[0001] The invention relates to cyclic dithiocarbamates and more specifically a cyclic dithiocarbamates synthesis method, and more particularly to functionalized cyclic dithiocarbamates.
[0002] dithiocarbamates are organic compounds useful as precursors of radicals, intermediates of organic synthesis, vulcanizing agents, chelating agents or enzyme inhibitors. Their fields of application are diverse and they may for example in the composition of fungicides, herbicides, pesticides or insecticides in agriculture, be used in the rubber industry or in the pharmaceutical industry in the treatment of diseases such as cancer or HIV.

[0003] Due to the multitude of applications dithiocarbamates, there are various techniques of synthesis of these compounds.

[0004] Thus, the article Entesar A. Hassan, "Juventa dithiocarbamates as in organic chemistry, synthesis and uses", Phosphorus, Sulfur and Silicon, Vol. 189, (2014), pp. 300-323, describes various processes for the synthesis of dithiocarbamates. It is for example disclosed the synthesis of Ν, Ν-dialkyldithiocarbamate by reacting a dithiocarbamate salt with an alkyl halide or with a dialkyl phosphate, or by adding electron-deficient olefins. This article also describes obtaining dithiocarbamates by acylating amines of chlorodithioformate. There is also disclosed the preparation of cyclic dithiocarbamate disulfides by reaction with (i) 2-amino-ethanol sulfate, 2-aminoethyl and 2-aminoethyl halide, (ii) primary amines and 1, 2- dibromoethane in the presence of a base, (iii) aziridines and (iv) 2-iminothiazolidines. Cyclic dithiocarbamates also may be prepared by cyclisation of β-hydroxyalkyldithiocarbamates by treatment with mesyl chloride in pyridine, or by cyclization of 2-alkylaminoéthanethiol with thiophosgene in the presence of a base.

[0005] Furthermore, the CN 103 804 258 application describes the synthesis of dithiocarbamates from carbamide and carbon disulfide and the CN 103 804 257 application discloses the preparation diethyldithiocarbamates also from carbamide and carbon disulfide.

[0006] As for the application US 2,046,876, the latter describes the synthesis of N-diaryl-dithiocarbamates by adding carbon disulfide derivatives diarylamines.

[0007] It is easily understood that, because of the multitude of possible applications dithiocarbamates, there is an increasing need for new dithiocarbamates, especially new dithiocarbamates functionalized, especially for applications in polymerization (including a possible grafting an organic medium), for applications in devulcanization and others, but also, and more specifically, new optically active dithiocarbamates for many applications in medicine, biology, and others.

[0008] It is also understood by the description of methods of synthesis that there is also a need for dithiocarbamates synthesis with methods that can be called sustainable, that is to say achievable with soft conditions temperature and pressure in aqueous solution with pH close to neutral, and with raw materials of renewable origin, and generally more environmentally friendly.

[0009] It has now been discovered that it is possible to meet the objectives defined above, in whole or in part at least, by implementing the process according to the invention and as described below. Other objectives become apparent from the following description of the invention that follows.

[0010] Thus, according to a first aspect, the present invention relates to a method for synthesizing a cyclic dithiocarbamate functionalized of formula (I):

in which

- Ri is hydrogen or a branched hydrocarbon chain or unsubstituted, saturated or unsaturated, linear or cyclic, aromatic or not, having 1 to 20 carbon atoms, and may contain one or more heteroatoms selected from O, S, N, P and if ;

- X represents -C (= 0) - or -CH 2 -, or -CN;

- R.2 is (i) zero (when X is -CN), (ii) hydrogen, (iii) -OR3, wherein R3 is hydrogen or a branched hydrocarbon chain or unsubstituted, saturated or unsaturated, linear or cyclic, aromatic or not, having 1 to 20 carbon atoms, and may contain one heteroatom selected from O, S, N, P and Si, (iv) -NR4R5 with R 4 and R 5 , different or not, being hydrogen or a branched hydrocarbon chain or unsubstituted, saturated or unsaturated, linear or cyclic, aromatic

or not, having 1 to 20 carbon atoms, and may contain one or more heteroatoms selected from O, S, N, P and Si;

- n is 0, 1 or 2, preferably 1; and

- * represents an asymmetric carbon,

said method comprising the steps of:

a / providing at least one compound of formula (II):

G- (CH 2 ) n C * H (NHR) -X-R 2 (II) wherein

- n, Ri, R2, X and * are as defined above,

- G represents either (i) R 6 -C (= 0) -0-CH 2 -, or (ii) (R 7 0) (R 8 0) -P (= 0) -0-CH 2 -, or

