1. Compound of formula (la) wherein: - R1 represents a chlorine atom, a methyl radical or a trifluoromethoxy radical; - R2 represents a hydrogen atom or is in position -6- of the indol-2-one and represents a chlorine atom, a methyl radical, a methoxy radical or a trifluoromethyl radical; - R3 represents a chlorine atom, a fluorine atom, a methoxy radical or an ethoxy radical; - R4 represents a hydrogen atom or is in position -3-or -4- of the phenyl and represents a fluorine atom or a methoxy radical; - or R4 is in position -3- of the phenyl and, together with R3, represent a methylenedioxy radical; - R5 represents a dimethylamino radical or a methoxy radical - R6 represents a hydrogen atom; a methyl radical; an ethyl radical; a tert-butyloxycarbonylmethyl radical; a carboxymethyl radical; a [[2-hydroxy -1- (hydroxymethyl) -1-methylethyl] amino] carbonylmethyl 1- (hydroxymethyl) -1-methylethyl] amino] carbonylmethyl radical; a (l-piperazinyl)carbonylmethyl radical; a (4-morpholinyl) carbonylmethyl radical; a 3- (4-morpholinyl)propanoyl radical; R7 is in position -2- of the phenyl and represents a methoxy radical; R8 represents a methoxy radical; and the salts thereof with mineral or organic acids, and the solvates and/or hydrates thereof.

2. Compound as claimed in claim 1, chosen from: (2S, 4R)-l-[5-Chloro-l-[ (2,4-dimethoxyphenyl)-sulphonyl] -3- (2- methoxy-phenyl) -2-oxo-2, 3-dihydro- lH-indol-3-yl] -4-hydroxy-N, N- dimethyl2-pyrrolidinecarboxamide, laevorotatory isomer; (2S, 4R)-l-[5-Chloro-l-[ (2,4-dimethoxyphenyl)- sulphonyl ]-3- (2- methoxyphenyl) -2-oxo-2, 3-dihydro- lH-indol-3-yl] -4-methoxy-N,N- dimethyl- 2 -pyrrolidinecarboxamide, laevorotatory isomer; (2S, 4R)-l-[5-Chloro-3-(2-chlorophenyl)-l- [(2, 4- dimethoxyphenyl) sulphonyl] -2-oxo- 2,3-dihydro-lH-indol-3-yl]-4-hydroxy- N,N-dimethyl- 2- pyrrolidinecarboxamide, laevorotatory isomer; (2S, 4R)-l-[5-Chloro-3~(2-chlorophenyl)- 1- [(2, 4-dimethoxyphenyl) sulphonyl]-6-methoxy-2-oxo- 2,3—dihydro-1H-indol-3-yl] -4-methoxy- N,N-dimethyl- 2-pyrrolidinecarboxamide, laevorotatory isomer; (2S, 4R)-l-[5-Methyl-l-[(2,4-dimethoxyphenyl)- sulphonyl] -3- (2 methoxyphenyl) -2-oxo-2, 3-dihydro- lH-indol-3-yl] -4-hydroxy-N,N dimethyl- 2 -pyrrolidinecarboxamide, laevorotatory isomer; (2S, 4R)-l-[5-Trifluoromethoxy-l-[(2, 4-dimethoxy- phenyl) sulphonyl] - 3- (2-methoxyphenyl) -2-oxo- 2,3-dihydro-lH-indol-3-yl] -4-hydroxy- N,N-dimethyl- 2- pyrrolidinecarboxamide, laevorotatory isomer; (2S, 4R)-l-[5-Chloro-l-[(2,4-dimethoxyphenyl)- sulphonyl]-3- (2- methoxyphenyl) -6—methyl-2-oxo- 2,3-dihydro-lH-indol-3-yl]-4- hydroxy-N,N-dimethyl- 2-pyrrolidinecarboxamide, laevorotatory isomer; (2S, 4R)-l-[3-(2-Chlorophenyl)-l-[(2,4-dimethoxy-phenyl) sulphonyl] -5, 6-dimethyl-2-oxo-2, 3-dihydro-lH-indol-3-yl] -4-hydroxy-N,N-dimethyl- 2-pyrrolidinecarboxamide, laevorotatory isomer; (2S, 4R)-l-[5-Chloro-l-[(2,4-dimethoxyphenyl)-sulphonyl] -3- (2, 3- dimethoxyphenyl) -2-oxo-2, 3-dihydro-lH-indol-3-yl] -4-methoxy-N,N- dimethyl- 2-pyrrolidinecarboxamide, laevorotatory isomer; (2S, 4 R) -1- [5 Chloro -l-[2,4 -dimenthoxyphenyl)- sulphonyl] -3- (2- methoxyphenyl)-6-trifluoromethyl-2- oxo-2, 3-dihydro-lH-indol-3- yl] - 4- methoxy-N, N-dimethyl-2-pyrrolidinecarboxamide, laevorotatory isomer; (2S, 4R)-l-[6-Chloro-l-[(2,4-dimethoxyphenyl)-sulphonyl] -3- (2-methoxyphenyl) -5-methyl-2-oxo-2, 3-dihydro-lH-indol-3-yl] -4-metboxy- N.N-dimethyl- 2-pyrrolidinecarboxamide, laevorotatory isomer; (2S, 4R)-l-[5-Chloro-l-[(2,4-dimethoxyphenyl)-sulphonyl] -3- (2- methoxyphenyl) -2-oxo-2, 3-dihydro-lH-indol-3-yl]-4-ethoxy-N,N- dimethyl-2-pyrrolidine-carboxamide, laevorotatory isomer; (2S, 4R)-l-[5-Chloro-l-[ (2,4-dimethoxyphenyl)-sulphonyl] -3- (2, 3- dimethoxyphenyl) -2-oxo-2, 3-dihydro-lH-indol-3-yl] -4-hydroxy-N,N- dimethyl- 2-pyrrolidinecarboxamide, laevorotatory isomer; (2S, 4R)-l-[5,6-Dichloro-3-(2-chlorophenyl)-l- [ (2,4-dimethoxyphenyl) sulphonyl]-2-oxo- 2, 3-dihydro-lH-indol-3-yl] -4-hydroxy-N,N- dimethyl- 2-pyrrolidinecarboxamide, laevorotatory isomer; Methyl (2S, 4R)-l-[5-chloro-l-[ (2,4-dimethoxyphenyl) sulphonyl]-3- (2-methoxyphenyl) -2-oxo-2, 3-dihydro-lH-indol-3-yl]-4-methoxy-2-pyrrolidinecarboxylate, laevorotatory isomer; Methyl (2S, 4R)-l-[5-chloro- 1- [(2, 4-dimethoxyphenyl)sulphonyl] -3-(2-methoxyphenyl) -6-methyl-2-oxo-2, 3-dihydro-lH-indol-3-yl] -4-methoxy-2-pyrrolidinecarboxylate, laevorotatory isomer; 2S, 4R)-l-[5-Chloro-l-[ (2,4-dimethoxyphenyl)-sulphonyl] -3- (2-ethoxyphenyl) -2-oxo-2, 3-dihydro-lH-indol-3-yl] -4-hydroxy-N,N-dimethyl-2-pyrrolidinecarboxamicide, laevorotatory isomer; 2S, 4R)-l-[5-Chloro-l-[(2,4-dimethoxyphenyl)-sulphonyl]-3- (2, 3-difluorophenyl) -2-oxo- 2,3-dihydro-lH-indol-3-yl]-4-hydroxy-N,N-dimethyl- 2-pyrrolidinecarboxamide, laevorotatory isomer; (2S, 4R)-l-[5-Chloro-l-[(2,4-dimethoxyphenyl-sulphonyl] -3- (2,4-dimethoxyphenyl) -2-oxo-2, 3-dihydro-lH-indol-3-yl]-4-hydroxy-N,N-dimethyl- 2-pyrrolidinecarboxamide, laevorotatory isomer; (2S, 4R)-l-[5-Chloro-l-[(2,4-dimethoxyphenyl)-sulphonyl] -3- (1, 3-benzodioxol-4-yl) -2-oxo-2,3-dihydro-lH-indol-3-yl] -4-hydroxy-N,N-dimethyl- 2-pyrrolidinecarboxamide, laevorotatory isomer; (2S, 4R)-1—[5,6-Dichloro-l-[(2,4-dimethoxyphenyl)sulphonyl]-3-(2-methoxyphenyl) -2-oxo-2,3-dihydro-lH-indol-3-yl]-4-hydroxy-N, N- dimethyl-2-pyrrohidinecarboxamide, laevorotatory isomer; tert-Butyl 2-[[(3R, 5S)-l-[5-chloro-l-[(2,4—dimethoxyphenyl) sulphonyl] -3- (2-methoxyphenyl) -2-oxo-2, 3-dihydro-1H-indol-3-yl] -5- [ (dime thy lamino)carbonyl 1 -3-pyrrolidinyl]oxylacetate, laevorotatory isomer; 2-[[(3R, 5S)-1—[5-Chloro-l-(2,4— dimethoxyphenyl) sulphonyl] -3- (2- methoxyphenyl) -2-oxo-2, 3-dihydro-lH-indol-3-yl] -5- [(dimethylamino)carbonyl -3-pyrrolidinyl]oxy] acetic acid, laevorotatory isomer; (2S, 4R)-l-[5-Chloro-l-[(2,4-dimethoxyphenyl)-sulphonyl]-3- (2- methoxyphenyl) -2-oxo-2,3-dihydro-lH-indol-3-yl] -4- [2-[ [2-hydroxy-l- (hydroxymethyl) -1-methylethyl] amino] -2-oxoethoxy] -N,N-dlmethyl- 2-pyrrolidinecarboxamide, laevorotatory isomer; (2S, 4R)-l-[5-Chloro-l-[ (2,4-dimethoxyphenyl)-sulphonyl] -3- (2- methoxyphenyl) -2-oxo-2, 3-dihydro- lH-indol-3-yl] -N,N-dimethyl -4- [2-oxo- 2- (1-piperazinyl) ethoxy] -2-pyrrolidinecarboxamide, laevorotatory isomer; (2S, 4R)-1- [ [ (2,4-Dimethoxyphenyl)sulphonyl]- 3- (2- methoxyphenyl)-2-oxo-2,3-dihydro-lH-indol-3-yl] -N,N-dimethyl-4- [2- oxo-2- (4-morpholinyl) ethoxy] -2-pyrrolidinecarboxamide, laevorotatory isomer; (3R, 5S)-l-[5-Chloro-l-[(2,4-dimethoxyphenyl)- sulphonyl] -3- (2- methoxy-phenyl) -2-oxo-2, 3-dihydro-lH-indol-3-yl] -5-[ (dimethylamino) carbonyl] - 3-pyrrolidinyl 3- (4-morphcolinyl) propanoate, laevorotatory isomer; as well as the possible salts thereof with mineral or organic acids, and the solvates and/or hydrates thereof.

3. Compound as claimed in claim 2 which is : -(2S, 4R)-l-[5-Chloro-l-[(2,4-dimethoxyphenyl) -sulphonyl] -3- (2-methoxyphenyl) -2-oxo-2, 3-dihydro-lH-indol-3-yl] -4-hydroxy-N,N-dimethyl-2- pyrrolidinecarboxamide, laevorotatory isomer.

4. Process for preparing compounds of formula (la) laevorotatory isomer as claimed in claim 1, possible salts thereof with mineral or organic acids and solvates and/or hydrates thereof, characterized in that: wherein the carbon atom bearing substituent OR6 has the (R) configuration, Ri, R2, R3, R4, R5 and R are as defined for a compound of formula (la) laevorotatory isomer in Claim 1, is reacted, in the presence of a base, with a halide of formula: (III) in which R7 and R8 are as defined for a compound of formula (la) laevorotatory isomer in Claim 1 and Hal represents a halogen atom. Dated this

2002. 2nd day of July, (RANJNAJWEHTA-DUTT) OF REMFRY 8B SAGAR ATTORNEY FOR THE APPLICANTS

FORM 2 THE PATENTS ACT 1970 [39 OF 1970] & THE PATENTS RULES, 2003 COMPLETE SPECIFICATION [See Section 10; rule 13] "NOVEL l,3-DIHYDRO-2H-INDOL-2-ONE COMPOUNDS" SANOFI-SYNTHELABO, of 174, Avenue de France, F-75013, Paris, France, The following specification particularly describes the invention and the manner in which it is to be performed: The present invention relates to compound of formula (la) in the form of the Iaevorotatory isomer. The present invention relates to novel 1,3-dihydro-2H-indol-2-one derivatives, to a process for preparing them and to pharmaceutical compositions containing them. The compounds according to the present invention have affinity for and selectivity towards the V1b receptors or towards both the V1b and Vla receptors of arginine-vasopressin (AVP). AVP is a hormone which is known for its antidiuretic effect and its effect in regulating arterial pressure. It stimulates several types of receptor: V1 (V1a, Vlb) , V2 . These receptors are located in particular in the liver, the vessels (coronary, renal and cerebral), the platelets, the kidneys, the uterus, the adrenal glands, the pancreas, the central nervous system and the pituitary gland. AVP thus exerts cardiovascular, hepatic, pancreatic, antidiuretic and platelet-aggregating effects and effects on the central and peripheral nervous system, and on the uterine sphere. The location of the various receptors is described in: S. Jard et al., Vasopressin and oxytocin receptors: an overview, in Progress in Endocrinology. H. Imura and K. Shizurne ed., Experta Medica, Amsterdam, 1988, 1183-1188, as well as in the following articles: J. Lab. Clin. Med., 1989, 114,(6), 617-632 and Pharmacol. Rev., 1991, £3(1), 73-108. More particularly, the AVP V1a receptors are located in many peripheral organs and in the brain. They have been cloned in rats and man and they regulate most of the known effects of AVP: platelet aggregation; uterine contractions; the contraction of blood vessels; secretion of aldosterone, Cortisol, CRF (corticotropin-releasing factor) and adrenocorticotrophic hormone (ACTH); hepatic glycogenolysis, cell proliferation and the main central effects of AVP (hypothermia, memory, etc.). The V1b receptors were initially identified in the adenohypophysis of various animal species (rats, pigs, bovines, sheep, etc.) including man (S. Jard et al., Mol. Pharmacol., 1986, 3_0, 171-177; Y. Arsenijevic et al., J. Endocrinol., 1994, 141, 383-391; J. Schwartz et al., Endocrinology, 1991, 129(2), 1107-1109; Y. De Keyser et al., FEBS Letters, 1994, 356, 215-220) in which they stimulate the release of adrenocorticotrophic hormone via AVP and potentiate the effects of CRF on the release of ACTH (G.E. Gillies et al., Nature, 1982, 299, 355). In the hypothalamus, the V1b receptors also induce a direct release of CRF (Neuroendocrinology, 1994, 60, 503-508) and are, in :hese various respects, involved in stress situations. These V1b receptors have been cloned in rats, man and mice (Y. De Keyser, FEBS Letters, 1994, 356, 215-220; T. Sugimoto et al., J. Biol. Chem. 1994, 269 43), 27088-27092; M. Saito et al., Biochem. Biophys. Res. Commun., 1995, 212 (3), 751-757; S.J. Lolait et al. , Neurobiology, 1996, 92, 6783-6787; M.A. Ventura et al., Journal of Molecular Endocrinology, 1999, .22, 251-260) and various studies {in situ hybridization, PCR [polymerase chain reaction], etc.) reveal the ubiquitous presence of these receptors in various central tissues (brain, hypothalamus and adenohypophysis in particular) and peripheral tissues (kidney, pancreas, adrenals, heart, lungs, intestine, stomach, liver, mesentery, bladder, thymus, spleen, uterus, retina, thyroid, etc.) and in certain tumours (hypophyseal, pulmonary, etc.) suggesting a broad biological and/or pathological role for these receptors and a potential involvement in various diseases. By way of example, in rats, studies have shown that AVP regulates the endocrine pancreas, via the V1b receptors, by stimulating the secretion of insulin and glucagon (B. Lee et al., Am. J. Physiol. 269 (Endocrinol. Metab. 32): E1095-E1100, 1995) or the production of catecholamines in the medullo-adrenal which is the site of a local synthesis of AVP (E. Grazzini et al., Endocrinology, 1996, 137(a), 3906- 3914). Thus, in the latter tissue, AVP is thought to have a crucial role, via these receptors, in certain types of adrenal pheochromocytomas which secrete AVP and thereby induce a sustained production of catecholamines which are the cause of hypertension and which are resistant to angiotensin II-receptor antagonists and to conversion enzyme inhibitors. The adrenal cortex is also rich in V1a receptors involved in the production of glucocorticoids and mineralocorticoids (aldosterone and Cortisol). Via these receptors, AVP (in the circulation or synthesized locally) can induce a production of aldosterone with an efficacy which is comparable to that of angiotensin II (G. Guillon et al., Endocrinology, 1995, 136(3), 1285-1295). Cortisol is a powerful regulator of the production of ACTH, the stress hormone. Recent studies have also shown that the adrenal glands are capable of directly releasing CRF and/or ACTH via activation of the V1b and/or V1a receptors borne by the medullary cells (G. Mazzocchi et al., Peptides, 1997, 18(2), 191-195; E. Grazzini et al., J. Clin. Endocrinol. Metab., 1999, .84(6), 2195-2203). The V1b receptors are also considered as a label for ACTH-secreting tumours such as certain pituitary tumours, certain bronchial carcinomas (SCLC [small lung cell cancers]), pancreatic, adrenal and thyroid carcinomas, inducing Cusnmg's, syndrome in certain cases (J. Bertherat et al., Eur. J. Endocrinol., 1996, 135, 173; G.A. Wittert et al., Lancet, 1990, 335, 991-994; G. Dickstein et al. , J. Clin. Endocrinol. Metab., 1996, 81(8), 2934-2941). As regards the Vla receptors, they are a more specific label for small cell lung cancers (SCLC) (P.J. Woll et al., Biochem. Biophys. Res. Commun., 1989, 164 (1), 66-73). Thus, the compounds according to the present invention are obvious diagnostic tools and offer a novel therapeutic approach in the proliferation and detection of these tumours, even at an early stage (radiolabelling; SPECT [single photon emission computed tomography]; PET scan [positron emission tomography scanner]). The abundant presence of the V1b receptor messenger in the stomach and intrstine suggests an involvement of AVP via this receptor on the release of gastrointestinal hormones such as cholecystokinin, gastrin or secretin (T. Sugimoto et al., Molecular cloning and functional expression of V1b receptor gene, in Neurohypophysis: Recent Progress of Vasopressin and Oxytocin Research; T. Saito, K. Kurokawa and S. Yoshida ed., Elvesier Science, 1995, 409-413). 1,3-Dihydro-2H-indol-2-one derivatives have been described in certain patent applications as arginine-vasopressin receptor ligands and/or oxytocin receptor ligands: mention may be made of patent applications WO 93/15051, EP-A-0 636 608. Ep-A-0 636 609, WO 95/18105, WO 97/15556 and WO 98/25901. No non-peptide compound with affinity for and selectivity towards the V1b receptors or simultaneously for and towards both the V1b and V1a receptors of arginine-vasopressin is known to date. Novel 1,3-dihydro-2H-indol-2-one derivatives have now been found which have affinity for and selectivity towards the V1b receptors or for and towards both the V1b and V1a receptors of arginine-vasopressin. These compounds may be used for the preparation of medicinal products that are useful in the treatment or prevention of any pathology in which arginine-vasopressin and/or the V1b receptors or both the V1b receptors and the V1a receptors are involved, in particular in the treatment or prevention of complaints of the cardiovascular system, for example hypertension; of the central nervous system,, for example stress, anxiety, depression, compulsive obsessive disorder and panic attacks; of the renal system; of the gastric system as well as in the treatment of small cell lung cancers; of obesity; of type II diabetes; of insulin resistance; of hypertriglyceridemia; of atherosclerosis; of Cushing's syndrome; of any pathology following stress and chronic stress states. R* ■ in which: R1 represents a halogen atom; a (C1-C4) alkyl; a (C1-C4)alkoxy; a trifluoromethyl radical; a trifluoromethoxy radical; R2 represents a hydrogen atom; a halogen atom; a (C1-C4) alkyl; a (C1-C4) alkoxy; a trif luoromethyl radical; or R2 is in position -6- of the indol-2-one ring and R1 and R2 together represent a divalent trimethylene radical; R3 represents a halogen atom; a hydroxyl; a (C1-C2) alkyl; a (C1-C2) alkoxy; a trif luoromethoxy radical; R4 represents a hydrogen atom; a halogen atom; a (C1-C2).alkyl; a (C1-C2) alkoxy; or R4 is in position -3- of the phenyl and R3 and R4 together represent a methylenedioxy radical; R5 represents an ethylamino group; a dimethylamino group; an azetidin-1-yl radical; a (C1-C2) alkoxy; R6 represents a hydrogen atom; a (C1-C4) alkyl; a group - (CH2)n-CO-R9; a group -CO- (CH2)n-NR10Rn; R7 represents a (C1-C4) alkoxy; R8 represents a (C1-C4) alkoxy; R9 represents a hydroxyl; a (C1-C4)alkoxy; a group -NR12R13 ; R1o and R11 each independently represent a (C1-C4) alkyl; or R1o and Rn, together with the nitrogen atom to which they are attached, constitute a heterocyclic radical chosen from: azetidin-1-yl, pyrrolidin-1-yl, piperid-1-yl, piperazin-1-yl, morpholin-4-yl or thiomorpholin-4-yl; R12 represents a hydrogen or a (C1-C4) alkyl; R13 represents a (C1-C4} alkyl; a -C (CH3) 2CH2OH group; a -C(CH3) (CH2OH)2 group; a -C(CH2OH)3 group; or R12 and R13, together with the nitrogen atom to which they are attached, constitute a heterocyclic radical chosen from: azetidin-1-yl, pyrrolidin-1-yl, piperid-1-yl, piperazin-1-yl, morpholin-4-yl or thiomorpholin-4-yl; n is 1 or 2; as well as the solvates and/or hydrates thereof and the possible salts thereof with mineral or organic acids. The term "halogen atom" means a chlorine, bromine, fluorine or iodine atom. The terms "alkyl" and "alkoxy", respectively, mean a linear or branched alkyl radical or alkoxy radical, respectively. The compounds of formula (I) comprise at least 3 asymmetric carbon atoms, the carbon atom bearing the substituent COR5 has the (S) configuration, and the carbon atom bearing the substituent OR6 has either the (R) configuration or the (S) configuration. The optically pure isomers of the compounds of formula (I) and the mixtures thereof in all proportions form part of the invention. The salts are generally prepared with pharmaceutically acceptable acids, but the salts of other acids which are useful for purifying or isolating the compounds of formula (I) also form part of the invention. The pharmaceutically acceptable salts of the compounds of formula (I) are, for example, the hydrochloride, hydrobromide, sulphate, hydrogen sulphate, dihydrogen phosphate, methanesulphonate, benzenesulphonate, naphthalenesulphonate, para-toluenesulphonate, maleate, fumarate, succinate, citrate, acetate, gluconate or oxalate. According to the present invention, the compounds of formula (I) that are preferred are those in which: R1 represents a halogen atom; a (C1-C4) alkyl; a trifluoromethyl radical; a trifluoromethoxy radical; R2 represents a hydrogen atom; a halogen atom; a (C1-C4) alkyl; a (C1-C4) alkoxy; a trif luoromethyl radical; or R2 is in position -6- of the indol-2-one ring and R1 and R2.together represent a divalent trimethylene radical; R3 represents a halogen atom; a hydroxyl; a (C1-C2) alkoxy; R4 represents a hydrogen atom; a halogen atom; a (C1-C2) alkyl; a (C1-C2) alkoxy; or R4 is in position -3- of the phenyl and R3 and R4 together represent a methylenedioxy radical; R5 represents an ethylamino group; a dimethylamino group; an azetidin-1-yl group; a (C1-C2} alkoxy; R6 represents a hydrogen atom; a (C1-C4) alkyl; R7 represents a (C1-C4) alkoxy; R8 represents a (C1-C4) alkoxy; as well as the solvates and/or hydrates thereof and the possible salts thereof with mineral or organic acids. According to the present invention, the compounds of formula (I) in which R1 represents a chlorine atom, a methyl radical or a trifluoromethoxy radical are preferred. According to the present invention, the compounds of formula (I) in which R2 represents a hydrogen atom or is in position -6- of the indol-2-one and represents a chlorine atom, a methyl radical, a methoxy radical or a trifluoromethyl radical are preferred. According to the present invention, the compounds of formula (I) in which R3 represents a chlorine atom, a fluorine atom, a methoxy radical, an ethoxy radical or a trifluoromethoxy radical are preferred. According to the present invention, the compounds of formula (I) in which R4 represents a hydrogen atom or is in position -3- or -4- of the phenyl and represents a fluorine atom or a methoxy radical; or R4 is in position -3- of the phenyl and, together with R3, represent a methylenedioxy radical, are preferred. According to the present invention, the compounds of formula (I) in which R5 represents a dimethylamino group, an azetidin-1-yl radical or a methoxy radical are preferred. According to the present invention, the compounds of formula (I) in which R6 represents a halogen atom, a methyl radical, an ethyl radical, a tert-butoxycarbonylmethyl radical, a carboxymethyl radical, a [[2-hydroxy-l-(hydroxymethyl)- 1-methylethyl]amino]carbonylmethyl radical, a (1-piperazinyl)carbonylmethyl radical, a (4-morpholinyl)carbonylmethyl radical or a 3-(4-morpholinyl)propanoyl radical are preferred. According to the present invention, the compounds of formula (I) in which R7 is in position -2-or -3- of the phenyl and represents a methoxy radical are preferred. According to the. present invention, the compounds of formula (I) in which R8 represents a methoxy radical are preferred. According to the present invention, the compounds of formula (I) in the form of optically pure isomers are preferred. Particularly preferred are the optically pure isomers of the compounds of formula: in which R1, R2, R3, R4, R5, R6, R7 and R8 are as defined for a compound of formula (I), the carbon atom bearing substituent OR6 has the (R) configuration and the carbon atom in position 3 of the indol-2-one has either the (R) configuration or the (S) configuration. The laevorotatory isomer of the compounds of formula (Ia) is more particularly preferred. Most particularly preferred are the compounds of formula (Ia), laevorotatory isomer, in which: R1 represents a chlorine atom, a methyl radical or a trifluoromethoxy radical; R2 represents a hydrogen atom or is in position -6-of the indol-2-one and represents a chlorine atom, a methyl radical, a methoxy radical or a trifluoromethyl radical; R3 represents a chlorine atom, a fluorine atom, a methoxy radical or an ethoxy radical; R4 represents a hydrogen atom or is in position -3-or -4- of the phenyl and represents a fluorine atom or a methoxy radical; or R4 is in position -3- of the phenyl and, together with R3, represent a methylenedioxy radical; R5 represents a dimethylamino radical or a methoxy radical; R6 represents a hydrogen atom; a methyl radical; an ethyl radical; a tert-butyloxycarbonylmethyl radical; a carboxymethyl radical; a [[2-hydroxy-1-(hydroxymethyl) -1-methylethyl]amino]carbonylmethyl radical; a (1-piperazinyl)carbonylmethyl radical; a (4-morpholinyl) carbonylmethyl radical; a 3-(4-morpholinyl)propanoyl radical; - R7 is in position -2- of the phenyl and represents a methoxy radical; - R8 represents a methoxy radical; as well as the salts thereof with mineral or organic acids, and the solvates and/or hydrates thereof. The following compounds: - (2S, 4R)-l-[5-Chloro-l-[(2,4-dimethoxy- phenyl)sulphonyl]-3-(2-methoxyphenyl)-2-oxo- 2,3-dihydro-lH-indol-3-yl]-4-hydroxy-N,N-dimethyl-2-pyrrolidinecarboxamide, laevorotatory isomer; - (2S,4R)-l-[5-Chloro-l-[(2,4-dimethoxy¬ phenyl) sulphonyl]-3-(2-methoxyphenyl)-2-oxo- 2,3-dihydro-lH-indol-3-yl]-4-methoxy-N,N-dimethy1-2-pyrrolidinecarboxamide, laevorotatory isomer; - (2S, 4R)-l-[5-Chloro-3-(2-chlorophenyl)-L-[(2,4-dimethoxyphenyl)sulphonyl]-2-oxo-2,3-dihydro-LH-indol-3-yl]-4-hydroxy-N,N-dimethyl-2-pyrrolidine-rarboxamide, laevorotatory isomer; - (2S, 4R)-l-[5-Chloro-3-(2-chlorophenyl)- ■t -[(2,4-dimethoxyphenyl)sulphonyl]-6-methoxy-2-oxo-, 3-dihydro-lH-indol-3-yl] -4-methoxy-N,N-dimethyl--pyrrolidinecarboxamide, laevorotatory isomer; - (2S, 4R)-l-[5-Chloro-l~[(3,4~dimethoxy- henyl)sulphonyl]-3-(2-methoxyphenyl)-2-oxo- , 3-dihydro-lH-indol-3-yl] -4-hydroxy-N,N-dimethyl- 2-pyrrolidinecarboxamide, laevorotatory isomer; -Methyl (2S, 4R)-1-[5-chloro-3-(2-methoxy-phenyl)-1-[(3,4-dimethoxyphenyl)sulphonyl]-2-oxo-2, 3-dihydro-lH-indol-3-yl] -4-hydroxy-2-pyrrolidine-carboxylate, laevorotatory isomer; - (2S, 4R)-l-[5-Methyl-l-[(2,4-dimethoxy- phenyl)sulphonyl]-3-(2-methoxyphenyl)-2-oxo- 2, 3-dihydro-lH-indol-3-yl] -4-hydroxy-N,N-dimethyl-2-pyrrolidinecarboxamide, laevorotatory isomer; - (2S, 4R)-l-[5-Chloro-l-[(2,4-dimethoxy- phenyl)sulphonyl]-3-(2-methoxyphenyl)-2-oxo- 2,3-dihydro-lH-indol-3-yl]-2-(azetidin-1-ylcarbonyl)-4-hydroxypyrrolidinecarboxamide, laevorotatory isomer; - (2S, 4R)-l-[5-Trifluoromethoxy-l-[(2,4-dimethoxyphenyl) sulphonyl] -3- (2-methoxyphenyl) -2-oxo-2,3-dihydro-lH-indol-3-yl]-4-hydroxy-N,N-dimethyl-2-pyrrolidinecarboxamide, laevorotatory isomer; - (2S, 4R)-l-[5-Chloro-l-[(2,4-dimethoxy-phenyl)sulphonyl]-3-(2-methoxyphenyl)-6-methyl-2-oxo-2, 3-dihydro-lH-indol-3-yl] -4-hydroxy-N,N-dimethyl-2-pyrrolidinecarboxamide, laevorotatory isomer; - (2S, 4R)-l-[3-(2-Chlorophenyl)-l-[(2,4-dimethoxyphenyl)sulphonyl]-5,6-dimethyl-2-oxo- 2, 3-dihydro-lH-indol-3-yl] -4-hydroxy-N,N-dime thy1-2-pyrrolidinecarboxamide, laevorotatory isomer; - (2S, 4R)-l-[5-Chloro-l-[(2,4-dimethoxy- phenyl)sulphonyl]-3-(2, 3-dimethoxyphenyl)-2-oxo- 2,3-dihydro-lH-indol-3-yl]-4-methoxy-N,N-dimethyl-2-pyrrolidinecarboxamide, laevorotatory isomer; - (2S, 4R)-l-[5-Chloro-l-[(2,4-dimethoxy-phenyl)sulphonyl]-3-(2-methoxyphenyl)-6-trifluoro-methyl-2-oxo-2,3-dihydro-lH-indol-3-yl] -4-methoxy-N,N-dimethyl-2-pyrrolidinecarboxamide, laevorotatory isomer; - (2S, 4R)-l-[6-Chloro-l-[(2,4-dimethoxy-phenyl)sulphonyl]-3-(2-methoxyphenyl)-5-methyl-2-oxo-2, 3-dihydro-lH-indol-3-yl] -4-methoxy-N,N-dimethyl-2-pyrrolidinecarboxamide, laevorotatory isomer; - (2S, 4R)-l-[5-Chloro-l-[(2,4-dimethoxy-phenyl)sulphonyl]-3-(2-methoxyphenyl)-2-oxo- 2, 3-dihydro-lH-indol-3-yl] -4-ethoxy-N,N-dimethyl-2-pyrrolidinecarboxamide, laevorotatory isomer; - (2S, 4R)-l-[5-Chloro-l-[(2,4-dimethoxy- phenyl)sulphonyl]-3-(2,3-dimethoxyphenyl)-2-oxo- 2, 3-dihydro-lH-indol-3-yl] -4-hydroxy-N,N-dirnethyl-2-pyrrolidinecarboxamide, laevorotatory isomer; - (2S, 4R)-l-[5,6-Dichloro-3-(2-chlorophenyl)- 1-[(2,4-dimethoxyphenyl)sulphonyl]-2-oxo-2,3-dihydro- lH-indol-3-yl]-4-hydroxy-N,N-dimethyl-2-pyrrolidine- carboxamide, laevorotatory isomer; -Methyl (2S, 4R)-1-[5-chloro-1-[(2,4-dimethoxyphenyl)sulphonyl]-3-(2-methoxyphenyl)-2-oxo-2,3-dihydro-lH-indol-3-yl]-4-methoxy-2-pyrrolidinecarboxylate, laevorotatory isomer; -Methyl (2S, 4R) -1- [5-chloro-1-[(2,4-dimethoxyphenyl)sulphonyl]-3-(2-methoxyphenyl)-6-methyl-2-oxo-2,3-dihydro-lff-indol-3-yl]-4-methoxy-2-pyrrolidinecarboxylate, laevorotatory isomer; - (2S, 4R)-l-[5-Chloro-l-[(2,4-dimethoxy¬phenyl) sulphonyl]-3-(2-ethoxyphenyl)-2-oxo-2,3-dihydro-lff-indol-3-yl]-4-hydroxy-N,N-dimethyl-2-pyrrolidine-carboxamide, laevorotatory isomer; - (2S, 4R)-l-[5-Chloro-l-[(2,4-dimethoxy¬phenyl) sulphonyl]-3-(2 , 3-difluorophenyl)-2-oxo- 2, 3-dihydro-lH-indol-3-yl]-4-hydroxy-N,N-dimethyl-2-pyrrolidinecarboxamide, laevorotatory isomer; - (2S, 4R)-l-[5-Chloro-l-[(2,4-dimethoxy¬phenyl) sulphonyl]-3-(2 , 4-dimethoxyphenyl)-2-oxo-2,3-dihydro-1H-indol-3-yl]-4-hydroxy-N,N-dimethyl-2-pyrrolidinecarboxamide, laevorotatory isomer; - (2S, 4R)-l-[5-Chloro-l-[(2,4-dimethoxy¬phenyl) sulphonyl]-3-(1,3-benzodioxol-4-yl)-2-oxo-2, 3-dihydro-1H-indol-3-yl] -4-hydroxy-N,N-dimethyl-2-pyrrolidinecarboxamide, laevorotatory isomer; - (2S, 4R)-l-[5,6-Dichloro-l-[(2,4-dimethoxyphenyl)sulphonyl]-3-(2-methoxyphenyl)-2-oxo-2, 3-dihydro-lff-indol-3-yl] -4-hydroxy-N,N-dimethyl-2-pyrrolidinecarboxamide, laevorotatory isomer; - tert-Butyl 2-[[(3R, 5S)-1-[5-chloro-l-[(2, 4-dimethoxyphenyl)sulphonyl]-3-(2-methoxyphenyl)-2-oxo- 2, 3-dihydro-1H-indol-3-yl] -5- [ (dimethylamino) carbonyl] - 3-pyrrolidinyl]oxy]acetate, laevorotatory isomer; - 2-[[(3R, 5S)-l-[5-Chloro-l-[(2,4-dimethoxy- phenyl)sulphonyl]-3-(2-methoxyphenyl)-2-oxo- 2,3-dihydro-lH-indol-3-yl]-5-[(dimethylamino)carbonyl]-3-pyrrolidinyl]oxy]acetic acid, laevorotatory isomer; - (2S, 4R)-l-[5-Chloro-l-[(2,4-dimethoxy- phenyl)sulphonyl]-3-(2-methoxyphenyl)-2-oxo- 2,3-dihydro-lH-indol-3-yl]-4-[2-[[2-hydroxy- 1-(hydroxymethyl)-1-methylethyl]amino]-2-oxoethoxy]- N,N-dimethyl-2-pyrrolidinecarboxamide, laevorotatory isomer; - (2S, 4R)-l-[5-Chloro-l-[(2,4-dimethoxy- phenyl) sulphonyl]-3-(2-methoxyphenyl)-2-oxo- 2,3-dihydro-lH-indol-3-yl]-N,N-dimethyl-4-[2-oxo- 2- (1-piperazinyl) ethoxy] -2-pyrrolidinecarboxamide, laevorotatory isomer; - (2S, 4R)-l-[[(2,4-Dimethoxyphenyl)sulphonyl]-3-(2-methoxyphenyl)-2-OXO-2, 3-dihydro-lH-indol-3-yl]-N,N-dimethyl-4-[2-oxo-2-(4-morpholinyl)ethoxy]-2-pyrrolidinecarboxamide, laevorotatory isomer; - (3R, 5S)-l-[5-Chloro-l-[(2, 4-dimethoxy-phenyl) sulphonyl]-3-(2-methoxyphenyl)-2-oxo- 2, 3-dihydro-lH-indol-3-yl] -5- [ (dimethylamino) carbonyl] -3-pyrrolidinyl 3-(4-morpholinyl)propanoate, laevorotatory isomer; as well as the possible salts thereof with mineral or organic acids, and the solvates and/or hydrates thereof are more particularly preferred. According to another of its aspects, a subject of the present invention is a process for preparing compounds of formula (I), possible salts thereof with mineral or organic acids, and solvates and/or hydrates thereof, characterized in that: a compound of formula: in which R1, R2, R3, R4, R5 and R6 are as defined for a compound of formula (I), is reacted, in the presence of a base, with a halide of formula: in which R7 and R8 are as defined for a compound of formula (I) and Hal represents a halogen atom. The compound of formula (I) is optionally converted into a salt thereof with mineral or organic acids. The reaction is carried out in the presence of a strong base, for instance a metal hydride such as sodium hydride or an alkali metal alkoxide such as potassium tert-butoxide, in an anhydrous solvent such as N,N-dimethylformamide or tetrahydrofuran and at a temperature of between -70°C and +60°C. The reaction is preferably carried out using a compound of formula (III) in which Hal = C1. A compound of formula (I) in which R6 represents a (C1-C4)alkyl may also be prepared by reacting a compound of formula (I) in which R6 represents hydrogen with a (C1-C4)alkyl halide, in the presence of a base such as a metal hydride, in an inert solvent such as N,N-dimethylformamide or tetrahydrofuran according to the conventional methods. A compound of formula (I) in which R6 represents a group - (CH2)n-CO-R9 in which R9 represents a hydroxyl is preferably prepared by hydrolysing a compound of formula (I) in which R6 represents a group - (CH2)n-CO-R9 in which R9 represents a tert-butyloxy, in acidic medium, using a strong acid such as trifluoroacetic acid or hydrochloric acid in a solvent such as dichloromethane or dioxane and at a temperature of between 0°C and room temperature. A compound of formula (I) in which R6 represents a group -(CH2)n-CO-R9 in which R9 represents a group -NR12R13 is preferably prepared by reacting a compound of formula (I) in which R9 represents a hydroxyl with an amine of formula H-NR12R13 according to the conventional methods of peptide coupling. The compounds of formula (I) thus obtained may be subsequently separated from the reaction medium and purified according to the conventional methods, for example by crystallization or chromatography. The compounds of formula (I) thus obtained are isolated in free base or salt form, according to the conventional techniques. When the compounds of formula (I) are obtained in free base form, the salification is carried out by treatment with the selected acid in an organic solvent. By treating the free base, dissolved, for example, in an ether such as diethyl ether or in an alcohol such as 2-propanol or in acetone or in dichloromethane, or in ethyl acetate or in acetonitrile, with a solution of the selected acid in one of the abovementioned solvents, the corresponding salt is obtained, which is isolated according to the conventional techniques. Thus, the hydrochloride, hydrobromide, sulphate, trifluoroacetate, hydrogen sulphate, dihydrogen phosphate, methanesulphonate, oxalate, maleate, succinate, fumarate, 2-naphthalenesulphonate, benzenesulphonate, para-toluenesulphonate, gluconate, citrate or acetate is prepared, for example. At the end of the reaction, the compounds of formula (I) may be isolated in the form of a salt thereof, for example the hydrochloride or oxalate; in this case, if necessary, the free base may be prepared by neutralizing the said salt with a mineral or organic base, such as sodium hydroxide or triethylamine or with an alkali metal carbonate or bicarbonate, such as sodium or potassium carbonate or bicarbonate. The compounds of formula (II) are prepared by reacting a 3-halo-l,3-dihydro-2H-indol-2-one compound of formula: in which R1, R2, R3 and R4 are as defined for a compound of formula. (I) and Hal represents a halogen atom, preferably chlorine or bromine, with a compound of formula: in which R5 and R6 are as defined for a compound of formula (I). The reaction is carried out in the presence of a base such as diisopropylethylamine or triethylamine, in an inert solvent such as dichloromethane or tetrahydrofuran or a mixture of these solvents and at a temperature of between room temperature and the reflux temperature of the solvent. The compounds of formula (III) are known or prepared by known methods such as those disclosed in EP-B-0 469 984 and WO 95/18105. For example, the compounds of formula (III) may be prepared by halogenating the corresponding benzenesulphonic acids or salts thereof, for example the sodium or potassium salts thereof. The reaction is carried out in the presence of a halogenating agent such as phosphorus oxychloride, thionyl chloride, phosphorus trichloride, phosphorus tribromide or phosphorus pentachloride, without solvent or in an inert solvent such as a halogenated hydrocarbon or N,N-dimethylformamide and at a temperature of between -10°C and 2 00°C. 2,4-Dimethoxybenzenesulphonyl chloride is prepared according to J. Am. Chem. Soc., 1952, 74, 2008. 3,4-Dimethoxybenzenesulphonyl chloride is commercially available or is prepared according to J. