxy, trifluoromethyl, trifluoromethoxy, and halogen; 2,3-dihydro-benzofuranyl; benzo[1,3]dioxolyl; 2,3-dihydro-benzo[1,4]dioxlnyl; 4H-benzoI1,3]dioxinyl; or an isoxazolyl, a pyridyl, an indazolyl, a benzofuranyl, a benzoxazolyl, a benzisoxazolyl, or a benzoisothiazolyl group, wherein said groups are unsubstituted, mono-, di-, or tri-substituted, wherein the substituents are independently selected from the group consisting of (Ci^)alkyl, (C1-4)alkoxy, halogen, and trifluoromethyl. XV) A further embodiment of the invention relates to 3-aza-bteyclo[3.3.0]octane derivatives according to any one of embodiments 1) to xiii), wherein R2 represents an isoxazolyl, a pyridyl, an indazolyl, a benzofuranyl, a benzoxazolyl, a benzisoxazolyl, a benzoisothiazolyl, or an imidazo[2,1-b]thiazolyl group, wherein sakl groups are unsubstituted, mono-, di-, or tri-substituted, wherein the substituents are independently selected from the group consisting of i(CM)alkyl, (C1-4)alkoxyi halogen, and trifluoromethyl. xvi) A further embodiment of the invention relates to 3-aza-bicyclo[3.3.0]octane derivatives according to any one of embodiments i) to xiii), wherein R2 represents phenyl, which is unsubstituted, mono-, di-, or tri-substituted, wherein the substituents are independently selected from the group consisting of (C1-4)alkyl, (C1-4)alkoxy, trifluoromethyl, trifluoromethoxy, and halogen; or a 2,3-dihydro-benzofuranyl-, a benzo[1,3]dioxolyl-, a 2,3-dihydro-benzo[1,4]dioxinyl-, or a 4H-benzo[1,3]dioxinyl-gruup (especially a 2,3-dihydro-benzo[1,4]dioxinyl- group), said groups being unsubstituted. xvii) A further embodiment of ttie invention relates to 3-aza-bicyclo[3.3.0]octane derivatives according to any one of embodiments i) to xiii) or xv), wherein R2 represents or pyridyl, which is mono-substituted, wherein the substituent is selected from the group consisting of methyl, methoxy, chloro, bromo and trifluoromethyl. xviii) A further embodiment of the invention relates to 3-aza-bicyclo[3.3.0]octane derivatives according to any one of embodiments i) to xiv), wherein R2 represents xix) A further embodiment of the invention relates to 3-aza-bicyclo[3.3.0]octane derivatives according to any one of embodiments i) to xiii), xv), or xvii), wherein R2 represents XX) A further embodhTient of the invention relates to 3-aza-bicyclo[3.3.0Joctane derivatives according to any one of embodiments I) to xiii), xv), xvii), or xix), wherein R2 represents xxi) A further embodiment of the invention relates to 3-aza-bicyclo[3.3.0]octane derivatives according to any one of embodiments i) to vi), ix), x) or xii), wherein R2 and R2 both represent fluorine. xxii) A further embodiment of the invention relates to 3-aza-bicyclo[3.3.0]octane derivatives according to any one of embodiments i) to xli), wherein R2 represents phenyl, which is unsubstituted, mono-, di-, or tri-substituted, wherein the substituents are independently selected from the group consisting of (C1-4)alky), (CM)alkoxy, trifluoromethyl, trifluoromethoxy, and halog^i; 2,3-dihydro-ben2|ofuranyl; ben20[1,3]dioxolyl; 2,3-dihydro-ben2o[1,4]dioxinyl; '4H-benzol1,31dioxinyl; or an isoxazolyl, a pyridyl, an indazolyl, a benzofuranyl, a benzoxazolyl, a benzisoxazolyl, a benzothiazolyl, a benzoisothiazoiyl, a pyrrolo[2,1-b]thiazolyl, an imidazo[1,2-ajpyridinyl, or an imidazo[2,1-b]thiazoiyl group, v^^ereln said groups are unsubstituted, mono-, di-, or trl-substituted, wherein the substituents are independently selected from the group consisting of (C1-4)alkyl, (C1-4)alkoxy, halogen, and trifluoromethyl. xxiii) A further embodiment of the invention relates to 3-aza-bicyclo[3.3.0]octane derivatives according to any one of embodiments i) to xii), xxi) or xxii), wherein R2 represents or pyridyl, which is mono-substituted, wherein the substituent is selected from the group consisting of methyl, methoxy, chloro, bromo and trifluoromethyl. Kxiv) A further embodiment of the invention relates to 3-aza-bicyclo[3.3.0]CKJtane derivatives according to embodiment xxi), wherein R2 represents a group selected from the group consisting of 2,3-dihydro-benzofuran-4-yl, 2,3-dihydro-benzofl ,41dioxin-5-yl, 1-methyl-1H-indazole-3-yl, benzothla2ol-7-yl, 2-methyl-benzofuran-4-yl, 3-methyl-benzofuran-4-yl, 6-methyl-pyrrolo[2,1-b]thiazol-7-yl, imidazo[1,2-a]pyridln-3-yl, and 6-methyl-imidazo[2,1-b]-thiazole-5-yl. xxv) A further embodiment of the invention relates to 3-aza-bicyclo[3.3.0]octane derivatives of formula (I) according to embodiments i) to vi) wherein at least one, preferably all of the following characteristics are present: • R2 represents hydrogen, or methyl; • R2 represents hydrogen; i • R2 represents phenyl, which is unsubstitUted, mono-, dr di-substituted, wherein the substituents are independenljly selected fi'om thp' group consisting of (Ci^)alkyl, (C1-4)alkoxy, trifluorbmethyl, trifluoromethoxy, and halogen; 2,3-dihydro-benzo[1,4]dioxinyl; an isoxazolyl, an indazolyl, a benzofuranyl, a benzoxazolyl, a benzisoxazolyl, a benzoisothlazolyl, or an imidazo[2,1-b]thiazolyl group, wherein said groups are unsubstituted, or mono-substituted, wherein the substituent is selected from the group consisting of (C1-4)ail]thiazole-5-carboxylic acid-(1 S,2S,5R)-{7-methyl-3-[2-methyl- 5-(3-trifluoromethyl-phenyl)-thiazole-4-carbonyl]-3-aza-bicyclo[3.3.01oct-2-ylmethyl}- amide; 6-Methyl-imidazo[2,1-fa]thiazole-5-carboxylic acid-(1S,2S,5R)-{3-(5-(3-fluoro-phenyl)- 2-methyl-thiazole-4-carbonyl]-3-aza-bicyclo[3.3.0]oct-2-ylmethyl}-amide; 6-Methyl-imidazo[2,1 -d]thiazole-5-carboxylic acid-(1 S,2S,5R)-{3-[5-(3-fluoro-phenyl)- 2-methyl-thiazole-4-carbonyl]-7-methyl-3-aza-bicyclo[i3.3.0]oct-2-ylmethyl}-amide; 6-Methyl-imidazo[2,1 -t>]thiazole-5-carboxylic acid-(1 Si2S,5R)-[7-methyl-3-(2-mettiyl- 5-p-tolyl-thiazole-4-carbonyl)-3-aza-bicyclo[3.3.0]oct-2-ylmethyr|-amide; 6-Methyl-imidazo[2,1 -d]thlazole-5-carboxylic acid-(1 S,2S,5R)-[3-(2-methyl-5-R-tolyl- thiazole-4-carbonyl)-3-aza-bicyclo[3.3.0]oct-2-ylmethyl]-amide; 6-Methyl-imidazo[2,1 -b]thiazole-5-carboxylic acid-(1 S,2S,5R)-{3-[5-(3-chloro-phenyl)- 2-methyl-thiazole-4-carbonyl]-3-aza-bicyclo[3.3.0]oct-2-ylmethyl}-amide; 6-Methyl-imidazo[2,1 -dlthiazole-S-carboxylic acid-(1 S,2S,5R)-{3-l5-(3-chloro-phenyl)- 2-methyl-thiazole-4-carbonyl]-7-methyl-3-aza-bicycloI3.3.0]oct-2-ylmethyl}-amide; 6-Methyl-imidazo[2,1 -b]thlazole-5-carboxylic acid-(1 S,2S,5R)-{3-[5-(4-methoxy- phenyl)-2-methyl-thiazole-4-carbonyl]-3-aza-bicyclo{d.3.0Joct-2-ylmethyl}-amide; 6-Methyl-imidazo[2,1 -b]thiazole-5-carboxylic acid-(1 S,2S,5R)-{3-[5-(4-methoxy- phenyl)-2-methyl-thlazole-4-carbonyll-7-methyl-3-a2a-bicyclo[3.3.0]oct-2-ylmethyl}- amide; 6-lvi3thyl-imldazo[2,1 -b]thiazole-5-carboxylic acid-(1 S,2S,5R)-{3-[5-(4-ethyl-phenyl)- 2-methyl-thiazole-4-carbonyl]-7-methyl-3-aza-bicycloI3.3,0]oct-2-ylmethyl}-amide; 6-Methyl-imidazoI2,1 -/)]thiazole-5-carboxylic acid-(1 S,2S,5R)-{7-methyl-3-[2-methyl- 5-(4-trifluoromethyl-phenyl)-thiazol©-4-carbonyl]-3-aza-bicyclo[3,3,0]oct-2-ylmrthyl}- amide; 6-Methyl-imidazoI2,1 -/b]thiazole-5-carboxylic acid-(1 S,2S,5R)-{3-[5-(4-fluoro-ph©nyl)- 2-methyl-thiazole-4-carbonyl]-7-methyl-3-aza-bicyclo[3.3.0]oct-2-ylmethyl}-amlde; ■1 ! >[ ' ■ 6-Methyl-imidazo[2,1 -b]-thiazole-5-carboxylic acid-(1 S,2S,5R)-{7-m©thyl-3-[2-methyl- 5-phenyl-thiazole-4-carbonyl]-3-aza-bicyclo[3.3.0]oct-2-ylmethyl}-amide; 6-Methyl-imidazo[2,1 -dlthiazole-S-carboxylic acid-(1 S,2S,5R)-{3-[57(3,4-dimethyl- phenyl)-2-methyl-thiazole-4-carbonyl]-7-methyl-3-aza-bicyclo[3.3.0]oct-2-ylmethyl}- amide; 6-Methyl-imidazo[2,1-d]thiazole-5-carboxylic acid-(1 S,2S,5R)-{3-[5-(3,4-dinnethyl- phenyl)-2-methyl-thia2Ole-4-carbonyl]-3-aza-bicyclof3.3.0]oct-2-ylmethyl}-amlde; 6-Methyl-imidazo[2,1-fa]thiazole-5-carboxylic acid-(1S,2S,5R)-{3-[5-(3,4-difluoro- phenyl)-2-methyl-thiazole-4-carbonyl]-7-methyl-3-aza-bicyc(o[3.3.0]oct-2-ylmethyl}- amide; 6-Methyi-imidazo[2,1 -6]tliiazole-5-carboxylic acid-(1 S,2S,5R)-{3-t5-(3,4-difluoro- plienyl)-2-methyl-tliiazole-4-carbonyl]-3-aza-bicyclo[3.3.0]oct-2-ylmethyl}-amide; 6-l\/lethyl-imidazo[2,1-f)]thiazole-5-carboxylic acid-(1S,2S,5R)-[3-(2-amino-5-phenyl- tliiazole-4-carbonyl)-7-methyl-3-aza-blcyclo[3.3.0]oct-2-ylmethyO-amide; 6-Methyl-imidazo[2,1'/)]thiazole-5-carboxylic acid-(1 S,2S,5R)-[3-(biphenyl-2- carbonyl)-7-methyl-3-aza-bicyclo[3.3.0]oct-2-ylmethyQ-amide; 6-Methyl-imidazo[2,1-b]thlazole-5-carboxylic acid-(1S,2S,5R)-r7-methyl-3-(3'-methyl- biplienyl-2-carbonyl)-3-aza-bicyclo[3.3.0]oct-2-yimethyl]-amlde; 6-Metliyl-imidazo[2,1 -/j]-thiazole-5-carboxylic acid-(1 S,2S,5R)-[7-metliyl-3-(4'-metliyl- biphenyl-2-carbonyl)-3-aza-bicyclo[3.3.0]oct-2-ylmethyll-amide; 6-Metliyl-imidazo[2,1 -b]-tlilazole-5-carboxylic acld-(1 S,2S,5R)-|7-metliyl-3-(4'-fluoro- biphenyl-2-carbonyl)-3-aza-bicyclo[3.3.0]oct-2-ylmethyO-amlde; 6-Methyl-imida2o[2,1 -b]-thlazole-5-carboxylic acid-(1 S,2S,5R)-[7-methyl-3-(3'- metlioxy-biplienyl-2-carbonyl)-3-aza-bicyclo[3.3.0]oct-2-ylmethyi]-amide; 6-Methyl-imida20[2,1 -bJ-thiazole-S-carboxyllc acld-(1 S,2S,5R)-[7-methyl-3-(4'-chloro- biphenyl-2-carbonyl)-3-aza-bicyclo[3.3.0]oct-2-ylmethyO-amide; 6-Metliyl-imidazo[2,1 -b]thiazole-5-carboxylic acid-(1 S,2S,5R)-[3-(biphenyl-2- carbonyl)-3-aza-bicyclo[3.3.0]oct-2-ylmetliyl]-amide; , 6-Methyl-imidazo[2,1 -ti]-thiazole-5-carboxylic acid-(1 S,2S,5R)-[3-(4'-fluoro-biplienyl- 2-carbonyl)-3-aza-bicyclol3.3.0Joct-2-ylmethyl]-amide; 6-l\^ethyl-imidazo[2,1 -b]-thiazole-5-carboxylic acid-(1 S,2S,5R)-[3-(3'-methyl-biphenyl- 2-carbonyl)-3-aza-bicyclo[3.3.0]oct-2-ylmethyl]-amide; 6-Metliyl-imida2o[2,1 -6]-thiazole-5-carboxylic acid-(1 S,2S,5R)-[3-(3"-methoxy- biplienyl-2-carbonyl)-3-aza-bicyclo[3.3.0]oct-2-ylmethyl]-amide; 6-l\/letliyl-imida2o[2,1 -b]-tliiazole-5-carboxylic acid-(1 S,2S,5R)-I3-(2-methyl-5-phenyl- tliiazole-4-carbonyl)-3-aza-bicyclo[3.3.0]oct-2-ylmetliyl]-amld©; 6-Methyl-imidazo[2,1 -6]thiazole-5-carboxylic acid-(1 S,2S,5R)-{3-[5-(4-fluoro-phenyl)- 2-methyl-thiazole-4-carbonyl]-3-aza-bicyclo[3.3.0]oct-2:ylmethyl}-amide; ^ 6-Methyl-imidazo[2,1 -d]thiazole-5-carboxylic acid-(1 S,2S,5R)-{3-[5-(4-ethyl-phenyl)- 2-methyl-thiazole-4-carbonyl]-3-aza-bicyclo[3.3.0]oct-2-ylmethyl}-amlde; 6-Methyl-imidazo[2,1 -jb]thiazole-5-carboxylic acid-(1 S,2S,5R)-{3-I5-(4-chloro-phenyl)- 2-methyl-thiazole-4-carbonyl]-3-aza-blcyclo[3.3.0]oct-2-ylmethyl}-amide; 6-Methyl-imidazo[2,1 -Z)]thia2ole-5-carboxylic acid-(1 S,2S,5R)-{3-[2-methyl-5-(4- triflijoromethyl-phenyl)-thiazole-4-carbonyl]-3-aza-bicyclo[3.3.0]oct-2-ylmethyl}- amide; . 6-Methyl-imidazo[2,1 -6]thiazole-5-carboxylic acid-(1 S,2S,5R)-{3-[2-amino-5-(3- methyl-phenyl)-thiazole-4-carbonyl]-3-aza-bicyclo[3.3.0]oct-2-ylmethyl}-amide; 6-Methyl-imidazo[2,1 -b]thiazole-5-carboxylic acid-(1 S,2S,5R)-{3-[2-amino-5-(3-fluoro- phenyl)-thiazole-4-carbonyl]-3-aza-blcyclo[3.3.0]oct-2-ylmethyl}-amlde; 6-Methyl-imidazo[2,1 -b]thiazole-5-carboxylic acid-(1 S,2S,5R)-l3-(2-amlnd-5-phenyl- thiazole-4-carbonyl)-3-aza-bicyclo[3.3.0]oct-2-ylmethyl]-amid©; 6-Methyl-imidazo[2,1 -b]thiazole-5-carboxylic acid-(1 S,2S,5R)-{7-methyl-3-[2-amino- 5-(3-methyl-phenyl)-thiazole-4-carbonyl]-3-aza-bicyclo[3.3.0]oct-2-ylmethyl}-amide; 6-Methyl-imidazo[2,1 -b]thiazole-5-carboxylic acid-(1 S,2S,5R)-{7-methyl-3-[2-amino- 5-(4-fluoro-phenyl)-thiazole-4-carbonyl]-3-aza-bicyclol3.3.01oct-2-ylmethyl}-amide; 6-Methyl-imidazo[2,1 -ib]thiazole-5-carboxylic acld-(1 S,2S,5R)-{7-methyl-3-[2-amlno- 5-(3-fluoro-phenyl)-thia2ole-4-carbonyl]-3-aza-bicyclo[3.3.01oct-2-ylmethyl}-amWe; and lmidazo[2,1 -d]thiazole-6-carboxylic acid-(1 S,2S,5R)-I3-(2-methyl-5-m-tolyl-ihiazole-4- carbonyl)-3-aza-bicyclo[3.3.0]oct-2-ylmethyl]-anriide; wherein it is well understood that In case the above-listed compounds contain a (1S,2S,5R)-7-methyl-3-aza-blcycloI3.3.0]oct-2-ylmethyl moiety, such moiety may be in absolute (1 S,2S,5R,7R)- or in absolute (1 S,2S,5R,7S)-configuration. xxix) In addition to the compounds listed in embodiments xxvii) and xxviii), further examples of compounds of fonnula (I) according to embodbnent i) are selected from the group consisting of: 2-Methyl-benzofuran-4-carboxylicacid-(1S,2S,5R)-[7,7-difluoro-3-(2-methyl-5-m-tolyl- thiai:ole-4-carbonyl)-3-aza-bicycloI3.3.0]oct-3-ylmethyl]-amlde; 3-Methyl-benzofuran-4-carboxyllcacld-(1S,2S,5R)-I7,7-dlfluoro-3-(2-methyl-5-m-tolyl- thiazole-4-carbonyl)-3-aza-blcycloI3.3.0]oct-3-ylmethyl]-amlde; 2,3-Dihydro-benzofuran-4-cait)oxylicacid-(1S,2S,5R)-[7.7-dlfluoro-3-(2-methyl-5-m- tolyl-thiazole-4-carbonyl)-3-aza-bicyclo[3.3.0]oct-2-ylmethyf|-amide; 2,3-Dihydro-benzo[1,4]dioxine-5-carboxylic acicl-(1S,2S,5R)-[7,7-difluoro-3-(2-methyl- 5-m-tolyl-thiazole-4-carbonyl)-3-aza-bicyclo[3.3.0]oct-2-ylmethyl]-amide; Benzothiazole-7-carboxylic acid-(1 S,2S,5R)-[7,7-difluqro-3-(2-methyl-5-m-tolyl- thiazole-4-carbonyl)-3-aza-bicycloI3.3.0]oct-2-ylmethyU-amide; t' 6-Methyl-pyrrolo[2,1 -b]thiazole-7-carboxylic acid-(1 S,2S,5R)-[7,7-difluoro-3-(2- methyl-5-m-tolyl-thiazole-4-cartonyl)-3-aza-blcyclo[3.3.0]oct-2-ylmethyl]-amide; lmidazo[1,2-a]pyridine-3-carboxylic acid-(1 S,2S,5R)-[7,7-dtfluoro-3-(2-methyl-5-m- tolyl-thiazole-4-carbonyl)-3-aza-bicyclo[3.3.0]oct-2-ylmethyl]-amlde; 1 -Methyl-indazole-3-carboxylic acid-(1 S,2S,5R)-[7,7-difluoro-3-(2-methyl-5-m-tolyl- thiazole-4-carbonyl)-3-a2a-bicyclo[3.3.0]oct-2-ylmethyl]-am»de,and 6-Methyl-imidazo[2,1-b]-thiazole-5-carboxylic acid-(1 S,2S,5R)-[7,7-dlfludro-3-(2- methyl-5-m-tolyl-thiazole-4-carbonyl)-3-aza-bicyclo[3.3.0]oct-2-ylmethyl]-amide. The compounds of formula (I) and their pharmaceutically acceptable salts can be used as medicaments, e.g. in the form of pharmaceutical compositions for enteral or parenteral administration. The production of the pharmaceutical compositions can be effected In a manner which will be familiar to any person skilled in the art (see for example Remington, The Science and Practice of Pharmacy, 21st Edition (2005), Part 5, "Pharmaceutical Manufacturing" [published by Lippincott Williams & Wilkins]) by bringing the described compounds of formula (I) or their pharmaceutically acceptable salts, optionally in combination with other therapeutically valuable substances, into a galenical administration form together with suitable, non-toxic, inert, therapeutically compatible solid or liquid carrier materials and, if desired, usual pharmaceutical adjuvants. i' The present invention also relates to a method for the prevention or treatment of a disease or disorder mentioned herein comprising administering to a subject a pharmaceutically active amount of a compound of fomiuia (I). The compounds according to formula (I) are suitable and/or may be used for the preparation of a medicament for the prevention or treatment of diseases selected from the group consisting of dysthymic disorders including major depression and cyclothymia, affective neurosis, all types of manic depressive disorders, delirium, psychotic disorders, schizophrenia, catatonic schizophrenia, delusional paranoia, adjustment disorders and all clusters of personality disorders; schizoaffective disorders; anxiety disorders including generalized anxiety, obsessive compulsive disorder, posttraumatic stress disorder, panic attacks, all types of phobic anxiety and avoidance; separation anxiety; all psychoactive substance use, abuse, seeking and I reinstatement; all types of psychological or physical addictions, dissociative disorders including multiple personality syndromes and psychogenic amnesias; sexual and reproductive dysfunction; psychosexual dysfunction and addiction; tolerance to narcotics or withdrawal from narcotics; increased anaesthetic risk, anaesthetic responsiveness; hypothalamic-adrenal dysfunctioris; disturbed biologicsfl and circadian rhythms; sleep disturbances associated with diseases such as neurological disorders including neuropathic pain and restless leg syndrome; sleep apnea; narcolepsy; chronic fatigue syndrome; insomnias related to psychiatric disorders; all types of idiopathic insomnias and parasomnias; sleep-wake schedule disorders including jet-lag; all dementias and cognitive dysfunctions In the healthy population and in psychiatric and neurological disorders; mental dysfunctions of aging; ail types of amnesia; severe mental retardation; dyskinesias and muscular diseases; muscle spasticity, tremors, movement disorders; spontaneous and medication-induced dyskinesias; neurodegenerative disorders including Huntington's, Creutzfekl-Jacob's, Alzheimer's diseases and Tourette syndrome; Amyotrophic lateral sclerosis; Parkinson's disease; Cushlng's syndrome; traumatk; iesbns; spinal cord trauma; head trauma; perinatal hypoxia; hearing loss; tinnitus; demyelinating diseases; spinal and cranial nerve diseases; ocular damage; retinopathy; epilepsy; seizure disorders; absence seizures, complex partial and generalized seizures; Lennox-Gastaut syndrome; migraine and headache; pain disorders; anaesthesia and analgesia; enhanced or exaggerated sensitivity to pain such as hyperalgesia, causalgia, and allodynia; acute pain; burn pain; atypical facial pain; neuropathic pain; back pain; complex regional pain syndrome I and II; arthritic pain; sports injury pain; dental pain; pain related to infection e.g. by HIV; post-chemotheijapy pain; post-stroke pain; post¬operative pain; neuralgia; osteoarthritis; conditions associated with visceral^pf in such as irritable bowel syndrome; eating disorders; diabetes; toxic and dysmetabolic disorders including cerebral anoxia, diabetic neuropathies and alcoholism; appetite, taste, eating, or drinking disorders; somatoform disorders including hypochondriasis; vomiting/nausea; emesis; gastric dyskinesia; gastric ulcers; Kallman's syndrome (anosmia); impaired glucose tolerance; intestinal motility dyskinesias; hypothalamic diseases; hypophysis diseases; hyperthermia syndromes, pyrexia, febrile seizures, idiupathic growth deficiency; dwarfism; gigantism; acromegaly; basophil adenoma; prolactinoma; hyperprolactinemia; brain tumors, adenomas; benign prostatic hypertrophy, prostate cancer; endometrial, breast, colon cancer; all types of testicular dysfunctions, fertility control; reproductive hormone abnormalities; hot flashes; hypothalamic hypogonadism, functional or psychogenic amenorrhea; urinary bladder incontinence; asthma; allergies; all types of dermatitis, acne and cysts, sebaceous gland dysfunctions; cardiovascular disorders; iieart and lung diseases, acute and congestive heart failure; hypotension; hypertension; dysiipidemias, hyperlipidemias, insulin resistance; urinary retention; osteoporosis;| angina pectoris; myocardial infarction; arrhythmias, coronary diseases, left ventricular hypertrophy; ischemic or haemorrhagic stroke; all types of cerebrovascular di^rders includirig subaraphnoid haemorrhage, ischemic and hemorrhagic stroke aiid; vascular dementiai ^hronlc renal failure and other renal diseases; gout; kidney cancer; urinary incontinence; and other diseases related to general orexin system dysfunctions. Compounds of formula (I) are particularly suitable and/or may be used for the preparation of a medicament for the treatment of diseases or disorders selected from the group consisting of all types of sleep disorders, of stress^related syndromes, of psychoactive substance use,, abuse, seeking and reinstatdment, of cognitive dysfunctions in the healthy population and in psychiatric and neurok>gk; disorders', of eating or drinking disorders. 4' Eating disoiflers may be defined as comprising metabolic dysfunctksn; dysregulated appetite control; compulsive obesities; emeto-bulimia or anorexia nervosa. Pathologically modified food intake may result from disturbed appetite (attractton or aversion for food); altered energy balance (Intake vs. expenditure); disturbed perception of food quality (high fat or carbohydrates, high palatability); disturbed food availability (unrestricted diet or deprivation) or dist'upted water balance. Drinking disorders include polydipsias in psychiatric disorders and all other types of excessive fluid Intake. Sleep disorders include all types of parasomnias, insomnias, narcolepsy and other disorders of excessive sleepiness, sleei(}-related dystonias; restless leg syndrome; sleep apneas; jet-lag syndrome; shift-work syndrome, delayed or advanced sleep phase syndrome or insomnias related to psychiatric disorders. Insomnias are defined as comprising sleep disorders associated vi^ith aging; intermittent treatment of chronic insomnia; situational transient insomnia (new environment, noise) or short-term insomnia due to stress; grief; pain or illness. Insomnia also include stress-related syndromes including post-traumatic stress disorders as well as other types and subtypes of anxiety disorders such as generalized anxiety, obsessive compulsive disorder, panic attacks and all types of phobic anxiety and avoidance. Psychoactive substance use, abuse, seeking and reinstatement are defined as all types of psychological or physical addictions and their related tolerance and dependence components. Cognitive dysfunctions include deiicits in ail types of attention, learning and memory functions occurring transiently or chronically in the normal, healthy, young, adult or aging population, and also occurring transiently or chronically in psychiatric, neurologic, cardiovascular and immune disorders. In a further preferred embodiment of the invention compounds of formula (I) are particularly suitable for the treatment of diseases or disorders selected from the group consisting of sleep disorders that ccMTiprises all types of insonnias, narcolepsy and other disorders of excessive sleepiness, sleep*related dystonias, restless leg syndrome, sleep apneas, jet-lag syndrome, shift-^work syndrome, delfayed or advanced sleep phase syndrome or insomniap^ related to psychiatric disorders. In another preferred embodiment of the invention compounds of formula (I) are particularly suitable and/or may be used for the preparation of a medicament for the treatment of diseases or disorders selected from the group consisting of cognitive dysfunctions that comprise deficits in all types of attention, learning and memory functions occurring transiently or chronically in the normal, healthy, young, adult or aging population, and also occurring transiently or chronically in psychiatric, neurologic, cardiovascular and immune disorders. In another preferred embodiment of the invention compounds of formula (I) are particularly suitable and/or may be used for the preparation of a medicament for the treatment of diseases or disorders selected from the group consisting of eating disorders that comprise metabolic dysfunction; dysregulated appetite control; compulsive obesities; emeto-bulimia or anorexia nervosa. In another preferred embodiment of the invention compounds of formula (I) are particularly suitable and/or may be used for the preparation of a medicament for the treatment of diseases or disorders selected from the group consisting of psychoactive substance use, abuse, seeking and'reinstatement that comprjse all types of psychological or physical addictions and their related tolerapce and dependence components. Preparation of compounds of formula (I): A further aspect of the invention is a process for the preparation of compounds of formula (I). Compounds according to formula (I) of the present invention can be prepared according to the sequence of reactions outlined in the schemes below wherein A, D, R\ R2 R2 R*. R2 R2 and R2 are asj defined for fonnula (I). Other abbreviations used are defined in the experimental section. In some instances the generic groups A, D, R\ R2 R2 R*, R2 R2 and R2 JTiight be Incompatible with the assembly illustrated in the schemes below and so vyill require the use of prc^teptlng groups (PG). The use of protecting groups is well knj^wn in the art (see forje^cample "Protective Groups in Organic Synthesis", T.W. Greene, P.G.M. Wut's.iWiley-Interscience, 1999). For the purposes of this discussion, it will be assumed that such protecting groups as are necessary are in place., Ift general, all chemical transformations can be performed according to well-known standard methodologies as described in the literature or as described in the procedures below. The compounds obtained may also be converted into pharmaceutically acceptable salts thereof in a manner known per se. 3-Aza-bicyclo[3.3.0]octane derivatives of fonnula (I) are prepared from protected 3-aza-bicyclo[3.3.0]octane derivatives of structure (1) or structure (2) as shown in scheme 1. Compounds of structure (1) are transfomned into compounds of structure (2) by replacement of the benzyl protecting group with a Boc group via hydrogenolysis and subsequent reactton with BoczO. The alcohol (2) is oxidized, for example under Swern conditions, to give the corresponding aldehyde (3). Reductive amination with benzylamlne in the presence of a reducing agent such as NaBH(0Ac)3 followed by the removal of the benzyl group by hydrogenolysis furnishes the primary amine (4). The use of commercially available, enantiomerically pure 1-phenyl-ethylamine instead of benzylamine in the first step of the above sequence, separation of the so fomned diastereoi^omers by means known to the person skilled in the art, followed by removal pf the 1-phenyl-ethyl group by hydrogenolysis as described leads to the corresponding enantiomerically pure amines (4). Acylatlon of amine (4) with carboxylic acid derivatives R2-COdH in the presence of a coupling reagent such as TBTU results in the formation of amides (5) which, after removal of the Boc-group under acidic conditions, are acylated with carboxylic acid derivatives A-COOH using amide coupling reagents such as TBTU to give compounds of fomnula (I). Scheme 1: Synthesis of compounds of formula (I), wherein R2 and R2 are hydrogen Alternatively, 3-a2a-bicyclo[3.3.0]octane derivatives of fomiula (I) are prepared from amines of structure (4) as shown in scheme 2. Amines of structure (4) are protected by reaction with ethyl trifluoroacetate in aprotic solvents such as THF to give trifluoroacetamide derivatives (6). Removal of the Boc protecting group under acidic conditions such as TFA in DCM yields amine derivatives (7), which are then coupled with a carboxylic acid derivative A-COOIH in the presence of a coupling reagent such as TBTU to yield amide derivatives (8). Scheme 2: Synthesis of compounds of formula (I) After deprotection of the trifluoroacetamide under basic conditions such as KgCOa in IVIeOH/water mixtures, amine derivatives (9) are obtained which are coupled with carboxylic acid derivatives R2-COOH in tlie presence of a coupling reagent sucli as TBTU to compounds of formula (I). 3-Aza-blcyclo[3.3.0]octane derivatives of structure (1), wherein R' and R2 represent hydrogen are prepared as described in the literature (WO03/062265; Jao E. et al Tetrahedron Letters, 2003, 44, 5033-5035). Alternatively, 3-aza-bicyclo[3.3.0]octane ' derivatives of structure (1) are prepared from known compounds of structure (10) in scheme 3 (Bergmeier S.C. et al Tetrahedror) 1999, 55, 8025-8038) by protecting the amine with a benzyl group using for example benzylbromide as alkylating reagent and reduction of the carboxylic acid to the alcohol using methods well known in the art such as LAH in THF, Alternatively, compounds of,struQture (10) can be protected with a Boc group and reduced to provide compounds of structure (2) Scheme 3: Synthesis of compounds of structure (1), wherein R' and R2 represent hydrogen Compounds of structure (1), wherein R' represents methyl and R2 represents hydrogen, are prepared from the known ketene cycloadduct (11) (Jao E. et al Tetrahedron Letters, 2003, 44, 5033-5035) as shown In scheme 5. Hydrogenation of the double bond gives the intermediate (12), which is then transformed to the desired alcohol of structure (1), wherein R2 represents methyl and R2 represents hydrogen, using excess of LAH in aprotic solvents such as THF under reflux conditions. Scheme 5: Synthesis of compounds of structure (1), wherein R2 represents methyl and R* represents hydrogen Alternatively, compounds of structure (1) are prepared from the known ketone of structure (13) (WO03/062265) as shown in scheme 6. Transfomiation of the ketone using well known alkyl Wittig reagents and subsequent reduction of the so formed double bond gives the Intermediate (12), wherein R2 represents hydrogen. Alternatively, reaction of the ketone with alkyl-zinc reagents as described in (Reetz M.T. et al Angewandte Chemie 1980, 92(11), 931 -933; J. Org. Chem. 1983. 48, 254-255; Chemische Berichte 1985, 118(3), 1050-1057) furnishes compounds of structure (12) wherein R' and R2 represent (Ci^)alkyl. Compounds of stmcture (12) can be transformed into compounds of structure (1) as described before. Scheme fi: Synthesis of compounds of structure (1) 3-Aza-bicyclo[3.3.0]octane derivatives of fomiula (I), wherein R2 and R2 both represent fluorine are prepared as described in the literature (WO03/062265) or according to scheme 7. Scheme 7: Synthesis of compounds of structure (I) Fluorination of ketone (13) by reaction with DAST \n a aprotic solvent such as DCM afforded intemiediate (14). Reduction with lithium aluminium hydride in a aprotic solvent such as THF furnished the desired alcohol (15). MItsunobu reaction with phthalimide in the presence of DEAD and triphenylphosphine in a aprotic solvent such as THF yielded the intemiediate (16). Cleavage of the benzyl group by transfert hydrogenation with ammonium fomiate and Pd-C 10% in MeOH followed by coupling with a carboxyllc acid A-COOH in the presence of a coupling reagent such as TBTU afforded intemiediate (17). Cleavage of the phthalimide by reaction with hydrazine monohydrate in EtOH followed by coupling with a carboxyllc add R2-COOH In the presence of a coupling reagent such as TBTU afforded the desired compounds of fomnula (I). Preparation of carboxyllc adds A-COOH Acids of the formula A-COOH are commercially available or synthesized according to methods described below. Carboxyllc acid derivatives A-COOH wherein A repnpsents a thlazole-4-yl derivative are commercially available or can be synthesised acoprding to scheme 7. Scheme 7: Synthesis of carboxyiic acids A-COOH wherein A represents a thiazole-4-yl derivative By reaction of methyl dichloroacetate (14) with an aldehyde of the formula D-CHO In the presence of a base such as KOfBu in an aprotic polar solvent such as THF at RT 3'-chloro-2-oxo-proplonic acid ester derivatives (15) are obtained. Compounds of structure (15) can be transformed by reaction with commercially available thioamides or thioureas R2-C(S)-NH2 at RT in solvents such: as MeCN to provide thlazol-4-carboxylic acid ester derivatives (16). Saponification of the ester function using methods known in the art such as treatment with a,base such as NaOH in a solvent such as MeOH provides the corresponding thiazol-4-carboxylic add derivatives (17). Aldehydes of formula D-CHO are commercially available or well known In the art. Carboxylic acid derivatives A-COOH wiierein A represents a thiazole-S-yl derivative are commercially available or synthesised according to scheme 8. Scheme 8: Synthesis of carboxylic acids A-COOH wHerein A represents a thiazoie-S-yl derivative By refluxing a commercially available 3-oxo-propionic acid ester derivative (| 8) with SO2CI2 in a solvent such as CHCia the corresponding 2-chloro-3-oxo-propionic acid ester derivatives (19) can be obtained. Compounds of structure (19) can be transformed by reaction with commercially available thioamides or thioureas R2-C(S)-NH2 at reflux temperature In solvents such as THF in presence of a base such as NaHCOs to the corresponding thiazol-5-caftbxylic acid ester derivatives (20). Saponification of the ester function using methods known in the art such as treatment with a base such as KOIH in a solvent such as EtOH provides the corresponding thiazol-5-carboxylic acid derivatives (21). Carboxylic acid derivatives A-COOH wherein A represents a oxazole-4-yf derivative which are commercially available or synthesised according to scheme 9. By reaction of a commercially available 3-oxo-propionic acid ester derivative (22) with an aq. solution sodium nitrite in presence of an acid such as glacial acetic acid the corresponding oxime derivative (23) can be obtained. The 2-acetamido-3-oxo-propionic acid ester derivative (24) can be synthesized from compounds of structure (24) using a carboxylic acid anhydride such as acetic acid anhydride in presence of an acid such as glacial acetic acid and catalytic amounts of metal chlorides such as mercury chloride and zinc powder. Cyclization to fhe corresponding corresponding oxazole-4-carboxylic acid ester derivative (25) cah be achieved under dehydrating conditions such as thionyl chloride in chloroform. Saponification of the ester function using methods known in the art such as treatment with a base such as NaOH in solvent mixtures such as EtOH/water provides the corresponding oxa2ole-4-carboxylic acid derivative (26). Scheme 9: Synthesis of carboxylic acids A-COOH wherein A represents an oxazole-4-yl derivative Carboxylic acid derivatives A-COOH wherein A represents a phenyl-2-yl derivative are commercially available or can be synthesised according to sch^tie 10. Scheme 10: Synthesis of carboxylic acids A-COOH wherein A represents a phenyl-2-yl derivative Reaction of commercially available (2-carboxyphenyl)-boronic acid derivatives (27) or esters thereof with commercially available aryl-bromides or aryl-iodldes of formula D-Br or D-l in presence of a catalyst such as Pd(PFfh3)4 and a base such as NaaCOa under heating in a solvent such as toluene, dioxane, THF provides, after saponification, if needed, of the ester using well known methods, the corresponding phenyl-2-carboxylic acid derivatives (28). Alternatively, reaction of commercially available 2-bromo-, or 2-iodo-benzoic acid, or esters thereof, with commercially available boronic acid derivatives of formula D-B(0H)2 using the conditions described before provides the corresponding phenyl-2-carboxyllq acid derivatives (28). Synthesis of Carboxyllc Acids R2-COOH Carboxylic acids of formula R2-COOH are commercially available or well known in the art (Lit. e.g. WO2001/96302; T. Eicher, S. Hauptmann "The chemistry of Heterocycles: Structure, Reactions, Syntheses, and Applteations", 2nd Edition 2003, Wiley, ISBN 978-3-527-30720-3). Carboxylic acid derivatives R2-COOH which represent an an imidazo[2,1-b]thiazole-2-carboxylic acid or an imidazo[2,1-b]thiazole-5-carboxylic acid derivative are commercially available or can be synthesised according to scheme 11. Pathway A: By reaction of 2-chloro-3-oxo-butyric acid methyl ester (29) with thiourea the amino-thiazole (30) can be obtained. Transfcjrmation to ester (31) can be accomplished with bromoacetaldehyde, which can be generated In-situ from bromoacetaldehyde diethylacetal under acidic conditions. After saponification with bases such as NaOH the desired acid (32) can be obteined. Pathway B; By heating a compound of structure (33) with A/,A/-dlmethylformamkle dimethylacetal in a solvent such as toluene formamidine derivatives (34) can be obtained. They can be alkylated with ethyl bromoacetate yielding the respective thiazolium bromide (35), which can be cyclised with strong bases such as DBU to the ester (36). Saponification of the ester function using methods known in the art such as treatment with a base such as NaOH in a solvent such as EtOH/water provides the corresponding imidazo[2,1-b]thiazole-5-carboxylic acid derivatives (37). In scheme 11 preferably R' and R" independently represent hydrogen or methyl. Scheme 11: Synthesis of carboxylic acids R2-COOH which represent an imidazo[2,1-b]thiazole-2-carboxylic acid or an imidazo[2,1-b]thiazole-5-carboxylic acid derivative Carboxylic acid derivatives R2-COOH which represent a pyrrolo[2,1-6]thiazole-7-carboxylic acid derivative can be synthesised according to scheme 12 By reaction of 2-methyl8uifanylthiazole (38) with trimethylsilyimethyl trifluoromethanesulfonate followed by cyclisation of the resulting thiazolinium salt by reaction with ethyl propiolate in the presence of caesium fluoride, the pyrrolo{2,1-b]thiazole (39) can be obtained. Saponification of the ester function using methods known in the art such as treatment with a base such as NaOH in a solvent such as EtOH/ water provides the corresponding pyrrolo[2,1-/)]thiazole-7-car'tX)xylic acid derivative (40) (Berry C.R. et al., Organic Letters, 2007,9, 21,4099-410!2). Scheme 12: Synthesis of carboxylic acids R*-COOH which represent a pyrroloI2,1 -b] thiazole-7-carboxylic acid derivative Bromination of (39) by reaction with NBS followed by methylation of the resulting crude ethyl 6-bromo-pyrrolo[2,1-/?]thiazole-7-carboxylate by reaction with dimethylzinc in the presence of a palladium catalyst such as Pd(dppf)Ct2 gave the ester (41). Saponification of the ester function using methods known in the art such as treatment with a base such as NaOH in a solvent such as EtOH/ water provides the corresponding 6-methyl-pyrrolo[2,1 -d]thiazole-7-carboxyllc acW derivative (42). Carboxylic acid derivatives R2-COOH whteh represent a benzothiazole-7'parboxylic acid derivative can be synthesised according to the literature according to scheme13. Scheme 13: Synthesis of carboxylic acids R2-COOH which represent a benzothiazole-7-carboxyllc add derivative By reaction of methyl 3-amlnobenzoate (43) with potassium thlocyanate In the presence of sulfuric acid and crown-ether 18-C-6, the thiourea (44) can be obtained. Cyclisation by reaction with bromine in acetic acid provides the 2-aminobenzothiazole derivative (45). Cleavage of the amino group by reaction with isoamyl nitrite furnishes the ester (46)(WO2005/092890). Saponification of the ester function using methods l4-carboxyllc acid methyl ester derivatives (general procedure) A solution of thioacetamide (132 mmol, 1.0 eq) in MeCN (250 mL) is added to a mixture of the respective 3-chloro-2-oxo-proptonlc acid methyl ester derivative (132 mmol, 1.0 eq) and molecular sieves (4A, 12 g) In MeCN (60 mL). After stirring for 5 h the mixture is cooled in an ice-bath and the obtained precipitate Is filtered off. The residue is washed with cold MeCN, dried, dissolved in MeOIH (280 mL) and stirred at SOX for 6 h. The solvents are removed In yacuo to give the corresponding 2-methyl-thiazole-4-carboxylic acid methyl ester derivatives. 5-Phenyi-2-methyl-thlazole-4-carboxyllc acid methyl ester prepared by reaction of 3-chloro-3-phenyl-2-oxo-proplonic acid methyl ester with thioacetamide. LC-MSr tp = 0.88 min; [M+H]* = 234.23. 2-Methyi-5-m-tolyi-thiazoie-4-carboxyllc acid methyl ester prepared by reaction of 3-chloro-2-oxo-3-m-tolyl-proplonic acid methyl ester with thioacetamide. LC-MS: IR = 0.94 min; [M+H]' = 248.0. 2-Methy(-5-p-tolyi-thlazole-4-carboxylic acid methyl ester prepared by reaction of 3-chloro-2-oxo-3-p-tolyl-propionic acid nnethyl ester with thioacetamide. LC-IVIS: IR = 0.93 min; [IVI+H]" = 248.02. 5-(4-Ethyl-phenyl)-2-methyl-thlazole-4-carlx)xyllc add mtthyl ester prepared by reaction of 3-chloro-3-(4-ethyl-phenyi)-2-oxo-propionic acid methyl ester with thioacetamide. LC-MS: tp = 0.98 min; [M+H]' = 262.1. 5-(3-Fluoro-phenyl)-2-methyl-thlazole-4-carboxyllc acid methyl ester prepared by reaction of 3-chloro-3-(3-fluoro-phenyi)-2-oxo-propionic acid methyl ester with thioacetamide. LC-MS: ta = 0.91 min; IM+H]"^ = 252.1. S-(4-Fluoro-phenyl)-2-methyl-thlazole-4-carboxyllc acid methyl ester prepared by reaction of 3-chloro-3-(4-fluoro-phenyl)-2-oxo-propionic acid methyl ester with thioacetamide. ^H-NMR (CDCI3): 8 = 2.75 (s, 3H); 3.84 (s, 3H); 7.10 (m, 2H); 7.47 (m, 2H). 2-Methyl-5-(3-trifiuoromethyl-phenyi)'thlazole-4-ciirt)oxylic acid methy^ster prepared by reaction of 3-chloro-3-(3-trifluoromethyl-phenyl)-2-oxo-propionic acid methyl ester with thioacetamide. LC-MS: tR = 0.99 min; [M-t-Hr - 301.99. 2-Methyl-S-(4-trlfluoromethyl-phenyl)-thlazole-4-carboxyNc acid methyl ester prepared by reaction of 3-chloro-3-(4-trifluoromefhyl-phenyl)-2-oxo-propionic acid methyl ester with thioacetamide. LC-MS: tn = 0.99 min; [M+H]* = 301.99. 5-(3-Chloro-phenyl)-2-methyl-thiazoie'4-carboxylic acid methyl ester prepared by reaction of 3-chloro-3-(3-chioro-phenyl)-2-oxo-propionic acid methyl ester with thioacetamide. LC-MS: tR = 0.95 min; [M+H]* = 268.0. 5-(4-Chioro-phenyl)-2-methyl-thiazole-4-carboxyllc acid methyl ester prepared by reaction of 3-chloro-3-(4-chloro-phenyl)-2-oxo-propionic acid methyl ester with thioacetamide. LC-MS: tp = 0.94 min; [M+H]* = 267 5-(3-Methoxy-phenyi)-2-methyl-thiazoie-4-carboxyiic acid methyl ester prepared by reactton of 3-chloro-3-(3-methoxy-phenyl)-2-oxo-proplonic acid methyl ester with thioacetamide. LC-MS: tR = 0.90 min; [M+Hr = 26387. 5-(4-Methoxy-phenyl)-2-methyi-thiazole-4-carbO)(ylic acid methyl ester prepared by reaction of 3-chloro-3-(4-methoxy-phfnyl)-2-oxo-propionic add methyl ester with thioacetamide. LC-MS: tR = 0.90 min; [M+Hr = 263.93. 2-Methyl-5-(3,4-dlmethyl-phenyl)-thlazole-4-carboxylic add methyl ester prepared by reaction of 3-chloro-3-(3,4-dimethyl-phenyl)-2-oxo-propionic acid methyl ester witii thioacetamide. LC-I\/IS: tp = 0.96 min; [M+H]^ = 262.34. 2-Methyl-5-(3,4-difluoro-phenyl)-thlazole-4-carboxyllc add methyl ester prepared by reaction of 3-chloro-3-(3,4-difluoro-plienyl)-2-oxo-propionic acid methyl ester with thioacetamide. LC-MS: tp = 0.92 mIn; [M+H]* = 270.29. A.1.3 Synthesis of 2-amlno-thlazole-4-carboxyllc add methyl ester derivatives (general procedure) A solution of the respective 3-chloro-2-oxo-propionic acid methyl ester derivative (22.1 mmoi, 1.0 eq) in acetone (25 mL) is added to a suspension of thiourea (22.1 mmol, 1.0 eq) in acetone (45 mL). The mixture is heated to 57*C (bath temperature), stirred for 24 h and concentrated to half of the volume. The obtained suspension is filtered and the residue is washed with acetone. After drying the desired amlno-thiazole derivative is obtained as a solid. 2-Amlno-5-m-tolyl-thlazole-4-carboxyllc add methyl ester prepared by reaction of 3-chloro-2-oxo-3-m-tolyl-pr0pionic acid methyl ester with thiourea. LC-MS: tfi = 0.78 min; [M+Hr = 24i9.0. 2-Amlno-5-(3-fluoro-phenyl)-thiazole-4-carboxyllc add methyl ester i prepared by reaction of 3-chloro-3-(3-fluoro-phenyl)-2-oxo-propionic acid methyl ester with thiourea, LC-MS: IR = 0.78 min; [M+HJ* = 252.9. 2-Amlno-5-(4-fluoro-phenyl)-thlazole-4-carboxyllc add methyl ester prepared by reaction of 3-chioro-3-(4-fluoro-phenyl)-2-oxo-propionic acid methyl ester with thiourea. LC-MS: ta = 0.75 min; [M+H]^ = 253. 2-Amino-5-phenyl-thiazoie-4-carboxylic acid rnetiiyi ester prepared by reaction of 3-chloro-3-phenyl-2-oxo-proplonlc acid methyl ester with thiourea. LC-MS: tp = 0.77 min; [M+H]' = 235. A. 1.4 Synthesis of thlazole-4-carboxylic acid derivatives (general procedure) A solution of the respective thiazole-4-carboxyllc acid methyl ester (96.2 mmd) In a mixture of THF (150 mL) and MeOH (50 mL) is treated with 1M aq. NaOH (192 mL). After stirring for 3 h a white suspension is formed and the org. volatiles are removed in vacuo. The remaining mixture is diluted witln water (100 mL^, cooled in an ice-bath and acidified (pH = 3-4) by addition of 11VI aq. HC1- The suspension is filtered and the residue is washed with cold water. After drying the corresponding thiazole-4-carboxylic acid derivative is obtained. 2-Methyl-5-phenyl-thiazoie-4-carboxyllcacici prepared by saponification of 2-methyl-5-phenyl-thiazole-4-tiart)oxylic acid methyl ester. LC-MS: tfi = 0.78 min; [M+Hf = 220.01. 2-Methyl-5-m-tolyl-thiazo(e-4>carboxylic acid prepared by saponification of 2-methyl-5-m-tolyl-thiazole-4-carboxylic acid methyl ester. LC-MS: tR = 0.83 min; [M+Hr = 234.0. 2-Methyl-5-p-tolyl-thlazole-4-carboxylic acid prepared by saponification of 2-methyl-5-p-tolyl-thiazole-4-carboxylic acid methyl ester. LC-MS: tp = 0.83 min; [M+H]' = 234.0. 5-(4-Etliyl-phenyl)-2-niethyl-thiazole-4-carboxyHc acid prepared by saponification of 5-(4-ethyl-phenyl)-2-methyl-thlazole-4-carboxylic acid methyl ester. LC-I\/IS: tp = 0.88 min; [M+H]' - 248.0. 5-(3-Fluoro-piienyl)-2-metliyl-tiiiazole-4-carboxyilcacid prepared by saponification of 5-(3-fluoro-phenyl)-2-methyl-thlazole-4-cart>oxyllc acid methyl ester. LC-MS: tR = 0.82 min; [M+H]' = 238.1. 5-(4-Fiuora-phenyi)-2-metliyi-tliiazoie^-carboxylicacid prepared by saponification of 5-(4-fluoro-phenyl)-2-methyl-thiazole-4-carboxyllc acid methyl ester. 'H-NMR (DMSO-de): 8 = 2.67 (s, 3H); 7.27 (m. 2H); 7.53 (m. 2H); 12.89 (br.s, IH). 5-(3-Chloro-plienyl)-2-methyl-thiazolM-carboxyitcacld prepared by saponification of 5-(3-chloro-phenyl)-2-methyl-thiazole-4-carboxylic acid methyl ester. LC-MS: tR = 0.84 min; IM+Hr = 254.6. 5-(4-Cliloro-phenyl)-2-inethyl-thiazole-4-carboxyllc acid prepared by saponification of 5-(4-chloro-phenyl)-2-meth^-thlazote-4-carboxyllc acid methyl ester. LC-MS: tf, = 0.85 min; [M+H]* = 253. 2-Methyl-5-(3-trlfluorometliyl-phenyl)-thiazole-4-carboxylicacld prepared by saponification of 2-methyl-5-(3-trifluoromethyl-phenyl)-thlazole-4-carboxylic acid methyl ester. LC-MS: tp = 0.88 min; [M+Hl* = 287.99. 2-Methyl-5-(4-trlfluoromethyl-phenyl)-thiazole-4-carboxylicactd prepared by saponification of 2-methyl-5-(4-trlfluoromethyl-phenyl)-thiazole-4-carboxylic acid methyl ester. LC-IVIS: tp = 0.90 min; [M+H]* = 287.99. 2-Methyi-5-(3-methoxy-phenyl)-thlazole-4-carboxylic acid prepared by saponification of 2-methyl-5-(3-metlioxy-phenyl)-thia2ole-4-carboxylic acid methyl ester. LC-MS: tp = 0.80 min; [M+H]^ = 250.04. 2-Methyl-5-(4-methoxy-phenyl)-thiazoie-4-carboxylicacid prepared by saponification of 2-methyl-5-(4-methoxy-phenyl)-thiazole-4-carboxyllc acid methyl ester. LC-MS: tR = 0.80 min; [M+Hr = 250.04. 2-Methyl-5-(3,4-dimethyl-phenyl)-thiazole-4-carboxyllcacid prepared by saponification of 2-methyl-5-(3,4-dimethyl-phenyl)-thlazole-4-carboxylic acid methyl ester. LC-MS: IR = 0.97 min; [M+H]* = 382.38. 2-Methyl-5-(3,4-dlfluoro-phenyl)-thiazole-4-carboxyllc acid prepared by saponification of 2-methyl-5-(3,4-difluoro-phenyl)-thiazole-4-carboxylic acid methyl ester. LC-MS: tR = 0.82 min; [M+H]' = 256.25. 2-Amino-5-m-toiyi-thlazoie-4-carboxyilcacid prepared by saponification of 2-amino-5-m-tolyl-thia2ole-4-carboxylic acid methyl ester. LC-MS: tR = 0.65 min; [M+Hr = 235.0. 2-Amfno-5-(3-fluoro-phenyl)-thlazole^carboxyllcacid prepared by saponification of 2-amino-5-(3-fluoro-phenyl)-thiazole-4-carboxylic acid methyl ester. LC-MS: tR = 0.62 min; [M+H]' = 239.1. 2-Amino-5-(4-fluoro-phenyi)-tliiazole-4-carboxylicacid prepared by saponification of 2-amino-5-(4-fluoro-phenyl)-thia2ole-4-carboxylte acid methyl ester. LC-MS: IR = 0.61 min; [M+H]' = 239. 2-Amino-5-plienyl-tlilazoie-4-carboxylicacid prepared by saponification of 2-amino-5-phenyl-thia2ole-4-carboxyllc add methyl ester. LC-MS: IR = 0.63 min; [M+H]^ = 221. A.2 Synthesis of (1S,2S,5R)-2-aminomethyl-3-aza-blcyclo[3.3.0]-octane-3-carboxyiic acid feft.-butyl ester A.2.1 Synthesis of (1S,2S,5R)-2-hydroxymethyl-3-aza-blcyclo[3.3.0]-octane-3-carboxyllc acid ferf.-butyi ester A mixture of (1S,2S,5R)-3-benzyl-2-hydroxymethyl-3-aza-bicyclo[3.3.b]-octane (synthesized according to WO2003/062265) (350 mg), Pd-C (50% HgO) (300 mg), B0C2O (494 mg, 1.5 eq) In EA (14 mL) was stirred under hydrogen (1 bar) for 16 h. After filtration through celite and removal of the solvents the title compound was obtained as a yellow oil. 'H-NMR (CDCI3): 8 = 1.45 (s, 9H); 1.55-1.85 (m, 5H); 2.15 (m, 1H); 2.55 (m. 1H); 3.25-3.75 (m,5H); 4.6 (m,1H). A.2.2 Syntliesis of (1S,2S,5R)-2-foritiyl^3-aza-blcyclo[3.3.0]-octane^-carboxylic acid ferf.-butyi ester To a cold (-60°C) solution of oxalyl chloride (0.14 mL, 1.2 eq) in dry DCM (3.7 mL) was added dropwise a solution of DMSO (0.215 mL, 2.2 eq) in dry DCM (2.9 mL) within 4 min. After 10 min, was added dropwise (1S,2S,5R)-2-hydroxymethyl-3-aza-bicyclo[3.3.0]-octane-3-carboxylic acid ferf.-butyl ester (330 mg) in dry DCM (1.7 mL) during 5 min. After 2 min a white suspension was formed. Stirring was continued 30 min at -55''C, then DIPEA (1.17 mL, 5 eq) (which was dried over 3A M.S.) was added during 3-4 min. The reaction mixture was allowed to come to RT, diluted with water and extracted with DCM. The combined org. extracts were washed with citric acid (5%), brine, dried over anh. MgS04, filtered and evaporated to yield tlw title compound as an oil which was used for the next step without further purificc^tion. ^H-NMR (CDCI3): 5 = 1.45-1.95 (m, 15H); 2.65 (s, 2H); 3.25-3.55 (m, 3H); 9.45 (s, 1H). A.2.3 Synthesis of (1S,2S,5R)-2-(benzyiamino-methyl)-3-aza-bicyclo[3.3.0]-octane-3-carboxylic acid fert.-butyl ester Benzylamine (0.263 mL, 1.75 eq) was added to a solution of (1S,2S,5R)-2-fomnyl-3-aza-bicyclo[3.3.0]-octane-3-carboxylic acid terf.-butyl ester (330 mg, 1 eq) in chloroform (10 mL). After 15 min the mixture was treated with NaBH(0Ac)3 (292.25 mg, 1 eq), stirred for 2 h and poured into a sat. aq NaHCOa solution. The layers were separated and the aqueous layer was extracted twice with chloroform. The combined org. extracts were washed with sat. NaHCOa solution, dried over anh. MgS04, filtered and concentrated in vacuo to give a crude yellow oil. FC (EA/n-heptane: 3/7 to 7/3) gave the title compound as a colourless oil LC-MS: tR = 0.86 min; [M+H]' = 331. A.2.4 Synthesis of (1S,2S,5R)-2-amlnomethyl-3-aza-bicyclo[3.3.0]-octan»-3-carboxylic acid tert.-butyl ester A solution of (1S,2S,5R)-2-(benzylamino-methyl)-3-a2a-bicyclo{3.3.0]-oqtarje-3-carboxylic acid tert. -butyl ester (354 mg) In EtOH (17 ipL) was treate^l with ff^/C 10% (141 mg) and stirred under hydrogen (1 bar) for 16 i). After filtratlqn throggfi ceiite and removal of the solvents the title compound was obtained as an oil which was used without further purification. ^H-NMR (CDCI3): 8 = 1.25-1.95 (m, 13H); 2.35-2.85 (m, 5H); 3-25-3.65 (m, 4H). A.3 Synthesis of (1S,2S,5R)-2-aminomethyl-7-methyl-3-aza-blcyclo[3.3.0]-octane-3-carboxyiic acid feit.-butyl ester A.3.1 Synthesis of (1R,3aS,3bS,6aR)-5-methyl-1-phenyt-hexahydro-2-oxa-7a-aza-cyciopenta[a]pentalen-7-one A solution of (1R,3aS,3bS,6aR)-5-methyl-1-phenyl-3a,3b,6,6a-tetrahydro-3H-2-oxa-7a-aza-cyclopenta[a|pentalen-7-one (Jao E. et al Tetrahedron Letters, 2003, 44, 5033-5035) (2.34 g) in EtOH (23 mL) was treated with Pd/C 10% (456 mg) and stirred under hydrogen (1 bar) for 1.5 h. After filtration through celite and rpmoval of the solvents the title compound was obtained as ^an oil, which was used, without further purification. ^H-Niy/IR (CDCia): 8 = 1.05-1.35 (m, 5H); 2.05-2.75 (m, 4H); 3.15-3.85 (m, 3H); 4.35 (s, 1H); 6.45 (s, 1H); 7.3-7.5 (m, 5H). A.3.2 Synthesis of (1S^S,5R)-3-benzyl-2-hydroxymethyi-7-methyi-3-aza-bicyclo[3.3.0]-octane To a cold (O'C) solution of (1R,3aS,3bS,6aR)-5-methyi-1-phenyl-hexahydro-2^oxa-7a-aza-cyclopenta[a]pentalen-7-one (470 mg) jn anh. THF (7 mL) was added LAH (160 mg, 2.3 eq) in small portion. The mixture then refluxed for 6 h before cooled to 0''C. To the reaction mixture were carefully added water (0.3 mL), aqueous NaOH solution (15%) (0.9 mL) and water (0.3 mL). The resulting solid was removed by filtration and the filtrate was concentrated in to yield a crude oil. FC (DCM/ IVIeOH: 97/3 to 93/7) gave the title compound as a colourless oil. LC-MS: tR = 0.69 min; [M+Hf = 246. A.3.3 Synthesis of (1S,2S,5R)-2-hydroxymethylH7-methyl-3-aza-blcyclO[3^.0]- octane-3^carboxyllc acid fort-butyl ester I i A mixture of (1S,2S,5R)-3-benzyl-2-hydroxymethi^|t-7-methyl-3-aia-blcyclclit3.3.0]-octane (342 mg), Pd-C (50% HgO) (277 mg), BocaO (456 mg, 1.5 eq) in EA (13 mL) was stirred under hydrogen (1 bar) for 16 h. After filtration through celite and removal of the solvents the title compound was obtained as a yellow oil. ^H-NMR (CDCI3): 5 = 1.05 (m, 3H), 1.45 (s, 9H); 2.05-2.55 (m, 6H); 3.25-3.75 (m, 5H);4.45(m, 1H). A.3.4 Syntliesis Of (1S,2S,5R)-2-formyi«7-methyl'^-aza-bicycio[3.3.0]-bctane-3-cart}oxyllc acid te/f.-butyl ester To a cold (-eO'C) solution of oxalyl chloride (0.081 mL, 1.2 eq) in dry DCM (2.2 mL) was added dropwise a solution of DMSO (0.13 mL, 2.2 eq) in dry DCM (1.7 mL) within 4 min. After 10 min, was added dropwise (1S,2S,5R)-2-hydroxymethyi-7- methyl-3-aza-bicyclo[3.3.0]-octane-3-carboxylic acid fe/t.-butyl ester (206 mg) In dry DCM (1.2 mL) during 5 min. After 2 min a white suspension was formed. Stirring was continued 30 min at -55''C, then DIPEA (0.690 mL, 5 eq) (which was dried over 3A M.S.) was added during 3-4 min. The reaction mixture was allowed to come to RT, diluted with water and extracted with DCM. The combined org. extracts were washed with citric acid (5%), brine, dried over anh. MgS04, filtered and evaporated to yield the title compound as an oil, which was used for the next step without further purification. ;! i| ^H-NMR (CDCI3): 8 = 1.05 (m, 3H), 1.25-1.35 (m, SH); 1.45 (d, QU); 1.9l-i.25 (m, 3H); 2.55 (m, 2H); 3.25-4.15 (m, 3H); 9.45 (s, 1H). A.3.5 Synthesis of (1S,2S,5R)-2-(benzylanilno-methyl)-7-methyl-3-aza-blcyclo[3.3.0]-octane-3-carboxyllc acid fe/f.-butyl ester Benzylamine (0.155 mL, 1.75 eq) was added to a solution of (1S,2S,5R)-2-formyl-7-methyi-3-aza-bicyclo[3.3.0]-octane-3-carboxylic acid fert-butyl ester (206 mg, 1 eq) in chloroform (6 mL). After 15 min the mixture was treated with NaBH(0Ac)3 (173 mg, 1 eq), and stirred for 16 h. The reaction mixture was poured into a sat. aq. NaHCOa solution. The layers were separated and the aq. layer was extracted twice ■ with chloroform. The combined org. extracts were washed with sat. NaHCOs solution, dried over anh. MgS04, filtered and concentrated in vacuo to give a crude yellow oil. FC (EA/ n-heptane: 3/7 to 7/3) gave the title compound as a colourless oil LC-MS: tH = 0.89 min; [M+Hf = 345. A.3.6 Synthesis of (lS,2S.5R)-2-amlnomethyl-7-methyl-3>8za-blcycio[3.3.0]-octane-3-carboxylic acid (erf.-butyl ester A solution of (1S,2S,5R)-2-(benzylamino-methyl)-7-methyl-3-a?a-bicyq|o[3.3.0]-octane-3-carboxylic acid te/t.-butyl ester (264 mg) in itOH (12 mL) was treated with Pd/C 10% (100 mg) and stirred under hydrogen (1 bar) for 16 h. After filiation through celite and removal of the solvents the title compound was obtained as a colourless oil which was used without further purification. 'H-NMR (CDCIa): 8 = 0.95 (m, 3H); 1.35(m, 2H); 1.45 (s, 9H); 1.85-2.45 (m, 8H); 3.25-3.75 (m, 2H). A.4 Synthesis of 3-acyl-sub8tltuted (1S,2S,SR)-2-(amino-metfiyl)-S-aza-blcyclo[3.3.0]-octane derivatives A.4.1 Synthesis of (lS,2S,5R)-2-[(2,2,2-trlfluoro-acetylamlno)-niethyl]-7-methyl-3-aza-blcyclo[3.3.0]-octane-3-carboxyllc add tert.-butyl ester Ethyl trifluoroacetate (0.7 mL, 1.4 eq) was added to a solution of (lS,2S,5R)-2-aminomethyl-7-methyl-3-aza-bicyclo[3.3.0]-octane-3-carboxylic acid tert.-butyl ester (1.1 g) in dry THF (14 mL). The reaction mixture was stirred at RT for 1 h. Solvent and excess ethyl trifluoroacetate were evaporated in vacuo. The resulting product was then used for the next step without purification LC-MS: tR = 1.04 min; [M+H]' = 351. A.4.2 Synthesis of N-[(1S,2S,5R)-7-methyl-3-azaoxyllc acid tert.-butyl ister ^ prepared by reaction of (1S,2S,5R)-1-aminomethyl-3-aza-bicyclo[3.3.0]-octane-3-carboxylic acid tert.-butyl ester with commercially available benzo[fl(|isoxazole-3-carboxylic acid. LC-IVIS: tR = 1.03 min; [M+Hr = 386. (lS,2S,5R)-2-{[(liiiidazo[2,1-l>]thiazole-5-carbonyl)-amino]>methyi}-3-aza- ■ bicyclo[3.3.0]octane-3-carboxylic acid teit.-butyl ester prepared by reaction of (1S,2S,5R)-1-aminomethyl-3-aza-blcycld[3.3.0]-octane-3-carboxylic acid tert.-butyl ester with imidazo[2,1-/j]thiazole-5-carboxylic acid which was synthesised by saponification of the corresponding ethyl ester derivative (W01995/029922) with NaOH in a mixture water/EtOH. LC-MS: tR = 0.90 min; [M+H]' = 391. (lS,2S,SR)>2-{[(Benzoi[fiQisothiazole-3-carbonyl)-aminoI-iiiethyl}-3-aza-blcyclo[3.3.0]octane-3-carboxyllc acid tert.-butyl ester prepared by reaction of (1S,2S,5R)-1-aminomethyl-3-aza-blcyclo[3.3.0]-octane-3-carboxylic acid ferf.-butyl ester with benzo[c(iisothiazole-3-carboxytic acid (WO2004/029050). LC MS: tR = 1.08 min; [M+Hr = 402. (1 S,2S,5R)-2-{[6-Methyl-(imlciazo[2,1 -b]thiazole-5-carbonyl)-amlno]-methyl}-7-methyl-3-aza-bicyclo[3.3.0]octane-3-carboxylic acid tert.-butyl ester prepared by reaction of (1S,2S,5R)-2-aminomethyl-7-methyl-3-a2a-bicyclo[3.3.0I-octane-3-carboxylic add fert.-butyl ester with commercially available 6-methyl-imidazo[2,1-i)]thiazole-5-carboxylic acid. LC-MS: tn = 0.93 min; [M+Hr = 419. (1S,2S,5R)-2-{[(3,4-Dihydro-benzo[1,4]dioxlne-5-cffi'bonyl)-ainino]-methyl>-7-methyl-3-aza-blcyclo[3.3.0]octane-3-carboxyllc acid tert.-biityl ester prepared by reaction of (1S,2S,5R)-1-aminomethyl-7-methyl-3-aza-blcyclo[3.3.0J-octane-3-carboxylic acid tert.-butyl ester with commercially available 2,3-dlhydro-benzo[1,4]dioxine-5-carboxylic acid. LC-MS: tR = 1.03 min; [M+Hr = 417. (1S,2S,5R)-2-{[(Benzo[d]lsoxazole-3-carbonyl)-amlno]'methyl}-7-methyl-3-aza-bicyclo[3.3.0]octane-3-carboxylic acid tert.-butyl ester prepared by reaction of (1S,2S,5R)-1-aminomethyl-7-methyl-3-aza-bicyclo{3.3.0]-octane-3-carboxyllc acid tert.-butyl ester yvith commercially available benzo[dJisoxazole-3-carboxylic acid. LC-MS: tR = 1.06 min; [Mf = 399. (1 S,2S,5R)-2-{[(lmldazo[2,1 -d]thlazole-5-carbonyl)-amino]»methyl}-7-methyl-3-aza-blcyclo[3.3.0]octane-3-carboxylic add tert.-butyl ester prepared by reaction of (1S,2S,5R)-1-amlnomethyl-7-methyl-3-aza-bicyclo[3.3.0]-octane-3-carboxylic add fe/t.-butyl ester with imidazo[2,1-dJthiazole-5-carboxylic acid whicli was synthesised by saponification of the corresponding ethyl ester derivative (W01995/029922) with NaOH in a mixture water/EtOH. LC-MS: tfi = 0.94 min; IM+Hr = 405. (1S,2S,5R)'2-{[(Benzo[cf]l80thlazole-3-carbonyl)-afnino]-methyl}-7-niethy|-3-aza- blcycio[3.3.0]octane-3-carboxyllc acid tert.-butyl ^ter i prepared by reaction of (1S,2S,5R)-1-aminomethyl-7-methyl-3-aza-bicyck){3.3.0J-octane-3-carboxylic acid fe/t.-butyl ester with benzo[c()isothiazole-3-carboxyllc acid 2-ylmethyl]-amide prepared by reaction of 3,4-dihydro-benzo[1,4]dioxlne-5-carboxylic acid-[(1S,2S,5R)-7-methyl-3-aza-bicyclo[3.3.0Joct-2-ylmethyl]-amidewith2-methyl-5-m-tolyl-thiazole-4-carboxylic acid. LC-MS: tR = 1.06 min; [M+H]* = 532. Examples 1-Methyl-lndazole-3-carboxyllc acld-(1S,2S,5R)-[7-methyl-3-(2-methyl-5-m-tolyl-thiazole-4-carbonyl)-3-aza-bicyclo[3.3.0]oct-2-ylmethyl]-amlde prepared by reaction of 1-methyl-1H-indazole-3-carboxylic acid-[(1S,2S,5R)-7-methyl-3-aza-bicyclo[3.3.0]oct-2-ylmethyl]-amide with 2-methyl-5-m-tolyl-thiazole-4-carboxylic acid. LC-MS: tn = 1.07 min; [M+H]* = 528. Examples 3,S-Dimethyl-i8oxazole-4-carboxylic acid-(1S,2S,5R)-[7-methyl-3-(2-inethyl-5-/n- tolyl-thiazole-4-carbonyl)-3-aza-bicyclo[3.3.0]-2-ylmethyl]-amlde , . prepared by reaction of 3,5-dlmethyl-isoxazole-4-carboxylic acid-[(1S,2S,5R)-7-methyl-3-aza-bicyclo[3.3.0]oct-2-ylmethyl]-amide with 2-methyl-5-m-tolyl-thiazole-4-carboxylic acid. LC-MS: tR = 1.03 min; [M+HK = 493. Example 7 Benzo[c/]l80xazole-3-carboxyllc aclcl-(1S,2S,5R)-[7-methyl-3-(2-methyl-5-m-tolyl-thlazole-4-carbonyl)-3-aza-blcyclo[3.3.0]oct-2-ylmethyl]-amlde prepared by reaction of benzo[af]isoxazole-3-carboxylic acid-[(1S,2S,5R)-7-methyi-3-aza-bicyclo[3.3.0]oct-2-ylmethyl]-amide with 2-methyl-5-m-tolyl-thiazole-4-carboxylic acid. LC-MS: tR = 1.07 min; [iVI+Hr = 515. Examples Benzo[d]l8oxazole-3-carboxylic acld-(1S,2S,5R)-[3-(2-methyl-5-m-toiyl-thlazole-4-carbonyl)-3-aza-blcyclo[3.3.01oct-2-ylmethyl]-amlde prepared by reaction of benzo[c/]isoxazole-3-carboxylic acid-[(1 S,2S,5R)-3-aza-bicyclo[3.3.0]oct-2-ylmethyl]-amide with 2-methyl-5-m-tolyl-thiazole-4-carboxylic acid. LC-MS: tp = 1.04 min; [M+Hr = 501. Example 9 Benzo[d]l8othlazole-3-carboxylic acid-(1S,2S,5R)-[7-methyl-3-(2-methyl-S-m-tolyl-thlazole-4-carbonyl)-3-aza-blcyclo[3.3.0]oct-2-ylmethyl]-amlde prepared by reaction of benzo[flf]i8othiazole-3-carboxylic acld-[(1S,2S,5R)-7-methyl-3-c7a-bicyclo[3.3.0]oct-2-ylmethyl]-amide with 2-methyl-5-m-tolyl-thiazole-4-carboxylic acid. LC-MS: tp = 1.12 min; [M+H]* = 531. Example 10 Benzo[d]isothiazole-3-carboxylic acld-(1S,2S,5RH3-(2-methyl-5-m-tolyl- thlazole'-4-carbonyl)-3-aza-blcyclo[3.3.0]oct-2-ylmethyl]-amlde prepared by reaction of benzo[dJisothiazole-3-carboxyfic acld.-[(lS,2S,5R)-3-aza-bicyclo[3.3.0]oot-2-ylmethyl]-amide with 2-methyl-5-m-tolyl-thiazole-4-carboxylic acid. LC-MS: tfl = 1.08 min; [M+Hr = 517. Example 11 1 ' lmldazo[2,1-d]thlazole-5-carboxyllc acld-(1S,2S,SR)-[7Hmethyl-3-(2-m^h]^-5-m-to!yl-thiazole-4-carbonyl)-3-aza-bicyclo[3.3.0]oct-2-ylmethyl]-amlde prepared by reaction of witli imida2o[2,1-b]tliiazole-5-carboxyllc acid-[(1S,2S,5R)-7- methyl-3-aza-bicyclo[3.3.0]oct-2-ylmethyl]-amide 2-methyl-5-m-tolyl-tlilazole-4- carboxylic acid. LC-MS: tR = 0.95 min; [M+Hr = 520. Example 12 lmidazo[2,1-l)]thlazole-5-carboxyllc acld-(1S,2S,5R)-[3-(2-methyl-5-m-tolyl-thlazole-4-carbonyl)-3-aza-blcyclo[3.3.0]oct-2-ylmethyl]-amlde prepared by reaction of imidazo[2,1-b]thiazole-5-carboxylic acld-[(1S,2S,5R)-3-a2a-bicyclo[3.3.0]oct-2-ylmethyl]-amide with» 2-metliyl-5-m-tolyl-thlazole-4-carboxylic add. LC-MS: tfi = 0.92 min; {M+Hr = 506. Example 13 imidazo[2,1-d]thlazole-6-carboxyllc acld-(1S,2S,5R)-|7-metliyl-3-(2-methyl-5-m-tolyl-thlazole-4-carbonyl)-3-aza-bicyclo[3.3.0]oct-2-ylmethyi]-amide prepared by reaction of imidazoI2,1-6]thiazole-6-carboxylic acid-[(1S,2S,5R)-7-methyl-3-aza-bicyclo[3.3.0]oct-2-ylmethylJ-amide wijh 2-methyl-5-/n-tolyl-^hia?ole-4-carboxylic acid. LC-MS: tR = 0.98 min; [M+Hr = 520. Preparation of Examples (general procedure II) To a soiution of tlie respective carboxylic acid derivative R2-COOH (1 eq) in DMF (0.6 ml7 0,2 mmol) are added successively DIPEA (5 eq) and TBTU (1 eq). The reaction mixture is stirred for 15 min. and then a solution of the respective 3-acyl-substituted (1S,2S,5R)-2-(amlno-methyl)-3-aza-bicyclo[3.3.01-octane derivative (Intermediate A.4, 1 eq) or (1S,2S,5R)-(2-aminomethyl-7,7-clifluoro-3-aza-bicyclo[3.3.0]-oct-3-yl)-(2-methyl-5-m-tolyl-thiazol-4-yl)-methanone (intermediate A.6, 1 eq) in DMF (0.6 mU 0.2 mmol) is added. The mixture Is stirred over night and purified by prep. HPLC to give the respective final compounds. The compounds of the following examples have been prepared using general procedure II. Example 14 (1 S,2S,5R)-3-Bromo-/V-[7-methyl-3-(2-methyl»5-m-tolyl-thlazoie-4-carbonyl)-3-aza-b>cyclo[3.3.0]oct-2-ylmethyl]-benzamide . prepared by reaction of [(1 S,2S,5R)-2-aminomethyl-7-methyl-3-aza-bicyclo[3.3.0]oct-3-yl]-(2-methyl-5-m-tolyl-thiazol-4-yl)-methanone with 3-bromo-benzoic acid. LC-MS: tR = 1.08 min; [M+Hr = 554. Example 15 (1S,2S,5R)-3-Chloro-iV-|7-methyl-3-(2-methyl-5-m-tolyl>thlazole^carbonyl)-3-aza-blcyclo[3.3.0]oct-2-ylmethyl]-benzamlde prepared by reaction of [(1S,2S,5R)-2-aminomethyl-7-methyl-3-aza-bicyclo[3.3.0]oct-3-yl]-(2-methyl-5-m-tolyl-thiazol-4-yl)-methanone with 3-chloro-benzoic acid. LC-MS: tR = 1.14 min; [M+Hf = 509. Example 16 (1S,2S,5R)-3-Fluoro-/V-[7-methyl-3-(2-methyl-5-m-tolyl-thlazole-4-carbonyl)-3-aza-bicyclo[3.3.0]oct-2-ylmethyl]-benzamlde prepared by reaction of [(1 S,2S,5R)-2-aminomethyl-7-methyl-3-aza-blcyclo[3.3.0]oct-3-yl]-(2-methyl-5-/n-tolyl-thlazol-4-yl)-methanone with 3-fluoro-benzoic acid. LC-MS: tR = 1.12 min; [M+Hr = 492. Example 17 (1S,2S,5R)-3-Methoxy-N-[7-methyl-3-(2-methyi-5-m-tolyl-thlazole-4-carbonyl)-3-aza-blcyclo[3.3.0]oct-2-ylmethyl]-benzamlde prepared by reaction of [(1S,2S,5R)-2-aminomethyl-7-methyl-3-aza'blcyclo[3.3.01oct-3-yl]-(2-methyl-5-m-tolyl-thiazol-4-yl)-methanone with 3-methoxy-benzoic acid acid. LC MS: tn = 1.11 min; [M+H]^ = 504. Example 18 (1 S,2S,5R)-A/-[7-Methyl-3-(2-methyl-5-m-tolyl-thiazole-4-carbonyt)-3-aza-blcyclo[3.3.0]oct-2-ylmethyl]-3-trifluoromethyl-benzamide prepared by reaction of [(1 S,2S,5R)-2-aminomethyl-7-methyl-3-aza-bicyclo[3.3.0]oct-3-yl]-(2-methyl-5-m-tolyl-thiazol-4-yl)-methanone with 3-(trifluorometliyl)-benzoic acid acid. LC-iVIS: tR = 1.15 min; IM+Hf = 542. Example 19 (1S,2S,5R)-3-Methyl-A/-|7-methyl-3-(2-methyl-5-/n-tblyl-thiazole-4-carbonyl)-3-aza-blcyclo[3.3.0]oct-2-ylmethyl]-benzamlde prepared by reaction of [(1 S,2S,5R)-2-aminomethyl-7-methyl-3-aza43icyclot3.Q.0]oct-3-yl]-(2-methyl-5-m-tolyl-thiazol-4-yi)-methanone with 3-methyl-benzoic acid, LC-MS: tR = 1.11 min; [M+H]' = 488. Example 20 (1S,2S,5R)-A/-[7-Methyl-3-(2-methyl-5-m-tolyl-thlazole-4-carbonyl)-3-aza-blcyclo[3.3.0]oct-2-ylmethyl]>3-trlfluoromethoxy-benzamlde prepared by reaction of [(1S,2S,5R)-2-aminomethyi-7-methyl-3-aza-bicycloI3.3,0]oct-3-yl]-(2-methyl-5-m-tolyl-thiazol-4-yl)-nf\ethanone with 3-(trifluoromethoxy)-benzoic acid LC-MS: tp = 1.17 min; [M+Hf = 558. Example 21 6-Trlfluoromethyl-pyrldlne-2-carboxyllc acld-(1S,2S,5R)-[7-methyl-3-(2-methyl-5-m-tolyl-thiazole-4-carbonyl)-3-aza-blcyclo[3.3.0]oct-2-ylmethyl]-amlde prepared by reaction of [(1S,2S,5R)-2-aminomethyl-7-methyl-3-aza-bicycloI3.3.0]oct-3-yl]-(2-methyl-5-/T7-tolyl-thiazol-4-yl)-methanone with 6-trifluoromethyl-pyrldine-2-carboxylic acid. LC-MS: tH = 1.14 min; [IVI+Hr = 543. Example 22 if 1 6-Methyl-pyridlne-2-carboxyllc acld-(1 S.2S,5R)-[7-methyl-3-(2-methyl-5-m-tolyl-thlazole-4-carbonyl)-3-aza-blcyclo[3.3.0]oct-2-ylmethyl]-amlde prepared by reaction of [{1S,2S,5R)-2-aminomethyl-7-m0thyl-3-aza-bicyclo[3.3.O}oct-3-yl]-(2-methyl-5-/r7-tolyl-thiazol-4-yl)-methanone with 6-methyl-pyridine-2-carboxylic acid. LC-IVIS; tp = 1.14 min; [M+Hf = 489. Example 23 6-Methoxy-pyrldine-2'-carboxylic acld>(lS,2S,SR)-[7-methyl-3-(2-methyl-5-m-tolyl-thiazole-4-carbonyi)-3-aza-blcyclo[3.3.0]oct-2-ylmethyl]-amlde prepared by reaction of [(1S,2S,5R)-2-aminomethyl-7-methyl-3-aza-bicyclo[3.3.0]oct- 3-yi]-(2-metliyi-5-/r7-tolyi-tliiazoi-4-yl)-methanone with 6-methoxy-pyridine-2- carboxylic acid. i LCVIS:tR=1.13min;[M+Hr = 505. '' Example24 ! i' ' 4-Bromo-pyridlne-2-carboxylic acld-(1S,2S,5R)-[7-m«thyl-3-(2-inethyl'^-m-tolyl-thiazole-4-carbonyl)-3-aza-bicyclo[3.3.0]oct-2-ylmethyi]-amide prepared by reaction of [(1S,2S,5R)-2-aminomethyl-7-m©thyi-3-a2a-bicycloI3.3.0Joct-3-yl]-(2-methyl-5-m-tolyl-thiazoi-4-yl)-methanone with 4-bronr»o-pyridlne-2-carboxylic acid. LC-IVIS: tfi = 1.12 min; [M+Hf = 555. Example 25 4-Chloro-pyrldlne-2-carboxyllc acld-(1S,2S,5R)-[7-methyl-3-(2-methyl-5-m-tolyh thiazole-4-carbonyl)-3*aza-blcyclo[3.3.0]oct-2-ylmettiyl]-amide prepared by reaction of [(1 S,2S,5R)-2-aminomethyl-7-methyl-3-a2a-bicyclo[3.3.01oct-3-yl]-(2-methyl-5-m-tolyl-thlazol-4-yl)-methanone with 4-chloro-pyrldine-2-carboxylic acid. LC-MS: tfi = 1.11 min; [M+Hr = 509. Example 26 4-Methyl-pyridlne-2-carboxylic acld-(18,2S,5R)-^-methyl-3-(2-methyl-5-m-tolyl-thlazole-4-carbonyl)-3-aza-blcyclo[3.3.0]oct-2-ylmethyl]-amlde prepared by reaction of [(1S,2S,5R)-2-aminomethyl-7-methyl-3-azi^-blcycl^[^.3.0]oct-3-yl]-(2-methyi-5-m-toiyl-thiazol-4-yl)-methanone with 4-methyl-pyridine-2-carboxylic acid. LCMS: tR = 1.07 min; [M+H]' = 489. Example 27 (1S,2S,5R)-5-Bromo-A/-[7-Methyl-3-(2-methyl-5-in-tolyl-thiazole-4-carbonyl)-3-aza-bicyclo[3.3.0]oct-2-ylmethyl]-nlcotlnamlde prepared by reaction of I(1S,2S,5R)-2-aminomethyl-7-methyl-3-aza-bicyclo[3.3.0]oct-3-yl]-(2-methyl-5-m-tolyl-thia2ol-4-yl)-methanone with 5-bromo-nicotinic acid. LC-I\/1S: tR = 1.12 min; [IV1+Hr = 555. Example 28 (1 S,2S,5R)-5-Chloro-A/-[7-Methyl-3-(2-methyl-5-in-tolyl-thlazole-4-carbonyl)-3-aza-blcyclo[3.3.0]oct-2-ylmethyl]-nicotlnamicle prepared by reaction of [(1S,2S,5R)-2-amlnomethyl-7-methyl-3-aza-bicyclot3.3.0]oct-3-yl]-(2-methyl-5-m-tolyl-thiazol-4-yl)-methanone with S-chloro-nicotinIc acid. LC-IVIS: tn = 1.11 min; [M+H]" = 509. i ^ ! Example 29 (1S,2S,5R)-5-Methyl-/tf-[7-Methyl-3-(2-methyi-5-m-tolyl-thlazole-4-carbonyi)-3-aza-blcyclo[3.3.0]oct-2-ylmethyl]-nlcotlnamlcle prepared by reaction of [(1 S,2S,5R)-2-aminomethyl-7-methyl-3-aza-bicycloI3.3.0]oct-3-yl]-(2-methyl-5-m-tolyl-thiazol-4-yl)-methanone with 5-methyl-nlcotinlc acid. LC-MS: tR = 0.94 min; [IVI+Hr = 489. Example 30 Berizofuran-4-carboxyllc aclcl-(1S,2S,5R)-[7-methyl-3-(2-methyl-5-m-toiyl- thiazole-4-carbonyl)-3-aza-bicycto[3.3.0]oct-2-ylmethyl]-amlde prepared by reaction of [(1 S,2S,5R)-2-aminomethyl-7-methyl-3-aza-bicyclo[3.3.0]oct-3-yl]-(2-methyl-5-m-tolyl-thia2ol-4-yl)-methanone with benzofuran-4-carboxyllc acid (IVI.A. Eissenstat et al. J. Wed C/je/r?. 1995,5fl, 3094-3105). LC-MS: tR = 1.12 min; [M+Hr = 514. Example 31 2-Methyl-benzofuran-4-carboxyllc acld-(1S,2S,5R)-[7-methyl-3-(2-methyi-5-m-tolyl-thlazole-4-carbonyl)-3-aza-blcyclo[3.3.0]oct-2-ylmethyl]-amlde prepared by reaction of [(1S,2S,5R)-2-aminomethylt7-methyl-3-aza-bicycl(^[3.3.0loct-3-yil-(2-methyl-5-m-tolyl-thiazol-4-yl)-methanone with 2-methyl-benzofuran-4- carboxylic acid which was synthesised by saponification of the corresponding methyl ester derivative ((shikawa T. et al. Heterocycles 1994, 39, 1, 3^1-380) with NaOH in a mixture water/MeOH. LC-I^S: tR = 1.14 min; [M+Hr = 528. Example 32 2-Methyl-benzoxazole-4-carboxylic acld-(1S,2S,5R)-[7-inethyl-3-(2-m9thyl-5-m-tolyl-thiazole-4-carbonyl)-3-aza-blcyclo[3.3.0]oct-2-ylmethyl]-amicle prepared by reaction of [(1S,2S,5R)-2-aminomethyl-7-methyl-3-aza-blcyclo[3.3.0]oct-3-yl]-(2-methyi-5-m-tolyi-thiazoi-4-yl)-methanone with 2-methyt-benzoxazole-4-carboxylic acid which was synthesised by saponification of the corresponding methyl ester derivative (Goldstein S et al. J. of Heterocyclic. Chem. 1990, 27, 2, 335-336) with NaOH In a mixture water/MeOH. LC-MS: tR = 1.12 min; [M+Hf = 529. Preparation of Examples (general procedure I) The compounds of the following examples have been prepared using general procedure I described above. Example 33 6-Methyl-lmidazo[2,1-i)]thlazole-5-carboxyllc acld-(1S,2S,5R)-{3-[5-(3-methoxy-phenyl)-2-methyl-thiazole-4-carbonyl]-3-aza-blcyclo[3.3.0]oct-2-ylmethyi}-amlde prepared by reaction of 6-methyl-imidazo[2,1-/b]thlazole-5-carboxylic acid-[(1S,2S,5R)-3-aza-blcyclo[3.3.0]oct-2-ylmethyl]-amide with 5-(3-methoxy-phenyl)-2-methyl-thiazole-4-carboxyllc acid. LC-MS: tR = 0.88 min; IM+Hr = 536. Example 34 6-Methyl-lmldazo[2,1-d]thias)l«-5-carboxylic acld-(1S4{S,5R)-{3-[5-(3-m«thoxy- phenyl)-2-methyi-thiazole-4-carbonyl]-7-methyl-3-aza-bicyclo[3.3.0]oct-2- ylmethyl}-amlde prepared by reaction of 6-methyl-imidazo[2,1-6]thiazole-5-carboxylic acid-[(1S.2S,5R)-7-methyl-3-aza-bicyclo[3.3.0loct-2-ylmethyl]-amlde with 5-(3-methoxy-phenyi)-2-methyl-thlazole-4-carboxyllcacid. LC-IVIS: tR = 0.92 min; [M+H]* = 550. Example 35 6-[M8thyl-imidazo[2,1-6]thiazole-5-carboxyllc acid-(1S,2S,5R)-{3-[2-methyl-5-(3-trlfluoromethyl-phenyl)-thlazole-4-carbonyl]-3<-aza-bicyclo[3.3.0]oct-2-ylmethyl}-amlde prepared by reaction of 6-methyl-imidazo[2,1-ib]thiazole-5-carboxylic acid- [(1S,2S,5R)-3-aza-bicyclo[3.3.0]oct-2-ylmethyl]-amide with 2-methyl-5-(3- trifluorometliyl-phenyl)-tliiazole-4-carboxylic acid. LC-MS: tR = 0.94 min; [M+Hf = 574. Example 36 6-Methyl-lmldazo[2,1-b]thlazole-5-carboxyilc acid-(1S,2S,5R)-{7-methyl-3-[2-methyl-5-(3-trifluoromethyl-phenyl)-thiazole-4-carbonyl]-3-aza-bicyclo[3.3.0]oct-2-ylmethyl}-amide prepared by reaction of 6-metliyl-imidazo[2.1-b]thiazole-5-carboxylic acid-[(1S,2S,5R)-7-metliyl-3-aza-bicyclo[3.3.0]oct-2-ylmethyl]-amide witli 2-methyl-5-(3-trif luoromethyl-piienyl)-tliiazole-4-carboxylic acid. LC-MS: tR = 0.97 min; [M+H]' = 588. , ^< Example 37 6-Methyl-lmldazo[2,1-d]thiazole-5-carboxylic acld-(1S,2S,5R)-»{3-[5-(3-fluoro-phenyl)-2-methyl-thlazole-4-carbonyl]-3-aza-bicyclo[3.3.0]oct-2ylmethyi}-amlde prepared by reaction of 6-metliyl-imidazo[2,1-b]thiazole-5-carboxylic acid-[(1S,2S,5R)-3-aza-bicyclo[3.3.0]oct-2-ylmethyl]-amide witli 5-(3-ciiloro-piienyl)-2-metiiyl-tiiiazole-4-carboxylic acid. LC-IVIS: tR = 0.92 min; Il\/I+Hr = 540. Example 42 6-Methyl-imldazo[2,1-dlthlazole-5-carboxyllc acld-<18,2S,5R)-{3-[5-(3-chloro- phenyl)-2-methyl-thlazole-4-carbonyl]-7-methyl-3-aza-blcyclo[3.3.0]oct-2- ylmethyl}-amlde prepared by reaction of 6-methyl-imidazo[2,1-b]thlazole-5-carboxylic acid-[(1S,2S,5R)-7-metliyl-3-aza-blcyclo[3.3.0]oct-2-ylmetliyl]-amide witli 5-(3-chloro-phenyl)-2-methyl-thiazole-4-carboxyllc acid. LC-IVIS: tR = 0.95 min; [M+H]" = 554. Example 43 6-Methyl-imiciazo[2,1-()]thiazole-5-carboxyilc acld-(1S,2S,SR)-{3-[5-(4-methoxy-ph«nyl)-2-methyl-thlazole-4-carbonyl]-3-aza-bicyclo[3.3.0]oct*2-ylmethyl}-amlde prepared by reaction of 6-methyl-imidazo[2,1-d]thia20le-5-carboxylic acid-[(1 S,2S,5R)-3-aza-bicyclo[3.3.0]oct-2-ylmethyl]-amide with 5-(4-mettioxy-phenyl)-2-methyl-thiazole-4-cait>oxylicadd. LC-MS: tR = 0.88 min; [IVI+Hr = 536. Example 44 6-Methyl-lmldazo[2,1-i)]thlazole-5-carboxylic acld'(1S,2S,5RH3-[5-(4-methoxy- phenyl)-2-methyl-thiazole-4-carbonyl]-7-methyl-3-aza-bleyclo[3.3.0]oct-2- ylmethyl}-amlde prepared by reaction of 6-metiiyl-imidazo[2,1-d]thiazole-5-carboxylic acid-[(1S,2S,5R)-7-metiiyl-3-aza-blcyclo[3.3.0]oct-2-ylmethyl]-am!de with 5-(4-methoxy-phenyi)-2-methyl-thia2ole-4-carboxyiic acid. LC-IVIS: tR = 0.91 min; [IVI+Hr = 550. Example 45 6-Methyl-lmldazo[2,1-/)]thlazole-5-carboxyllc acid-(1S,2S.5R)-{3-[5-(4-ethyl- phenyl)-2-methyl-thlazole-4-carbonyn-7-methyl-3-aza-blcyclor3.3.0]oct-2- ylmethyl}-amlde prepared by reaction of 6-methyi-imidazo[2,1-/)]thlazoie-5-carboxylic acid-[(1S,2S,5R)-7-methyi-3-aza-bicycloI3.3.0]oct-2-yimethyll-amide with 5-(4-ethyl-phenyl)-2-methyl-thiazole-4-carboxylicacid. LC-IVIS: tR = 0.99 min; [M+Hr = 548. Example 46 6-Methyl-imidazo[2,l-d]thlazole-5-carboxylic acld-(1S^S,5R)-{7-meth^-3-[2« methyl-5-(4-trlfluoromethyl-phenyl)-thlazole-4-carbonyl]'3-aza-blcyclo[3.3.0]oct-2-ylmethyl}-amlde prepared by reaction of 6-methyi-imidazo[2,1-d]thiazoie-5-carboxyiic acid-[(1S,2S,5R)-7-methyl-3-aza-bicyclo[3.3.0]oct-2-ylmethylJ-amide with 2-methyl-5-(4-trif iuoromethyi-phenyi) -thiazole-4-carboxyiic acid. LC-!VIS: tR = 0.98 min; [l^+Hr = 588. Example 47 6-Methyl-lmldazo[2,1-6]thlazole-5-carboxyllc a(^ld-(1S,2S,5RH3-[5-(4-fluoro- phenyl)-2-methyl-thiazole-4-carbonyl]-7-methyl-3-aza-bicyclo[3.3.0]oct-2- ylniiathyl}-amide prepared by reaction of 6-methyl-imidazo[2,1-/3]thiazo|e-5-carboxylic acid-[(1S,2S,5R)-7-methyl-3-aza-bicyclo[3.3.0]oct-2-ylmethyl]-amide with 5-(4-fluoro-phenyl)-2-methyl-thiazole-4-carboxylicacid. LC-IVIS: tR = 0.93 min; [IVI+Hr = 538. Example 48 6-Methyl-lmldazo[2,1-()]thlazole-5-carboxyllc acid-(1S,2S,5R)-{7-methyl-3-[2-methyl-5-phenyl-thlazole^-carbonyl]-3-aza-bicyclo[3.3.0]oct'2-ylmethy[}-amlde prepared by reaction of 6-metiiyl-imldazo[2,1-Jb]thiazole-5-carboxylic acid-[(1 S,2S,5R)-7-methyl-3-aza-bicyclo[3.3.0]oct-2-ylmet»iyl]-amide witti 2-metliyl-5-plienyl-thiazole-4-carboxylicacld. LC-I\^S: tR = 0.92 min; [IVI+Hr = 520. Example 49 6-Methyl-lmidazo[2,1-i)]thlazole-5-carboxylic acid-(1S,2S,5RH3-[5-(3,4- dimethyl-phenyl)-2-methyl-thlazole-4-carbonyl]-7-methyl-3-aza- bicyclo[3.3.0]oct-2-ylmethyl}-amlde i ■ prepared by reaction of 6-metliyl-imidazo[2,1-b]tliiazole-5-carboxyiic acid-[(1S,2S,5R)-7-metliyl-3-aza-bicyclo[3.3.0]oct-2-yimetliyl]-amide with 5-(3,4-dlmethyl-phenyl)-2-methyl-thiazole-4-carboxylic acid. LC-IVIS: tn = 0.98 min; [l^+H]' = 548. Example 50 6-Methyl-lmldazo[2,1-A]thlazole-5-carboxyllc acld-(1S,2S,5R)-{3-[S-(3,4- dlmetliyl-phenyl)-2-methyl-thlazole-4-carbonyl]-3-aza-bicyclo[3.3.0]oct-2- ylmethyl}-amlde prepared by reaction of 6-methyl-imidazo[2,1-b]thiazole-5-carboxylic acid-[(1S,2S,5R)-3-aza-bicyclo[3.3.0]oct-2-yimethyl]-amide with 5-(3,4-dimethyi-phenyi)-2-methyl-thiazoie-4-carboxylic acid. LC-MS: tn = 0.94 min; [M+HY = 534. Example 51 j ' ,, 6-Methyl-imidazo[2,1-i)]thlazole-5-carboxyllc acld-(1S,2S,5R)-{3-|5-(3,4-difluoro- phenyl)-2-methyl-thlazole-4-carbonyl]-7-methyl-3-aza-bicycio[3.3.0]oct-2- ylmethyl}-amlde prepared by reaction of 6-methyl-imidazo[2,1-jb]thiazole-5-carboxylic acid-[(1S,2S,5R)-7-methyl-3-a2a-bicyclo[3.3.0]oct-2-ylmethyl]-am}de with 5-(3,4-difluoro-phenyl)-2-methyl-thiazole-4-carboxylic acid. LC-IVIS: tR = 0.94 min; [M+Hr = 556. Example 52 6-Methyl-[mldazo[2,1-b]thiazole-5-carboxyllc acld-(1S,28,5R)-{3-[5-(3,4-difluoro-phenyl)-2-methyl-thlazole-4-carbonyl]-3-aza-blcyclo[3.3.0]oct-2-ylmethyl}-ainlde prepared by reaction of 6-methyl-imidazo[2,1-d]thiazo)e-5-carboxylic acid-[(1 S,2S,5R)-3-a2a-bicyclo[3.3.0]oct-2-ylmethyl]-amide with 5-(3,4-difluoro-phenyi)-2-methyl-thiazoie-4-carboxylicacid. LC-MS: tR = 0.90 min; [M+Hf = 542. Example 53 6-Methyl-lmidazo[2,1 -b]thlazole-5-carboxylic acld-(1 S,2S,5R)-[3-(2-amlno-S-phenyl-thiazole-4-carbonyl)-7-methyl-3-aza-bicyclo[3.3.0]oct-2-yimethyl]-amide prepared by reaction of 6-methyl-imidazo[2,1-d]thlazole-5-carboxylic acid- [(1 S,2S,5R)-7-methyl-3-aza-bicyclo(3.3.0]oct-2-ylmethyl]-amlde with 2-amino-5- phenyi-thiazole-4-carboxylicacid. ' LC-MS: tR = 0.84 min; [jy/l+HJ* = 521. Example 54 6«Methyl-lmldazo[2,1-b]thlazole-5-carboxyllc acid-(1S,2S.5R)-[3-(blph9nyl-2-carbonyl)-7-methyl-3-aza-blcyclo[3.3.0]oct-2-ylmethyl]-amlde prepared by reaction of 6-methyl-lmidazo[2,1-b]thiazole-5-carboxylic acid-[(1S,2S,5R)-7-methyl-3-aza-bicyclo[3.3.0]oct-2-ylmethyl]-amide with commerciaily available biphenyl-2-carboxylic acid. LC-I\^S: tn = 0.96 and 1.01 min; [M+H]* = 499. Example 55 6-Methyl-imidazo[2,1-t>]thlazole-5-carboxyilc acid-(1S,2S,5R)-[7-methyl-3-(3'-methyl-biphenyl-2-carbonyl)-3-aza-btcyclo[3.3.0]oct-2-ylmethyl]-amide prepared by reaction of 6-methyl-imidazo[2,1-d]thiazole-5-ckrboxylip acid-[(1S,2S,5R)-7-methyl-3-aza-blcycloI3.3.0]oct-2-ylmethyl]-amide with commercially available 3'-methyl-biphenyl-2-carboxyllc acid. LC-MS: tR = 0.98 and 1.04 min; [M+Hr = 512. Example 56 6-Methyi-lmidazo[2,1-l)]thiazote-5-carboxyllc acld-(1S,2S,5R)-[7-methyl-3-(4'-mbihyl-blphenyl-2-carbonyl)-3-aza-blcyclo[3.3.0]oct-2-ylmethyl]-amlde prepared by reaction of 6-methyl-imldazo[2,1-d]tiilazole-5-carboxyllc acid-til S,2S,5R)-7-methyl-3-aza-bicyclo[3.3.0]oct-2-ylmethyl]-amlde with commercially available 4'-methyl-biphenyl-2-carboxylic add. LC-MS: tfi = 0.99 and 1.05 mIn; [M+Hr = 512. Examples? 6-Methyl-lmidazo[2,1 -d]thlazole-5-carboxyllc acid-(1 S,2S,5R)-[7-methyl-3-(4'-fluoro-blphenyl-2-carbonyl)-3-aza-blcyclo[3.3.0]oct-2-yimethyl]-amide prepared by reaction of 6-methyl-imidazo[2,1-6]thlazole-5-carboxyllc acid-til S,2S,5R)-7-methyl-3-aza-bicyclo[3.3.0]oct-2-ylmethyl]-amlde with commercially available 4'-fluoro-biphenyl-2-carboxylic acid. LC-MS: tR = 0.96 and 1.01 min; [M+H],' = 517. ' Example 58 6-Methyl-lmldazo[2,1-d]thlazole-5-carboxyllc acld-(1 S,2S,5R)-[7-methyl-3-(3'-methoxy-blphenyl-2-carbonyl)-3-aza-blcyclo[3.3.0]oct-2-ylmethyl]-amide prepared by reaction of 6-methyl-lmidazo[2,1-b]thlazole-5-carboxyllc acid-1(1 S,2S,5R)-7-methyl-3-aza-blcyclo[3.3.0]oct-2-ylmethyl]-amide with commercially available 3'-methoxy-biphenyl-2-carboxylic acid. LC-MS: tR = 0.95 and 1.01 min; [M+H]' = 529. Example 59 6-Methyl-lmidazo[2.1 -d]thiazole-5-carboxyllc acid-(1 S,2S,5R)-[7-methyi-3-(4'-chloro-biphenyl-2-carbonyl)-3-aza-bicyclo[3.3.0]oct-2-ylmethyl]-amide prepared by reaction of 6-methyl-imidazo[2,1 b]thiazole-5-carboxylic acid- [(1S,2S,5R)-7-methyl-3-aza-bicyclo[3.3.0]oct-2-ylmethyl]-amide with commercially available 4'-chloro-biphenyl-2-carboxylic acid. i i' ; LC-MS: tR =1.00 and 1.05 min; [M+Hf = 533. Example 60 6-Methyl-lmidazo[2,1-/)]thlazole-5-carboxyllc acid-(1S,2S,SR)-[3-(blphenyl-2-carbonyl)-3-aza-blcyclo[3.3.0]oct-2-ylmethyl]-amide prepared by reaction of 6-methyl-imidazo[2,1-d]thiazole-5-carbK)xylic acid-[(1S,2S,5R)-3-aza-bicyclo[3.3.0]oct-2-ylmethyl]-amide with commercially available biphenyl-2-carboxylic acid. LC-IVIS: tR = 0.94 min; [M+Hf = 485. Example 61 6-Methyl-lmldazo[2,1-/>]thlazole-5-carboxyllc acld-(1S,2S,5R)-[3-(4'-fluoro- blphenyl-2-carbonyl)-3-aza-blcyclo[3.3.0]oct-2-ylmethyl]-amlde prepared by reaction of 6-methyl-imidazo[2,1-Jb]thiazole-5-carboxylic acid-[(1 S,2S,5R)-3-aza-bicyclo[3.3.0]oct-2-ylmethyl]-amide with commercially available 4'-fluoro-biphenyl-2-carboxylic acid. LC-MS: tR = 0.94 min; [i^+Hf = 485. Example 62 6-Methyl-imldazo[2,1-d]thiazole-5-carboxyllc acid-(1 S,2S,^R)-[3-(3'-methyl-biphenyl-2-carbonyl)-3-aza-bicyclo[3.3.0]oct-2-ylmethyl]-amlde prepared by reaction of 6-methyl-imidazo[2,1-6]thiazole-5-carboxylic acid-[(1S,2S,5R)-3-aza-bicyclo(3.3.0]oct-2-ylmethyl]-amide with commercially available 3'-methyl-biphenyl-2-carboxylicacid. LC-MS: tR = 0.97 min.; [M+H]* = 499. Example 63 6-Methyl-iml(lazo[2,1-Jt>]thiazole-5-carboxyllc acid-(1S,2S,5R)-[3-(3'-methoxy-biphenyl-2-carbonyl)-3-aza-blcyclo[3.3.0]oct-2-yimethyi]-amide prepared by reaction of 6-methyl-imidazo[2,1-6]thiazole-5-carboxylic acid- [(1S,2S,5R)-3-aza-bicyclo[3.3.0]oct-2-ylmethyl]-amide with commercially available 3'- methoxy-biphenyl-2-carboxyllcacid. i LC-IVIS: tR = 0.94 and 1.01 min; [M+H]' = 515. f^' Example 64 6-Methyl-imidazo[2,1 -d]thlazole-5-carboxyllc acid-(1 S,2S,5R)-[3-(2-methyl-5-phenyl-thlazole-4-carbonyl)-3-aza-blcyclo[3.3.0]oct-2-ylinethyi]-amlde prepared by reaction of 6-methyl-imldazoI2,1-£)]thlazole-5-carboxyllc acid-[(1S,2S,5R)-3-aza-bicyclo[3.3.0]oct-2-ylmethyl]-amide with commercially available 2-methyl-5-phenyl-thiazole-4-carboxylicacid. LC-MS: tR = 0.88 min; [M+H]" = 506. Example 65 6-Methyl-imidazo[2,1 -d]thiazole-5-carboxyllc acld-(1 S,2S,5RH3^[5-(4-fluoro-phenyl)-2-methyl-thiazole-4-carbonyl]-3-aza-blcyclo[3.3.0)oct-2-ylmethyl}-amide prepared by reaction of 6-methyl-imidazo[2,1-b]thiazole-5-carboxylic acid-[(1 S,2S,5R)-3-aza-bicyclo[3.3.0]oct-2-yimethyl]-amide with 5-(4-fluoro-pheniyl)-2-methyl-thiazole-4-carboxylic acid. LC-MS: tR = 0.89 min; [M+H]' = 524. Example 66 6-Methyl-lmidazo[2.1-d]thiazole-5-carboxylic acid-(1S,2S.^R)-{3-[5-(4-ethyl-phenyl)-2-methyl-thlazoie-4-carbonyl]-3-aza-blcyclo[3.3.0]oct-2-ylmettiyl}-amlde prepared by reaction of 6-methyl-imidazo[2,1-b]thiazole-5-carboxylic acid-[(1 S,2S,5R)-3-aza-bicyclo[3.3.O]oct-2-ylm0thyl]-amide with 5-(4-ethyl-phenyl)-2-methyl-thiazole-4-carboxylicacid. LC-MS: tR = 0.95 min; [M+Hl* = 534. Example 67 6-Methyl-lmidazo[2,1-b]thlazole-5-carboxyllc acid-(1S,2S,5R)-{3-[5-(4-chioro-phenyl)-2-methyl-thiazole-4-carbonyl]-3-aza-blcyclo[3.3.0]oct-2-ytmethyl}-amlole prepared by reaction of 6-methyl-imidazo[2,1-(f)lthiazole'5-carboxylic acid-[(1S,2S,5R)-3-aza-bicyclo[3.3.0]oct-2-ylmethyl]-amide with 5-(4-chloro-phenyl)-2-methyl-thiazole-4-carboxylicacid. LC-MS: tR = 0.92 min; [l\/1+Hr = 540. i Example 68 / 6-Methyl-imldazo[2,1-()lthiazole-5-carboxyllc acid-(1S,2S.SRH3-[2-methyl-5-(4-trlfluoromethyl-phenyl)-thlazole^4-carbonyl]-3-aza-blcyclo[3.3.0]oct-2-ylmethyl}-amlde prepared by reaction of 6-methyl-imidazo[2,1-b]thiazole-5-carboxylic acid- [(1S,2S,5R)-3-aza-bicyclo[3.3.0]oct-2-ylmethyi]-amide witii 2-metliyl-5-(4- trifluorometliyl-plienyl)-thiazole-4-carboxyiic acid. LC-I\/IS: tR = 0.95 min; [M+H]' = 574. Example 69 6-Methyl-lmldazo[2,1-b]thlazole-5-carboxyllc acld-(1S,2S,5R)-{3-[2-amlno-5-(3-methyl-phenyl)-thlazole-4-carbonyl]-3-aza-blcyclo[3.3.0]oct-2-yimethyl}-amide prepared by reaction of 6-metliyl-lmidazo[2,1-5]thiazole-5-carboxylic acid-[(1 S,2S,5R)-3-aza-bicyclo[3.3.0]oct-2-yimethyl]-amide with 2-amino-5-(3-methyl-phenyl)-thiazole-4-carboxylicacid. LC MS: tR = 0.83 min; [M+HK = 521. Example 70 6-Methyl-lmldazo[2,1 -d]thiazole-5-carboxyllc acld-(1 S,2S,5R)-{3-[2-amino^-(3-fluoro-phenyl)-thiazole-4-carbonyl]-3-aza-blcyclo[3.3.0]oct-2-ylmethylV|amide prepared by reaction of 6-methyt-imidazo[2,1-t)]thiazole-5-carboxyli6 acid-[(1 S,2S,5R)-3-aza-bicyclo[3.3.01oct-2-ylmethyl]-amide with 2-amino-5-(3-fluDro-phenyl)-thiazole-4-carboxylicacid. LC-MS: tR = 0.82 min; [M+Hr = 525. Example 71 6-Mdthyr-lmidazo[2.1-l)]thlazole-5-carboxyllc acid-(lS,2S,5R)-[3-(2-amlno-5-phenyf-thlazole-4-carbonyl)-3-aza-blcyclo[3.3.0]oct-2-ylmethyl]-amide prepared by reaction of 6-methyl-imidazo[2,1-d]thiazole-5-carboxylic acid-[(1S,2S,5R)-7-methyl-3-aza-bicyclo[3.3.0Joct-2-ylmethyl]-amide with 2-amino-5-phenyl-thiazole-4-carboxylicacid. LC-MS: tR = 0.80 mln; {M+Hr = 507. Example 72 6-Methyl-lmldazo[2,1-l)]thiazole-5-carboxyllc acld-(1S,2S,5R)-{7-me^yl-3-[2- amlno-5-(3-methyl-phenylHhiazole-4-carbonyl]-3-aza-bicyclo[3.3.0]oct-2- ylmethyl}-amlde prepared by reaction of 6'metliyl-imidazo[2,1-b]thiazole-5-carboxylic acid-[(1S,2S,5R)-7-methyl-3-aza-bic^lo[3.3.0]oct-2-ylmetliyf|-amide witii 2-amino-5-(3-metliyl-phenyl)-tliiazole-4-carboxylicacid. LG-MS: tR = 0.86 min; [M+Hr = 535. Example 73 6-Methyl-imldazo[2,14)]thiazole-5-carboxylic acld-(18,28,5R)-{7-methyf-^[2- amlno-S-(4-fluoro-phenyl)-thlazoie-4-carbonyl]-3-aza-bicyclo[3.3.0}oct-2- ylmethyl}-amide prepared by reaction of 6-methyl-lmidazo[2,1-fc]thiazole-5-carboxylic acid-[(1S,2S,5R)-3-aza-bicycloI3.3.0]oct-2-ylmethyl]-amlde with 2-amino-5-(4-fluoro-phenyl)-thiazole-4-carboxylicacid. LC-MS: tR = 0.85 min; [M+H]* = 539. Example 74 6-Methyl-lmldazo[2,1-d]thlazole-5-carboxylic acld-(1S4i8,5R)-{7-meth^-3-[2- amlno-5-(3-fluoro-phenyl)-thlazole-4-carbonyl]-3-aza-blcyclo[3.3.0]oct-2- ylmethyl}«amlde ', prepared by reaction of 6-metliyl-imidazo[2,1-fe]thiazole-5-carboxylic acid-[(1S,2S,5R)-3-aza-bicyclo[3.3.0loct-2-ylmethyQ-amide with 2-amino-5-(3-fluoro-phenyl)-thiazoie-4-carboxylicacid. LC-MS: tR = 0.86 min; [M+HK = 539. Example 75 lmfdazoC2,l-d]thiazole-6-carboxylic acid-(1S,2S,5R)-[3-(2-niethyl-5-m-tolyi- thiazole-4-carbonyl)-3-aza-bicyclo[3.3.0]oct-2-ylmethyl]-amide prepared by reaction of imldazo[2,1-i!)]thiazole-6-carboxylic acid-[(1 S,2S,5R)-3-aza-bicyclo[3.3.0]oct-2-ylmethyl]-amide with 2-methyl-5-/77-tolyl-thlazole-4-carboxylic acid. LC-MS: tR = 0.95 min; [M+Hr = 506. Preparation of Examples (general procedure II) The compound of the following example has been prepared using general procedure II described above. Example76 •■ ' ' (1S,2S,5R)-2-Methyl-A/-[7-Methyl-3-(2-methyl-5^-tolyl-thiazole-4-carbonyl)>3-aza-bicyclo[3.3.0]oct-2-ylmethyl]-lsonlcotlnamlde prepared by reaction of [(1S,2S,5R)-2-aminomethyl-7-methyl-3-aza-blcyclo[3.3.0]oct-3-yl]-(2-methyl-5-/n-tolyl-thiazol-4-yl)-methanone with 2-methyl-isonicotinic add. LC-MS: tR = 0.90 min; [M+Hr = 489. Example 77 2-Methyl-benzofuran-4-carboxyllc acld-(1S,2S,5R)- [7,7-difluoro-3-(2-methyl-5-m-tolyl-thlazole-4-carbonyi)-3-aza-blcyclo[3.3.0]oct-3-yimethyl]-amlde prepared by reaction of (1 S,2S,5R)-(2-aminomethyl-7,7-dlfluorO'3-aza-blcyclo[3.3.0]-oct-3-yl)-(2-methyl-5-m-tolyl-thiazol-4-yl)-methanone with 2-methyl-benzofuran-4-carboxylic acid (prepared according to scheme 15). LC-MS: tp = 1.05 min; [M+Hf = 550.09 Example 78 3-Methyl-benzofuran-4-carboxyllc acld-(1S,2S,5R)- [7,7-difluoro-3'(2»methyl-5' m-tolyl-thlazoie-4-carbonyl)-3-aza-blcyclo[3.3.0]oct-3-ylmethyl]-amide prepared by reaction of (1S,2S,5R)-(2-aminomethyl-i7,7-difluoro-3-aza-bicyqlo[3.3.0]-oct-3-yl)-(2-methyl-5-/T7-tolyl-thiazol-4-yl)-methanonq, with 3-methyl-berizofuran-4-carboxylic acid (prepared according to scheme 14). LC-MS: tR = 1.03 min; [M+Hr = 550.05 Example 79 2,3-Dlhydro-benzofuran-4-carboxyllc acld-(1 S,2S,5R)-[7,7-dlfluoro-3-(2-methyl-5-m-tolyl-thiazole-4-carbonyl)-3-aza-bicyclo[3.3.0]oct-2-ylmethyl]-amide prepared by reaction of (1 S,2S,5R)-(2-aminomethyl-7,7-difluoro-3-aza-bicyclo[3.3.0]-oct-3-yl)-(2-methyl-5-m-tolyl-thiazol-4-yl)-methanone with 2,3-dihydro-benzofuran-4-carboxylic acid. LC-MS: tR = 1.01 min; [IVI+H]' = 537.99 Example 80 2,3-Dihydro-benzo[1,4]dloxlne-5-carboxyllc acld-(1 S,2S,5R)-[7,7-dif luoro-3-(2-methyl-5-m-tolyl-thiazole-4-carbonyl)-3-aza-blcyclb[3.3.0]oct-2-ylmethyl]-amlde prepared by reaction of (1S,2S,5R)-(2-aminomethyl-7,7-difluoro-3-aza-bicyclp[3.3.0]- oct-3-yl)-(2-metliyl-5-m-tolyl-thiazol-4-yl)-methanone witli 2,3-dihydro- benzo[1,4]dioxine-5-carboxylic acid. LC-MS: tfi = 1.00 min; [IVI+Hr = 553.97 Example 81 Benzothiazole-7-carboxyllc acid-(1S,2S,5R)-[7,7-difluoro-3-(2-methyl-5-m-tolyl-thlazole-4-carbonyl)-3-aza-blcyclo[3.3.0]oct-2-yimethyl]-amlde prepared by reaction of (1S,2S,5R)-(2-aminomethyl-7,7-difluoro-3-aza-bicyclo[3.3.0]-oct-3-yl)-(2-methyl-5-m-tolyl-thiazol-4-yl)-methanone with benzothiazole-7-carboxylic acid (prepared according to scheme 13). LC-IVIS: tR = 1.02 min; [M+H]^ = 553.07 Example 82 6-Methyl-pyrroio[2,1 -l7]thiazole-7-carboxyllc acld-(1 S,2S,5R)-[7,7-difiuoro-3-(2-methyl-5-m-tolyl-thlazole-4-carbonyl)-3-aza-blcyclo[3.3.0]oct-2-ylmethyl]-amide prepared by reaction of (1S,2S,5R)-(2-aminomethyl-7,7-dlfluoro-3-aza-bicyclo[3.3.0]-oct-3-yl)-(2-methyl-5-/TJ-tolyl-thlazol-4-yl)-methanone with 6-methyl-pyrrolol2,1-b]thiazole-7-carboxyllc acid (prepared according to scheme 12). LC-MS: tR = 0.99 min; [M+H]' = 554.86 Example 83 lmidazo[1,2-a]pyridine-3-carboxylic acid-<1 S,2S,5R)-[7,7-difiuoro-3-(2-methyl-5-m-toiyl-thiazole-4-carbonyt)-3-aza-blcyclo[3.3.0]oct-2-ylmethyl]-amide prepared by reaction of (1S,2S,5R)-(2-aminomethyl-7,7-dlfluoro-3-aza-bicyclop.3.0]-oct-3-yl)-(2-methyl-5-m-tolyl-thia2ol-4-yl)-methanone with imldazo{1,2na]pyrid}ne-3-carboxyllc acid. LC-MS: tR = 0.89 min; [IVI+Hr = 536.06 Example 84 1 -Methyl-1 H-lndazole-3-carboxyllc acid-(1 S,2S,5R)-rr,7-dlfluoro-3-(2-methyl-5-m-tolyl-thlazole-4-carbonyl)-3-aza-blcyclo[3.3.0]oct-2-ylmethyl]-amlde prepared by reaction of (1S,2S,5R)-(2-aminomethyl-7,7-dlfluoro-3-aza-bicyclo[3.3.0]-oct-3-yl)-(2-methyl-5-m-tolyl-thiazol-4-yl)-methanone with 1-methyl-1H-inda2ole-3-carboxylic acid. LC-MS: tR = 1.02 min; [M+HY = 550.12 Example 85 6-Methyl-lmidazo[2,1^]-thiazole-5-carboxylic acld-(lS,2S.5R)-[7,7-dlfluoro-3-(2-methyl-5-m-tolyf-thlazole-4-carbonyl)-3-aza-blcyclo[3.3.0]oct2-ylmethyl]-amide prepared by reaction of (1S,2S,5R)-(2-aminomethyi-7,7-difluoro-3-aza-bicyclo[3.3.0]-oct-3-yl)-(2-methyl-5-m-tolyl-thiazol-4-yl)-methanone with 6-methyl-imidazo{2,1-£)]thiazole-5-carboxylic acid. LC-MS: tR = 0.89 min; [M+H]' = 556.04 II. Biological assays In vitro assay The orexin receptor antagonistic activity of the compounds of formula (I) is determined in accordance with the following experimental method. Intracellular calcium measurements: Chinese hamster ovary (CHO) cells expressing the human orexln-1 receptor and the human orexin-2 receptor, respectively, are grown in culture medium (Ham F-12 with L-Glutamine) containing 300 |ag/ml G418,100 U/ml penicillin, 100 ng/ml streptomycin and 10 % heat inactivated fetal calf serum (PCS). The cells are seeded at 20'000 .1 cells / well into 384-well black clear bottom sterile plates (Greiner). The seeded plates are incubated overnight at Sy'C in 5% CO2. Human orexin-A as an agonist is prepared as 1 mM stock solution in MeOH: water (1:1), diluted in HBSS containing 0.1 % bovine serum albumin (BSA), NaHCOa: 0.375g/l and 20 mM HEPES for use in the assay at a final concentration of 3 nM. Antagonists are prepared as 10 mM stock solution in DMSO, then diluted in 384-well plates using DMSO followed by a transfer of the dilutions into In HBSS containing 0.1 % bovine serum albumin (BSA), NaHCOa: 0.375g/l and 20 mM HEPES. On the day of the assay, 50 ^1 of staining buffer (HBSS containing 1% PCS, 20 mM HEPES, NaHCOa: 0.375g/l, 5 mM probenecid (Sigma) and 3 \iM of the fluorescent calcium indicator fluo-4 AM (1 mM stock solution in DMSO, containing 10% pluronic) is added to each well. The 384-well cell-plates are incubated for 50 min at 37" C in 5% COz followed by equilibration at rt for 30 -120 min before measurement. Within the Fluorescent Imaging Plate Reader (FLIPR2 or FLIPR Tetra, Molecular Devices), antagonists are added to the plate in a volume of 10 ^I/well, incubated for 10 min and finally 10 |il/well of agonist is added. Fluorescence is measured for each well at 1 second intervals, and the height of each fluorescence peak is compared to the height of the fluorescence peak induced by 3 nM orexin-A with vehtele in place of antagonist. For each antagonist, the IC50 value (the concentration of compound needed to inhibit 50 % of the agonistic response) is detennlned. With the FLIPR Tetra, non-optimized and optimized conditions were used. Optimized conditions were achieved by adjustment of pipetting speed and cell; splitting regime. The calculated ICso values of the compounds may fluctuate depending on the daily cellular assay performance. Fluctuations of this kind are known to those skilled in the art. ■I Antagonistic activities (IC50 values) of all exemplified compounds are in the range of 2-1640 nM with respect to the OX1 receptor and in the range of 3-2516 nM with respect to the OX2 receptor. Antagonistic activities of selected compounds are displayed in Table 1. ' Claims 1. A compound of the formula (I) wherein R2-represents hydrogen,■(C1-4)alkyl or fluorine; R2 represents hydrogen, (C1-4)alkyl or fluorine; R2 represents aryl, which is unsubstituted, mono-, di-, or tri-substituted, wherein the substituents are independently selected from the group consisting of (C1-4)alkyl, (C1-4)alkoxy, trifluoromethyl, trifluoromethoxy, and halogen; or heteroaryl, which is unsubstituted, mono-, di-,sor tri-substltuted, wherein the substituents are independently selected from the group consisting of (C1-4)alkyl, (CM)alkoxy, halogen, and trifluoromethyl; A represents R" represents (Ci,,)alkyl, or-NR2R2 R2 represents (C1-4)alkyl; R® represents hydrogen, or (C1-4)alkyl; R' represents hydrogen, or (C1-4)alkyl; and D represents aryl, which is unsubstituted, mono-, di-, or trI-substituted, wherein the substituents are independently selected from the group consisting of (C1-4)alkyl, (C1-4)alkoxy, trifluoromethyl, and halogen.; or a salt of such a compound. 2. A compound of formula (I) according to claim 1, wherein R2 represents hydrogen, or (C1-4)alkyl; and R2 represents hydrogen, or (C1-4)alkyl; or a salt of such a compound. 3. A compound of formula (I) according to claim 1 or 2, wherein A represents 4. A compound of fomula (I) according to any one of claims 1 to 3, wherein R* represents methyl, or -NHg; or a salt of such a compound. 5. A compound according to any one of claims 1 to 4, wherein D represents phenyl, which is unsubstituted, mono-, di-, or tri-substituted, wherein the substituents are independently selected fi*om the group consisting of (C1-4)alkyl, (C1-4)alkoxy, trifiuoromethyl, and halogen; or a salt of such a compound. 6. A compound according to any one of claims 1 to 5, wherein R2 represents phenyl, which is unsubstituted, mono-, di-, or tri-substituted, wherein the substituents are independently selected from the group consisting of (C1-4)alkyl, (C1-4)alkoxy, trifiuoromethyl, trifluoromethoxy, and halogen; 2,3-dihydro-benzofuranyl; benzo[1,3]dioxolyl; 2,3-dihydro-benzo[1,4]dioxlnyl; 4H-benzo[1,3]diQxinyl; or an isoxazolyl, a pyridyl, an indazolyl, a benzofuranyl, a benzoxazolyl, a benzisdxazolyl, a benzolsothiazolyl, or an imidazo[2,1-b]thiazolyl group, wherein said groups are unsubstituted, mono-, di-, or tri-substituted, wherein the substituents are independently selected from the group consisting of j[C1-4)alkyl, (C1-4)alkoxy; halogen, and trifiuoromethyl; ij p or a salt of such a compound. ^ . 7. A compound according to any one of claims 1 to 6 selected from the group consisting of: 2,3-Dihydro-benzoI1,4]dloxine-5-carboxylic acid-(1 S,2S,5R)-[3-(2-methyl-5-m-tolyl-thia;?ole-4-carbonyl)-3-aza-bicyclo[3.3.0]oct-2-ylmethyl]-amide; Benzo[d]isothiazole-3-carboxylic acid-(1S,2S,5R)-[3-(2-methyl-5-m-tolyl-thiazote-4-carbonyi)-3-aza-biqyclo[3.3.0]oct-2-ylmethyl]-amkle; (1S,2S,5R)-3-Bromo-/S/-[7-methyl-3-(2-methyl-5-m-tolyl-thiazole-4-carbonyl)-3-aza- bicyclo[3.3.0]oct-2-ylmethyl]-benzaniicle; (1S,2S,5R)-3-Chloro-/S/-I7-methyl-3-(2-methyl-5-m-tolyl-thlazole-4-carbonyl)-3-aza- bicyclo[3.3.0]oct-2-ylmethyl]-benzamide; (1 S,2S,5R)-3-Fluoro-/V-[7-methyl-3-(2-methyl-5-m-tolyl-thiazole-4-carbonyl)-3-aza- bicyclo[3.3.0]oct-2-ylmethyl]-benzamide; (1S,2S.5R)-3-Methoxy-/V-[7-methyl-3-(2-methyl-5-/T7-tolyl-thiazole-4-carbonyl)-3-aza- bicyclo[3.3.0]oct-2-ylmethyr|-benzamicle; , (1S,2S,5R)-/V-[7-methyl-3-(2-methyl-5-m-tolyl-thlazol©r4-carbonyl)-3-aza- bicyclo[3.3.O]oct-2-ylmethyl]-3-trifluorom0thyl-benzamicle; (1S,2S,5R)-3-Methyl-A/-{7-methyl-3-(2-methyl-5-m-tolyl-thiazole-4-carbonyl)iS-aza- bicyclo[3.3.0]oct-2-ylmethyl]-benzamide; (1S,2S,5R)-A/-[7-methyl-3-(2-methyl-5-m-tolyl-thiazole-4-carbonyl)-3-aza- bicyclo[3.3.0]oct-2-ylmethyl]-3-trifluoromethoxy-benzamide; 6-Trifluoromethyl-pyridine-2-carboxyllc acid-(1S,2S,5R)-[7-methyl-3-(2-methyl-5-m- tolyl-thiazole-4-carbonyl)-3-aza-bicyclo[3.3.0]oct-2-ylmethyll-amlde; 6-Methoxy-pyridine-2-carboxylic acid-(1S,2S,5fl)-{7-methyl-3-(2-methyl-5-/77-tolyl- thiazole-4-carbonyl)-3-aza-blcyclo[3.3.0]oct-2-ylmethyl]-amide; 4-Bromo-pyridine-2-carboxylic acld-(1 S,2S,5R)-[7-methyl-3-(2-methyl-5-/r7-tolyl- thia2ole-4-carbonyl)-3-aza-bicyclo[3.3.0]oct-2-ylmethyl]-amide; 4-Chloro-pyridine-2-carboxylicacid-(1S,2S,5R)-[7-methyl-3-(2-methyl-5-/n-tolyl- thiazole-4-carbonyl)-3-aza-bicyclo[3.3.0]oct-2-ylmethyl]-amide; 4-Methyl-pyridine-2-carboxylic acid-(1S,2S,5R)-[7-methyl-3-(2-methyl-5-m-tolyl- thiazole-4-carbonyl)-3-aza-bicyclo[3.3.0]oct-2-ylmethyl]-amide; (1S,2S,5R)-5-Bromo-W-[7-methyl-3-(2-methyl-5-m-tolyl-thiazole-4-carbonyl)-3-aza- bicyclo[3.3.0]oct-2-ylmethyl]-nicotinamide; (1 S,2S,5R)-5-Chloro-A/-I7-methyl-3-(2-methyl-5-m-tolyl-thlazole-4-carbonyl)-3-aza- bicyclo[3.3.0]oct-2-ylmethyl]-nicotinamide; (1S,2S,5R)-5-Methyl-N-(7-methyl-3-(2-methyl-5-m-tbiyl-thiazole-4-carbonyiy-3-aza- bicyclo[3.3.0]oct-2-ylmethyl]-nicotinamide; Benzofuran-4-carboxylic acid-(1 S,2S,5R)-[7-methyl-^-(2-methyl-5-m-tolyl-th|azole-4- carbonyl)-3-aza-bicyclo[3.3.0]oct-2-ylmethyl]-amide; 2-Methyl-benzofuran-4-carboxylic acid-(1S,2S,5R)-[7-methyl-3-(2-methyl-5-m-tolyl- thiazole-4-carbonyl)-3-aza-bicycloI3.3.0]oct-2-ylmethyl]-amlde; 2-Methyl-benzoxazole-4-carboxylicacid-(1S,2S,5R)-[7-methyl-3-(2-methyl-5-m-tolyl- thiazole-4-carbonyl)-3-aza-bicyclo[3.3.0]oct-2-ylmethyl]-amide; 2,3-Dihydro-ben2oI1,4]dioxine-5-carboxylic acid-(1 S,2S,5R)-r7-methyl-3-(2-methyl-5- m-tolyl-thiazole-4-carbonyl)-3-aza-bicyclo[3.3.0]oct-2-ylmethyl]-amide; 1 -Methyl-indazole-3-carboxylic acid-(1 S,2S,5R)-[7-methyl-3-(2-methyl-5-/T7-tolyl- thiazole-4-carbonyl)-3-aza-bicyclo[3.3.0]oct-2-ylmethyl]-amide; 3,5-Dimethyl-isoxazole-4-carboxylicacid-(1S,2S,5R)-I7-methyl-3-(2-methyl-5-/n-tolyl- thiazole-4-carbonyl)-3-aza-bicyclo[3.3.0]oict-2-ylmethyl]-amide; Benzo[d]isoxazole-3-carboxylic acid-(1 S,2S,5R)-[7-methyh3-(2-methyl-5-m-tolyl- thiazole-4-carbonyl)-3-aza-bicyclo[3.3.0]oct-2-ylmethyi]-amide; (1S,2S,5R)-2-Methyl-A/-[7-methyl-3-(2-methyl-5-/n-toiyl-thiazole-4-carbonyl)-3-aza- bicyclo[3.3.0]oct-2-ylmethyl]-isonicotinamide; l! Benzo[c/]isoxazole-3-carboxylic acid-(1 S,2S,5R)-[3-(^imethyl-5-/TJ-tolyl-thiazote-4- carbonyl)-3-aza-bicyclo[3.3.0]oct-2-ylmethyl]-amide; I j Benzo[d]isothiazole-3-carboxylicacid-(1S,2S,5R)-[7-ttiethyl-3-(2-methyl-5-n1-t6lyi- thiazole-4-carbonyl)-3-aza-bicyclo[3.3.0]oct-2-ylmethyl]-amlde; lmidazo[2,1 -d]thiazole-5-carboxylic acid-(1 S,2S,5R)-[7-methyl-3-(2-methyl-5-/TJ-tolyl- thiazole-4-carbonyl)-3-aza-bicyclo[3.3.0]oct-2-ylmethyl]-amide; lmidazo[2,1 -/)]thiazole-5-carboxylic acid-(1 S,2S,5R)-[3-(2-methyl-5-m-tolyl-thiazole-4- carbonyl)-3-aza-bicyclo[3.3.0]oct-2-ylmethyl]-amide; lmidazo[2,1 -b]thiazole-6-carboxylic acid-(1 S,2S,5R)-[7-methyl-3-(2-methyl-5-m-tolyl- thiazole-4-carbonyl)-3-aza-bicyclo[3.3.0]oct-2-ylmethyl]-amide; 6-Methyl-imidazo[2,1 -b]thiazole-5-carboxylic acid-(1 S,2S,5R)-[3-(2-methyl-5-m-tolyl- thiazole-4-carbonyl)-3-aza-bicyclo[3.3,0]oct-2-ylmethyl]-amide; 6-Methyl-pyridine-2-carboxylic acid-(1 S,2S,5R)-[7-methyl-3-(2-methyl-5-n7-tolyl- thiazole-4-carbonyl)-3-aza-bicyclo[3.3.0]oct-2-ylmethyl]-amide; 6-Methyl-imidazo[2,1 -b]thia2ole-5-carboxylic acid-(1 S,2S,5R)-[7-methyl-3-(2-methyl- 5-m-tolyl-thiazole-4-carbonyl)-3-aza-bicyclo[3.3.0]oct-2-ylmethyl]-amide; 6-Methyl-imidazo[2,1 -/b]thiazole-5-carboxylic acid-(1 S,2S,5R)-{3-[5-(3-m0thoxy- phenyl)-2-methyl-thlazole-4-carbonyl]-3-aza-bicyclo[3.3.0]oct-2-ylmethyl}-amide; 6-Methyl-imidazo[2,1 -d]thiazole-5-carboxylic acid-(1 S,2S,5R)-{3-[5-(3-methoxy- phenyl)-2-methyl-thiazole-4-carbonyl]-7-methyl-3-a24-bicyclo[3.3.0Joct-2-ylmethy^ amide; | 6-Methyl-imidazo[2,1 -/)]thiazole-5-carboxylic acid-(1 S,2S,5R)-{3-[2-rnethyl-^-(3- trifluoromethyl-phenyl)-thiazole-4-carbonyl]-3-aza-bicyclol3.3.0]oct-2-ylmethy^- amide; 6-Methyl-imidazo[2,1-b]thiazole-5-carboxylic acid-(1S,2S,5R)-{7-methyl-3-[2-methyl- 5-(3-trifluoromethyl-phenyl)-thiazole-4-carbonyl]-3-aza-bicyclo[3.3.0]oct-2-ylmethyl}- amide; 6-Methyl-imidazo[2,1 -£)]thia2ole-5-carboxylic acid-(1 S,2S,5R)-{3-[5-(3-fluoro-phenyl)- 2-methyl-thiazole-4-carbonyl]-3-aza-bicyclo[3.3.0]oct-2-ylmethyf)^-amide; 6-Methyl-imidazo[2,1-d]thlazole-5-carboxylic acid-(1 S,2S,5R)-{3-[5-(3-fluoro-phenyl)- 2-methyl-thiazole-4-carbonyl]-7-methyl-3-aza-bicyclo[3.3.0]oct-2-ylmethyl}-amide; 6-Methyl-imidazo[2,1 -d]thiazole-5-carboxylic acid-(1 S,2S,5R)-[7-methyl-3-(2'methyl- 5ptolyl-thiazole-4-carbonyl)-3-aza-blcyclo[3.3.0]oct-J?-ylmethyl]-amlde; 6-Methyl-imidazo[2,1-b]thlazole-5-carboxylic acid-(1 S,2S,5R)-[3-(2-methyl-5-p-tolyl- thiazole-4-carbonyl)-3-aza-bicyclo[3.3.0]oct-2-ylmethyl]-amide; 6-Methyl-imidazo[2,1-6]thiazole-5-carboxyllc acid-(lSJ2S,5R)-{3-[5-(3-chloro-phenyl)- 2-methyl-thiazole-4-carbonyl]-3-aza-bicyclof3.3.0]oct-':^-ylmethy^amide; 6-Methyl-imidazo[2,1 -b]thiazole-5-carboxyllc acid-(1 S,2S,5R)-{3-[5-(3-chloro-Rhenyl)- 2-methyl-thiazole-4-carbonyl]-7-methyl-3-aza-bicyclo[3.3.0]oct-2-ylmethyl}-amide; 6-Methyl-imidazo[2,1-i)]thiazole-5-carboxylic acid-(1 S,2S,5R)-{3-{5-(4-methoxy- phenyl)-2-methyl-thiazole-4-carbonyq-3-aza-bicyclo[3.3.0]oct-2-ylmethyl}-amide; 6-Methyl-imidazo[2,1-b]thiazole-5-carboxylic acid-(1S,2S,5R)-{3-[5-(4-methoxy- phenyl)-2-methyl-thiazole-4-carbonyl]-7-methyl-3-aza-bicyclo[3.3.0]oct-2-ylmethyl}- amide; 6-Methyl-imidazo[2,1-b]thiazole-5-carboxylic acid-(1 S,2S,5R)-{3-[5-(4-ethyl-pHenyl)- 2-methyl-thiazole-4-carbonyl]-7-methyl-3-aza-bicyclo[3.3.0Joct-2-ylmethyl}-amide; 6-Methyl-imidazo[2,1-b]thiazole-5-carboxylic acid-(1 S,2S,5R)-{7-methyl-3-[2-methyl- 5-(4-trifluoromethyl-phenyl)-thlazole-4-carbonyl]-3-aza-bicyclot3.3.0]oct-2-ylmethyiy- amide; 6-Methyl-imldazo[2,1 -ij]thiazole-5-carboxylic acld-(1 S,2S,5R)43-l5-(4-fluoro-phenyl)- 2-methyl-thiazole-4-carbonyl]-7-methyl-3-aza-bicyclo[3.3.0]oct-2-ylmethyl}-amide; 6-Methyl-imidazot2,1 -b]-thlazole-5-carboxylic acid-(1 S,2S,5R)-{7-m©thyl-3-[2-mothyl- 5-phenyl-thiazole-4-carbonyl]-3-aza-blcyclo[3.3.0]oct-2-ylmethyl}-amlde; 6-Methyl-imldazo[2,1-b]thiazole-5-carboxylic acid.(1 S,2S,5R)-{3-I5-(3,4-dlmethyl- phenyl)-2-methyl-thiazole-4-carbonyl]-7-methyJ-3-aza-bicyclo[3.3.0]oct-2-ylmethyl}- amide; ' 6-Methyl-imidazo[2,1-to]thiazole-5-carboxylic acld-(13.2S.5R)-{3-[5-(3,4-dlmethyl- phenyl)-2-methyl4hiazole-4-carbonyl]-3-aza-bicyclo[d.3.01oct-2-ylm©thyl}-amide; 6-Methyl-imidazo[2,1-b]thlazole-5-carboxylic acid-(1S,2S.5R)-{3-[5-(3,4-difluoVo- phenyl)-2-methyl-thlazo|e-4-carbonyl]-7-metliyl-3-aza-blcyclo[3.3.0]oct-2-ylmethyl}- amide; 6-Methyl-imiclazo[2,1 -b]thiazole-5-carboxyllc acid-(1 S,2S,5R)-{3-[5-(3,4-difluoro- phenyl)-2-methyl-thiazole-4-carbonyl]-3-aza-bicyclo[3.3.0]oct-2-ylmethyl}-amide; 6-Methyl-imidazo[2,1-il)]thiazole-5-carboxylic acid-(1S,2S,5R)-[3-(2-amino-5-phenyl- thiazole-4-carbonyl)-7-methyl-3-aza-bicyclo[3.3.0]oct-2-ylmethyl]-amide; 6-Methyl-imidazo[2,1-b]thiazole-5-carboxylic acid-(1 S,2S,5R)-[3-(biphenyl-2- carbonyl)-7-methyl-3-aza-bicyclo[3.3.0]oct-2-ylmethyl]-amide; 6-Methyl-imidazo[2,1-b]thiazole-5-carboxylic acid-(1 S,2S,5R)'[7-methyl-3-(3'-methyl- biphenyl-2-carbonyl)-3-aza-bicyclo[3.3.0]oct-2-ylmethyl]-amide; 6-Methyl-imidazo[2,1 -/3]-thlazole-5-carboxylic acid-(1 S,2S,5R)-[7-methyl-3-(4'-methyl- biphenyl-2-carbonyl)-3-aza-bicyclo[3.3.0]oct-2-ylmethyl]-amlde; 6-Methyl-imidazo[2,1-t)J-thiazole-5-carboxylic acid-(1 S,2S,5R)-[7-methyl-3-(4'-fluoro- biphenyl-2-carbonyl)-3-aza-bicyclo[3.3.0]oct-2-ylmethyl]-amlde; 6-Methyl-imidazo[2,1 -d]-thiazole-5-carboxylic acid-(13,2S,5R)-|7-methyl-3-(3'- methoxy-biphenyl-2-carbonyl)-3-aza-bicyclo[3,3.0]oct-t2-ylmethyll-amlde; 6-Methyl-imidazo[2,1 -b]-thiazole-5-carboxylic acid-(1 S,2S,5R)-I7-methyl-3-(4'rchloro- biphenyl-2-carbonyl)-3-aza-bicyclo[3.3.0]oct-2-ylmethyi]-amide; ''' ' 6-Methyl-imidazo[2,1 -b]thlazole-5-carboxylic acid-(1 S,2S,5R)-l3-(blphenyl-2- carbonyl)-3-aza-bicyclo[3.3.0]oct-2-ylmethyl]-amide; 6-Methyl-imidazo[2,1 -b]-thiazole-5-carboxylic acid'(1 S,2S,5R)-l3-(4'-fluoro-blphenyl- 2-carbonyl)-3-aza-bicyclo[3.3.0]oct-2-ylmethyl]-amlde; 6-Methyl-lmidazo[2,1 -b]-thiazole-5-carboxyllc acid-(1 S,2S,5R)-[3-(3'-methyl-biphenyl- 2-carbonyl)-3-aza-bicyclo[3.3.0]oct-2-ylmethylJ-amide; 6-Methyl-imidazo[2,1 -b]-thlazole-5-carboxyllc acid-(1 S,2S,5R)-[3-(3'-methoxy- biphenyl-2-carbonyl)-3-aza-bicyclo[3.3.0]oct-2-ylmethyl]-amlde; 6-Methyl-imidazo[2,1-b]-thiazole-5-carboxylic acid-(1S,2S,5R)-[3-(2-m©thyl-5-phenyl- thiazole-4-carbonyl)-3-aza-bicyclo[3.3.0]oct-2-ylmethyl]-amide; 6-Methyl-imidazo[2,1 -b]thiazole-5-carboxylic acid-(1 S,2S,5R)-{3-[5-(4-fluoro-phenyl)- 2-methyl-thiazole-4-carbonyl]-3-aza-bicyclo[3.3.0]oct-2-ylmethyl}-anilde; 6-Methyl-imldazo[2,1-b]thiazole-5-carboxylicacid-(1S,2S,5R)-{3-[5-(4-ethyl-phenyl)- 2-methyl-thiazole-4-carbonyl]-3-aza-bicyclo[3.3.0]oct-2-ylmethyl}-amide; 6-Methyl-imidazo{2,1 -felthiazole-5-carboxylic acid-(1 S.2S,5R)-{3-[5-(4-chloro-phenyl)- 2-methyl-thiazole-4-carbonyl]-3-aza-bicyclo[3.3.0]oct72-ylmethyl}-amide; 6-Methyl-lmldazot2,1-dlthiazole-5-carboxylic acid-(1^,2S,5R)-{3-l2-methyl-5-(4- trifluoromethyl-phenyl)-thiazole-4-carbonyl]-3-aza-bicyclo[3.3.0]oct-2-ylmethyl}- amide; 1 i 6-Methyl-imidazo[2.1 -/)]thiazole-5-carboxylic acid-(1 S,2S,5R)-{3-l2-amino-S-(^-methyl-phenyl)-thiazole-4-carbonyl]-3-aza-bicyclo[3.3.0]oct-2-ylmethyl}-amlde; 6-Methyl-imidazo[2,1 -b]thiazole-5-carboxylic acid-{1 S,2S,5R)-{3-[2-amino-5-(3-fluoro-phenyl)-thiazole-4-carbonyl]-3-aza-bicyclo[3.3.0]oct-2-ylmethyl}-amide; 6-Methyl-imidazo[2,1-i»]thiazole-5-carboxylicacid-(1S,2S,5R)-[3-(2-amino-6-phenyl-thia2ole-4-carbonyl)-3-aza-bicyclo[3.3.0]oct-2-ylmethyl]-amide; 6-Methyl-imidazo[2,1-6]thiazole-5-carboxylic acid-(1S,2S,5R)-{7-methyl-3-[2-amlno-5-(3-methyl-phenyl)-thiazole-4-carbonyl]-3-aza-bicyclo[3.3.0Joct-2-ylmethyl}-amJde; 6-Methyl-imidazo[2,1-fc!]thiazole-5-carboxylic acid-(1 S,2S,5R)-{7-methyl-3-[2-amino-5-(4-fluoro-phenyl)-thiazole-4-carbonyl]-3-aza-blcyclo[3.3.0]Oct-2-ylmethyl>-amJde; 6-Methyl-imida2o[2,1-b]thiazole-5-carboxylic acid-(1 S,2S,5R)-{7-methyl-3-I2-amino-5-(3-fluoro-phenyl)-thidzole-4-carbonyl]-3-aza-bicyclo[3,3.0]oct-2-ylmethyl}-amide; lmidazo[2,1 -i)]thiazole-6-carboxylic acid-(1 S,2S,5R)-[3-(2-methyl-5-m-tolyl-thiazole-4-carbonyl)-3-aza-bkt:yclo[3.3.0]oct-2-ylmethyl]-amide; 2-Methyl-benzofuran-4-carboxylicacid-(1S,2S,5R)-[7v7-difluoro-3-(2-methyl-5-m-tolyl- thiazole-4-carbonyl)-3-aza-bicyclo[3.3.0]oct-3-ylmethyl]-amide; 3-Methyl-benzofuran-4-carboxyllcacid-(1S,2S,5R)-[7,7-difluoro-3-(2-methyl'5-m-tolyl- thiazole-4-carbonyl)-3-aza-bicyclo[3.3.0]oct-3-ylmethv|l]-amide; 2,3-Dihydro-benzofuran-4-carboxylic acid-(1S,2S,5R)-[7,7-difluoro-3'(2-methyl-5-m- tolyl-thiazole-4-carbonyl)"3-aza-bicyclo[3.3.0]oct-2-ylmethyQ-amide; 2,3-Dihydro-benzoI1,4]dloxine-5-carboxylic acid-(1 S,2S,5R)-[7,7-dlfluoro-3-(2-methyl- 5-m-tolyl-thlazole-4-carbonyl)-3-aza-bicyclo[3.3.0]oct-2-ylmethyl]-amlde; Benzothiazole-7-carboxylicacld-(1S,2S,5R)-[7,7-difluoro-3-(2-methyl-5-m-tolyl- thi3zole-4-carbonyl)-3-aza-bicyclo[3.3.0]oct-2-ylmethyl]-amlde; 6-Methyl-pyrrolo[2,1-b]thiazole-7-carboxylic ac}d-(1S,2S,5R)-I7.7-dlfluoro-3-(2- methyl-5-m-tolyl-thiazole-4-carbonyl)-3-aza-blcyclo[3.3.0]oct-2-ylmethyl]-afnide; lmidazol1,2-a]pyridine-3-carboxylic acid-(1S,2S,5R)-[7,7-difluoro-3-(2-methyl-5-m- tolyl-thiazole-4-carbonyl)-3-aza-bicyclo[3.3.0]oct-2-ylmethyO-amlde; 1-Methyl-indazole-3-carboxylic acid-(1 S,2S,5R)-[7,7-difluoro-3-(2-methyl-5-m-tolyl- thiazole-4-carbonyl)-3-aza-bicyclo[3.3.0]oct-2-ylmethyl]-amide; and 6-Methyl-imidazo[2,1-b]-thiazole-5-carboxylic acid-(1 S,2S,5R)-[7,7-difluoro-3-(2- methyl-5-m-tolyl-thiazole-4-carbonyl)-3-aza-bicyclo[3.3.0]oct-2-y«methyl]-amide; or a salt of such a compound 8. A pharmaceutical composition containing, as active principle, a compound of formula (I) according to claim 1, or a phamiaceuticalfy acceptable salt thereof, and at least one therapeutically inert excipient. 9. A compound of any one of claims 1 to 7, or a pharmaceutically acceptable salt thereof, for use as medicament. 10. A compound according to any of claims 1 to 7, or a pharmaceutically acceptable salt thereof, for the prevention or treatment of diseases selected from the group consisting of all types of sleep disorders, of stress-related syndromes, of psychoactive substance use, abuse, seeking and reinstatement, of cognitive dysfunctions In the healthy population and In psychiatric and neurologic disorders, of eating or drinking disorders. 11. Use of a compound according to any of claims 1 to 7, or a pharmaceutically acceptable salt thereof, for the preparation of a medicament for the preventton or treatment of diseases selected from the group consisting of all types of sleep disorders, of stress-related syndromes, of psychoactive substance use, abuse, seeking and reinstatement, of cognitive dysfunctions in the healthy population and in psychiatric and neurologic disorders, of eating or drinking disorders.