- R6 is hydrogen or a branched hydrocarbon chain or unsubstituted, saturated or unsaturated, linear or cyclic, aromatic or not, having 1 to 20 carbon atoms, and may contain one or more heteroatoms selected from O, S, N, P and if ;

- R 7 and Rs, identical or different, are selected independently of one another from H proton, an alkali, alkaline earth or ammonium, preferably a proton H or an alkali, and more particularly to a proton H or Na,

b / providing at least one inorganic trithiocarbonate,

cl reaction between said at least one compound of formula (II) and said at least inorganic trithiocarbonate in the presence of at least one enzyme selected from sulfhydrylases, and preferably a sulfhydrylase associated with said compound of formula (II),

d / obtaining at least one cyclic dithiocarbamate functionalized of formula (I), e / separating and isolating said at least one cyclic dithiocarbamate functionalized of formula (I),

f / optionally, further functionalization of the cyclic dithiocarbamate functionalized of formula (I) obtained in step d / or e /,

steps a / and b / is or not performed simultaneously.

[0011] It was observed that the asymmetric carbon configuration is maintained throughout the reaction. As a further advantage, it should be noted that the cyclic dithiocarbamate functionalized of formula (I) obtained according to the method of the invention is an enantiomerically pure dithiocarbamate.

[0012] The term "cyclic dithiocarbamate functionalized" is meant any type of cyclic dithiocarbamate of formula (I) in which the nitrogen atom carries a functional group (except when R represents the hydrogen atom) and / or carbon atom alpha to the nitrogen atom carries a functional group (except when -X- is -CH2- and R2 the hydrogen atom).

[0013] The invention will be better understood in light of the description and the following examples but is in no way limited to the said examples.

[0014] According to one embodiment of the invention, Ri represents hydrogen.

[0015] According to another embodiment of the invention, -X- is -C (= 0) -.

[0016] According to yet another embodiment of the invention, R 2 is -OR 3 with R 3 being hydrogen.

[0017] According to another embodiment of the invention, n is 0.

[0018] According to yet another embodiment of the invention, n is 1.

[0019] According to a preferred embodiment of the invention, in formula (I), R represents hydrogen, -X- is -C (= 0) -, R 2 represents -OR 3 with R3 is hydrogen, n is 0, and the compound of formula (I) is L-raphanusamique.

[0020] According to another preferred embodiment of the invention, in formula (I), R represents hydrogen, -X- is -C (= 0) -, R 2 represents -OR3 with R3 being a hydrogen atom, n is equal to 1, and the compound of formula (I) is L-homoraphanusamique.

[0021] According to a preferred embodiment of the invention, in formula (II), R represents hydrogen, -X- is -C (= 0) -, R 2 represents -OR 3 with R3 is hydrogen, n is 0, and the compound of formula (II) is a derivative of L-serine.

[0022] The derivative of L-serine used in the process according to the invention may, for example and without limitation, be selected from O-phospho-L-serine, O-succinyl-L-serine , O-acetyl-L-serine, ΓΟ-acetoacetyl-L-serine, O-propio-L-serine, O-coumaroyl-L-serine, O-malonyl-L-serine, O- hydroxymethylglutaryl-L-serine, O-pimelyl-L-serine, and O-sulfato-L-serine.

[0023] Preferably, the derivative of L-serine is selected from O-phospho-L-serine, O-succinyl-L-serine, O-acetyl-L-serine, and O-sulfato L-serine.

[0024] Most preferably, the L-serine derivative is O-acetyl-L-serine.

[0025] According to another preferred embodiment of the invention, in formula (II), R represents hydrogen, X represents the function C = 0, R 2 represents -OR 3 with R 3 being hydrogen , n is 1, and the compound of formula (II) is a derivative of L-homoserine.

[0026] The derivative of L-homoserine used in the process according to the invention may, for example and without limitation, be selected from O-phospho-L-homoserine, O-succinyl-L-homoserine, O-acetyl-L-homoserine, O-acetoacetyl-L-homoserine,

UR-propio-L-homosérine, UR-coumaroyl-L-homosérine, UR-malonyl-L-homosérine, UR-hydroxyméthylglutaryl-L-homosérine, UR-pimélyl-L-homosérine et UR-sulfato-L-homosérine.

[0027] De manière music, drifts of L-east Homoserine Das Models O-phospho-L-Homoserine, ΓΟ-succinyl-L-Homoserine, ΓΟ-acetyl-L-Homoserine and the O-sulfate-L- Homoserine.

[0028] Most preferably, the derivative of L-homoserine is rO-acetyl-L-homoserine (OAHS).

[0029] The derivative of L-serine and the derivative of L-homoserine are either commercially available or obtained by any known to those skilled in the art.

[0030] They can for example be obtained by fermentation of a renewable raw material. The renewable raw material may be selected from glucose, sucrose, starch, molasses, glycerol, ethanol, preferably glucose.

[0031] The derivative of L-serine can also be produced from the acetylation of L-serine, L-serine, which can itself be obtained by fermentation of a renewable raw material. The renewable raw material can be selected from glucose, sucrose, starch, molasses, glycerol, ethanol, preferably glucose.

[0032] The derivative of L-homoserine can also be produced from the acetylation of L-homoserine, L-homoserine, which can itself be obtained by fermentation of a renewable raw material. The renewable raw material may be selected from glucose, sucrose, starch, molasses, glycerol, ethanol, preferably glucose.

[0033] The trithiocarbonate inorganique used in the invention procédé selon peut être Das Models of alkalisch a trithiocarbonate, a trithiocarbonate of alkaline terreux or a trithiocarbonate of ammonium.

[0034] Preferably, the inorganic trithiocarbonate is selected from sodium trithiocarbonate, potassium trithiocarbonate, calcium trithiocarbonate and ammonium trithiocarbonate.

[0035] Particularly preferably, the inorganic trithiocarbonate is sodium trithiocarbonate.

[0036] In the process according to the invention, the reaction between said at least one compound of formula (II) and said at least inorganic trithiocarbonate is carried out in the presence of at least one enzyme, said enzyme being preferably associated sulfhydrylase to said compound of formula (II).

[0037] Thus, when the compound of formula (II) is a derivative of L-serine, the enzyme used may be selected from sulfhydrylase ΓΟ-phospho-L-serine sulfhydrylase the O-succinyl-L-serine, sulfhydrylase ΓΟ-acetyl-L-serine sulfhydrylase ΓΟ-acetoacetyl-L-serine sulfhydrylase ΓΟ-propio-L-serine sulfhydrylase ΓΟ-coumaroyl-L-serine sulfhydrylase ΓΟ-malonyl-L-serine, ΓΟ-hydroxymethylglutaryl-L serine sulfhydrylase, O-pimelyl-L-serine sulfhydrylase and sulfhydrylase ΓΟ-sulfato-L-serine.

[0038] Preferably, the enzyme associated with the derivative of L-serine is selected from sulfhydrylase ΓΟ-phospho-L-serine sulfhydrylase ΓΟ-succinyl-L-serine sulfhydrylase and ΓΟ- ΓΟ-acetyl-L-serine sulfhydrylase sulfate-L-serine.

[0039] Most preferably, the enzyme associated with the derivative of L-serine sulfhydrylase is ΓΟ-acetyl-L-serine.

[0040] Furthermore, when the compound of formula (II) is a derivative of L-homoserine, the enzyme used may be selected from O-phospho-L-homoserine sulfhydrylase, O-succinyl-L -homosérine sulfhydrylase, ΓΟ-acetyl-L-homoserine sulfhydrylase, the O-aceto-acetyl-L-homoserine sulfhydrylase, the O-propio-L-homoserine sulfhydrylase, the O-coumaroyl-L-homoserine sulfhydrylase, ΓΟ- malonyl-L-homoserine sulfhydrylase, the O-hydroxymethyl-glutaryl-L-homoserine sulfhydrylase, the O-pimelyl L-homoserine sulfhydrylase and O-sulfato-L-homoserine sulfhydrylase.

[0041] Preferably, the enzyme associated with the derivative of L-homoserine is selected from O-phospho-L-homoserine sulfhydrylase, O-succinyl-L-homoserine sulfhydrylase, the O-acetyl-L -homosérine sulfhydrylase and ΓΟ-sulfate-L-homoserine sulfhydrylase.

[0042] Most preferably, the enzyme associated with the derivative of L-homoserine is O-acetyl-L-homoserine sulfhydrylase.

[0043] These enzymes have called optimal operation, as is well known in the art, when used in the presence of a cofactor, such as for example pyridoxal-5'-phosphate (PLP).

[0044] The enzyme and its cofactor associated are generally dissolved in water before being added to the reaction medium. The proportion of enzyme in relation to the weight of the compound of formula (II) will be between 0.1% and 10% by weight, preferably between 1% and 5% by weight, and the amount of co-factor with respect to compound of formula (II) will be between 0.1% and 10% by weight, preferably between 0.5% and 5% by weight.

[0045] Regarding the pH conditions, temperatures, synthetic medium, one can refer to those described in WO2008013432 and WO2013029690 applications.

[0046] Thus, the reaction pH is preferably between 5 and 8, preferably between 6 and 7.5, more particularly between 6.2 and 7.2. Said pH is a function of the operating domain of the enzyme and can be regulated according to the optimum of the enzyme, by addition of basic trithiocarbonate or by adding dilute sulfuric or ammonia diluted acid. Preferably, the pH is adjusted by regulation of the addition of basic trithiocarbonate.

[0047] Thus, the temperature during the reaction is between 10 ° C and 45 ° C, preferably between 20 ° C and 40 ° C, more particularly between 25 ° C and 35 ° C. Said temperature is selected according to the operating range of the enzyme.

[0048] The reaction proceeds in aqueous medium or in the presence of organic solvents if they are compatible with the enzymes used. Preferably, the reaction takes place in aqueous medium.

[0049] The reaction may be conducted in batch, semi-continuously or continuously. Any type of reactor known to the skilled person, may be suitable for such reactions.

[0050] According to one embodiment of the invention, the separation and isolation of the obtained dithiocarbamate can be carried out according to any technique known to those skilled in the art, in particular by precipitation and filtration.

[0051] Step f / optional process according to the invention allows to obtain additional and different functions from those obtained after step d / or e / step.

[0052] Indeed, the cyclic dithiocarbamate functionalized of formula (I) obtained at the end of step d / or after step e / may again be functionalized at this stage f /. For example, if X-R2 represents a carboxylic function, it can be esterified, reduced aldehyde, reduced to the alcohol and then etherified, amidated, or other nitrilée. All functions can be obtained by techniques well known to the skilled man, depending on the final use which is intended dithiocarbamate.

[0053] Thus, the cyclic dithiocarbamate functionalized of formula (I) obtained at the end of step d / or e / may be subjected to one or more additional chemical reactions to obtain one or more dithiocarbamate with different functions, said chemical reactions are all reactions known to those skilled in the art.

[0054] According to one embodiment of the invention, are brought into a derivative of L-serine as ΓΟ-acetyl-L-serine, an enzyme such as ΓΟ-acetyl-L-serine sulfhydrylase, cofactor, such the pyridoxal-5'-phosphate (PLP), and the basic trithiocarbonate, such as sodium trithiocarbonate, it is found surprisingly that a major product obtained is a cyclic dithiocarbamate responsive to the acid name L- raphanusamique the raphanusamique acid being represented by the formula:

[0055] According to another embodiment of the invention, are brought into a derivative of L-homoserine as ΓΟ-acetyl-L-homoserine, an enzyme such as O-acetyl-L-homoserine sulfhydrylase, a cofactor, such as pyridoxal-5'-phosphate (PLP), and the basic trithiocarbonate, such as sodium trithiocarbonate. It turns out, surprisingly, that one of the main products obtained is a cyclic dithiocarbamate by the name of L-homoraphanusamique acid (cyclic higher homologue of L-raphanusamique), the ho ic acid being represented by the formula :

[0056] It has been observed that the synthesis of the dithiocarbamate can be accompanied by the production of a mercaptan of formula (III): HS-CH2 (CH2) n * H (NHR) -X-R2 wherein n, R , R2, X and * are as defined above. This mercaptan can advantageously be used as raw material for the synthesis of the dithiocarbamate by reaction with basic medium carbon disulfide.

[0057] For example, in the case of the synthesis of homoraphanusamique acid, mercaptan produced is homocysteine ​​reacts with carbon disulfide according to the following scheme:

[0058] The compound in square brackets is an intermediate compound that appears during the process. This compound, as well as other alkali salts, alkaline earth metal or ammonium, are novel and as such form part of the present invention. These compounds are named in the following "trithiocabonates" ( "sodium trithiocarbonate" in the case where the against-ion is sodium ion) of homocysteine.

[0059] More generally, the intermediate compound may be a compound of formula (IV):

X2 + O - C = (S) -S-CH2- (CH 2 ) n H (NHR) -X-R 2 (IV) wherein Ri, R2, X, n and * are as hereinbefore defined and X2 represents an alkali, alkaline earth, or an ammonium group, preferably Na, K, NH4 or Ca, preferably Na yet.

[0060] According to another preferred embodiment of the invention, carbon disulfide may be added continuously or batchwise during the reaction.

[0061] The addition of carbon disulfide notably allows to increase the yield of synthesis dithiocarbamate.

[0062] According to a preferred embodiment of the invention, the derivative of L-serine is O-acetyl-L-serine, trithiocarbonate is sodium trithiocarbonate and the enzyme used is O-acetyl -L-serine sulfhydrylase.

[0063] According to a preferred embodiment of the invention, the cyclic dithiocarbamate functionalized of formula (I) obtained according to the process is L-raphanusamique.

[0064] According to another preferred embodiment of the invention, the derivative of L-homoserine is ΓΟ-acetyl-L-homoserine, trithiocarbonate is sodium trithiocarbonate and the enzyme used is the O-acetyl-L -homosérine sulfhydrylase.

[0065] According to a preferred embodiment of the invention, the cyclic dithiocarbamate functionalized of formula (I) obtained according to the process is L-homoraphanusamique.

[0066] As indicated above, the asymmetric carbon configuration is maintained throughout the reaction. This provides a particular enantiomer which can be an advantage for some applications, particularly in the medical or pharmaceutical field.

[0067] In addition, the carboxylic acid present on the functionalized dithiocarbamate of formula (I) may allow to "hook" a wide variety of compounds or molecules enabling grafting on organic or inorganic support.

[0068] The cyclic dithiocarbamate functionalized of formula (I) prepared by the process according to the invention can be used as precursors of radicals, intermediates of organic synthesis, vulcanizing agents, chelating agents or enzyme inhibitors. Their fields of application are diverse and they may for example in the composition of fungicides, herbicides, pesticides or insecticides in agriculture, be used in the rubber industry or in the pharmaceutical industry in the treatment of diseases such as cancer or HIV.

EXAMPLES

EXAMPLE 1 Enzymatic synthesis of L-homoraphanusamique

Step 1 :

[0069] The O-acetyl-L-homoserine (OAHS) was synthesized from L-homoserine and acetic anhydride according Sadamu Nagai, "Synthesis of O-acetyl-L-homoserine," Academic Press, (1971 ), vol.17, pp. 423-424.

2nd step :

[0070] In a thermostated glass reactor of 250 ml, are introduced 10 g (62 mmol) of OAHS previously synthesized, in 140 mL of distilled water. The solution was heated at 35 ° C with mechanical stirring. The pH of the reaction medium is 4.8. Before adding the enzyme, the pH is set at 6.5 with a few drops of sodium trithiocarbonate solution (4.78 g; 31 mmol, dissolved in 20 mL of distilled water). a sampling is carried out (at t = 0) 1 mL of the reaction medium. A solution of pyridoxal-5'-phosphate (10 mmol, 0.4 g) and the enzyme, the O-acetyl-L-homoserine sulfhydrylase, (0.6 g) are dissolved in 10 mL of water and then added in the reactor.

[0071] The reaction begins, which causes a decrease in pH. The reaction medium is maintained at a pH of 6.5 by sodium trithiocarbonate added slowly via the dropping funnel. Samples (1 ml) are carried out during the reaction. Analyzes by potentiometry, TLC, HPLC and UPLC / UV-mass show a gradual disappearance of the reagents (OAHS and Na2CS3) and the gradual appearance in amounts more and more important, the co

[0072] This intermediate disappears in turn gradually to give equimolar amount:

L-homoraphanusamique (cyclic dithiocarbamate functionalized)

and L-homocysteine

[0073] The only other product observed after the total disappearance of the OAHS are traces of homoserine (hydrolysis OAHS).

Step 3: Separation and isolation of dithiocarbamate:

[0074] The reaction medium is concentrated by partial evaporation of the water (so as to avoid precipitation of sodium acetate present in the reaction medium) under reduced pressure at 30 ° C. A precipitate formed as the dithiocarbamate proves to be the less soluble compounds present in the reaction medium. After filtration and drying, 4.9 g of dithiocarbamate. The overall isolated yield of dithiocarbamate is 45% (4.9 g obtained 1 g of 1 theoretically expected). Further analysis of this dry product showed that this solid contains only traces of homocysteine.

Example 2: Synthesis of dithiocarbamate (without enzyme or coenzyme)

[0075] Example 1 was repeated with the only difference that the pyridoxal-5'-phosphate solution (10 mmol; 0.4 g) and the enzyme, ΓΟ-acetyl-L-homoserine sulfhydrylase (0.6 g) dissolved in 10 ml of water were not added into the reactor. It turns out that the reaction does not start and it is not possible to continually add the trithiocarbonate solution seeking to maintain a pH of 6.5. By increasing pH 8, then at pH 12 by adding sodium trithiocarbonate solution, the only reaction observed is a hydrolysis early in OAHS homoserine. This example shows that the synthesis of dithiocarbamate to be catalyzed by an enzyme to perform.

Example 3: Enzymatic Synthesis of dithiocarbamate (with addition of CS2 end of the reaction)

Step 1 :

[0076] The synthesis of ΓΟ-acetyl-L-homoserine (OAHS) from L-homoserine was carried out according to a protocol derived from the literature (Sadamu Nagai, "Synthesis of O-acetyl-homoserine", Academic Press, ( 1971), vol.17, pp. 423-424).

2nd step :

[0077] In a thermostated glass reactor of 250 ml, are introduced 10 g (62 mmol) in 140 mL OAHS of distilled water. The solution was heated at 35 ° C with mechanical stirring. The pH of the reaction medium is 4.8. Before adding the enzyme, the pH is set to 6.5 by adding a few drops of sodium trithiocarbonate solution (the total amount added throughout the reaction is equal to 4.78 g, 31 mmol , dissolved in 20 mL of distilled water). a sampling is carried out (at t = 0) 1 mL of the reaction medium.

[0078] Prepare a 10 ml distilled water solution containing 400 μί a pyridoxal-5'-phosphate solution (10 mmol / L) and 0.6 g of enzyme (O-acetyl-L- homoserine sulfhydrylase). A decrease in pH indicate the formation of acetic acid makes it possible to say that the reaction begins. It is necessary to maintain the reaction medium at a pH equal to 6.5. For this, the sodium trithiocarbonate solution is slowly added via the dropping funnel. Samples (1 ml) are carried out during the reaction.

[0079] When the analyzes by potentiometry indicate a 50% conversion of homocysteine ​​OAHS, 1, 87 mL carbon disulfide (31 mmol) were added to the reaction medium. The pH of the reaction medium is adjusted to 10 with a sodium hydroxide solution 1 M. The reaction medium is then brought to 50 ° C. A disappearance of cysteine ​​by potentiometric analysis is observed. Hydrochloric acid solution (2N) was then used to lower the pH to 5 of the reaction medium.

[0080] Further analysis by TLC, HPLC and UPLC / UV-mass showed the formation of a major product of L-homoraphanusamique acid.

[0081] The only other product observed after the total disappearance of the OAHS are traces of homoserine (hydrolysis OAHS) and trace amounts of homocysteine.

Step 3: Separation and isolation of the dithiocarbamate

[0082] The reaction medium is concentrated by partial evaporation of the water (so as to avoid precipitation of sodium acetate and other salts present in the reaction medium) under reduced pressure at 30 ° C. Thus a precipitate forms because dithiocarbamate proves to be the case the less soluble in water. After filtration and drying, 9.2 g of dithiocarbamate. The overall isolated yield of dithiocarbamate is from 9.2 g of 1 1 g or 84% theoretical.

Example 4: Enzymatic Synthesis of dithiocarbamate (with addition of CS2 during the reaction)

Step 1 :

The synthesis of ΓΟ-acetyl-L-homoserine (OAHS) from L-homoserine was carried out according to a protocol derived from the literature (source: "Sadamu Nagai Synthesis of O-acetyl-homoserine," Academic Press, (1971 ), vol.17, pp. 423-424).

2nd step :

In a thermostatically controlled glass reactor of 250 ml, are introduced 10 g (61 mmol) of OAHS previously synthesized in 140 mL of distilled water. The solution was heated at 35 ° C with mechanical stirring. The pH of the reaction medium is 4.8. Before placing the enzyme, the pH is set to 7.2 by adding few drops of the trithiocarbonate solution and carbon disulfide (4.78 g trithiocarbonate, 31 mmol, 1 87 ml of carbon disulfide, 31 mmol dissolved in 20 mL of distilled water).

[0083] a sample is taken (t = 0) 1 mL of the reaction medium. Preparing a distilled 10 ml of water solution containing 400 μί a pyridoxal-5'-phosphate solution (10 mmol / L) and 0.6 g of enzyme (O-acetyl-L-homoserine sulfhydrylase). A decrease in pH indicate the formation of acetic acid makes it possible to say that the reaction begins. It is necessary to maintain the reaction medium at a pH equal to 7.2. For that sodium trithiocarbonate solution is added slowly via the dropping funnel. of the

samples (1 mL) were made during the reaction. Analyzes by potentiometry, TLC, HPLC and UPLC / UV-mass (after derivatisation) show a gradual disappearance of the reagents (OAHS and Na2CS3) and the gradual appearance in an amount of more and more of the L-homoraphanusamique. When all of the OAHS reacted, the medium pH is lowered to 5 with a 2M hydrochloric acid solution.

[0084] is obtained L-homoraphanusamique acid (dithiocarbamate).

[0085] The derivatization method for UPLC / UV-mass was made by the same method described in Example 1.

[0086] The only other product observed after the total disappearance of the OAHS are traces of homoserine (hydrolysis OAHS) and trace amounts of homocysteine.

Step 3: Separation and isolation of the dithiocarbamate

[0087] The reaction medium is concentrated by partial evaporation of the water (so as to avoid precipitation of sodium acetate and other salts present in the reaction medium) under reduced pressure at 30 ° C. Thus a precipitate forms because dithiocarbamate proves to be the case the less soluble in water. After filtration and drying, 8.3 g of dithiocarbamate. The total isolated yield is 8.3 g of dithiocarbamate of 1 1 g theoretical or 75.4%.

CLAIMS
1. A method of synthesizing a cyclic dithiocarbamate functionalized of formula (I):

in which

- Ri is hydrogen or a branched hydrocarbon chain or unsubstituted, saturated or unsaturated, linear or cyclic, aromatic or not, having 1 to 20 carbon atoms, and may contain one or more heteroatoms selected from O, S, N, P and if ;

- X represents -C (= 0) - or -CH 2 -, or -CN;

- R2 is (i) zero (when X is -CN), (ii) hydrogen, (iii) -OR3, wherein R3 is hydrogen or a branched hydrocarbon chain or unsubstituted, saturated or unsaturated, linear or cyclic, aromatic or not, having 1 to 20 carbon atoms, and may contain one heteroatom selected from O, S, N, P and Si, (iv) -NR4R5 with R 4 and R 5 , different or not, being a hydrogen or a branched hydrocarbon chain or unsubstituted, saturated or unsaturated, linear or cyclic, aromatic or not, having 1 to 20 carbon atoms, and may contain one or more heteroatoms selected from O, S, N, P and Si;

- n is 0, 1 or 2, preferably 1; and

- * represents an asymmetric carbon,

said method comprising the steps of:

a / providing at least one compound of formula (II):

G- (CH 2 ) n C * H (NHR) -X-R 2 (II) wherein

- n, Ri, R2, X and * are as defined above,

- G represents either (i) R 6 -C (= 0) -0-CH 2 -, or (ii) (R 7 0) (R 8 0) -P (= 0) -0-CH 2 -, or

- R6 is hydrogen or a branched hydrocarbon chain or unsubstituted, saturated or unsaturated, linear or cyclic, aromatic or not, having 1 to 20 carbon

atoms, and may contain one or more heteroatoms selected from O, S, N, P and Si;

- R 7 and Rs, identical or different, are selected independently of one another from H proton, an alkali, alkaline earth or ammonium, preferably a proton H or an alkali, and more particularly to a proton H or Na,

b / providing at least one inorganic trithiocarbonate,

cl reaction between said at least one compound of formula (II) and said at least inorganic trithiocarbonate in the presence of at least one enzyme selected from sulfhydrylases, and preferably a sulfhydrylase associated with said compound of formula (II),

61 obtaining at least one cyclic dithiocarbamate functionalized of formula (I), e / separating and isolating said at least one cyclic dithiocarbamate functionalized of formula (I),

f / optionally, further functionalization of the cyclic dithiocarbamate functionalized of formula (I) obtained in step d / or e /,

al steps and b / is or not performed simultaneously.

2. The method of claim 1 wherein the cyclic dithiocarbamate functionalized of formula (I) is enantiomerically pure.

3. Method according to one of the preceding claims wherein the cyclic dithiocarbamate functionalized of formula (I) is L-or L-raphanusamique homoraphanusamique acid.

4. Method according to one of the preceding claims wherein the compound of formula (II) is selected from the derivatives of L-serine and the derivatives of L-homoserine.

5. The method of claim 4 wherein the derivative of L-serine is selected from ΓΟ-phospho-L-serine, ΓΟ-succinyl-L-serine, ΓΟ-acetyl-L-serine, O-acetoacetyl-L serine, O-propio-L-serine, O-coumaroyl-L-serine, O-malonyl-L-serine, O-hydroxymethylglutaryl-L-serine, O-pimelyl-L-serine and O-sulfato-L-serine, preferably ΓΟ-phospho-L-serine, ΓΟ-succinyl-L-serine, ΓΟ-acetyl-L-serine, and O-sulfato-L-serine, and more particularly O- acetyl-L-serine.

6. The method of claim 4 wherein the derivative of L-homoserine is selected from ΓΟ-succinyl-L-homoserine, O-acetyl-L-homoserine, O-acetoacetyl-L-homoserine, O -propio-L-homoserine, ΓΟ-coumaroyl-L-homoserine, O-malonyl

L-Homoserine, ΓΟ-hydroxyméthylglutaryl-L-Homoserine, ΓΟ-pimélyl-L-Homoserine, ΓΟ-phospho-L-Homoserine and ΓΟ-sulfato-L-Homoserine, de préférence O-succinyl-L-Homoserine, the ' O-acetyl-L-Homoserine, ΓΟ-phospho-L-Homoserine and the O-sulfate-L-Homoserine, et plus particulièrement ΓΟ-acetyl-L-Homoserine.

7. Method according to one of the preceding claims wherein the sulfhydrylase is selected from sulfhydrylases associated with derivatives of L-serine and sulfhydrylases associated with derivatives of L-homoserine.

8. The method of claim 7 wherein the sulfhydrylase associated with the derivative of L-serine is selected from sulfhydrylase ΓΟ-phospho-L-serine, ΓΟ-succinyl-L-serine sulfhydrylase, sulfhydrylase ΓΟ-acetyl-L-serine, ΓΟ sulfhydrylase -acétoacétyl-L-serine sulfhydrylase ΓΟ-propio-L-serine sulfhydrylase ΓΟ-coumaroyl-L-serine sulfhydrylase ΓΟ-malonyl-L-serine sulfhydrylase ΓΟ-hydroxymethylglutaryl-L-serine, L- ΓΟ-pimelyl sulfhydrylase serine and ΓΟ-sulfato-L-serine sulfhydrylase, preferably sulfhydrylase ΓΟ-phospho-L-serine sulfhydrylase ΓΟ-succinyl-L-serine sulfhydrylase ΓΟ-acetyl-L-serine and sulfhydrylase ΓΟ-sulfato-L-serine, especially sulfhydrylase ΓΟ-acetyl-L-serine.

9. The method of claim 7 wherein the sulfhydrylase associated with the derivative of L-homoserine is selected from ΓΟ-phospho-L-homoserine sulfhydrylase, O-succinyl-L-homoserine sulfhydrylase, ΓΟ-acetyl-L-homoserine sulfhydrylase , O-acetoacetyl-L-homoserine sulfhydrylase, ΓΟ-propio-L-homoserine sulfhydrylase, the O-coumaroyl-L-homoserine sulfhydrylase, ΓΟ-malonyl-L-homoserine sulfhydrylase, the O-hydroxymethyl-glutaryl-L -homosérine sulfhydrylase, ΓΟ pimelyl-L-homoserine sulfhydrylase and O-sulfato-L-homoserine sulfhydrylase, preferably ΓΟ-phospho-homoserine sulfhydrylase, rO-succinyl-L-homoserine sulfhydrylase, ΓΟ-acetyl-L-homoserine sulfhydrylase and rO-sulfate-L-homoserine sulfhydrylase, especially ΓΟ-acetyl-L-homoserine sulfhydrylase.

10. Procédé selon l'une des quelconque revendications précédentes est le trithiocarbonate inorganique east Das Models of alkalisch a trithiocarbonate, a trithiocarbonate of alkaline terreux or a trithiocarbonate of ammonium, de préférence the trithiocarbonate of sodium, the potassium trithiocarbonate , the trithiocarbonate of calcium and phosphate of the trithiocarbonate, et plus particulièrement the trithiocarbonate of sodium.

11. A method according to any preceding claim having an f / optional step of further functionalization of the cyclic dithiocarbamate functionalized of formula (I) obtained in step d / or e / step.

12. Dithiocarbamate cyclic functionalized of formula (I) prepared according to the method described in claims 1 to 1 of 1.

13. Acid L-raphanusamique or L-homoraphanusamique prepared according to the method described in claims 1 to 12.

14. Sodium trithiocarbonate of homocysteine ​​of formula (IV):

X2 + O - C = (S) -S-CH2- (CH 2 ) n C * H (NHR) -X-R 2 (IV) wherein Ri, R2, X, n and * are as defined in claim 1 and X2 represents an alkali, alkaline earth, or an ammonium group, preferably Na, K, NH4 or Ca, preferably Na yet.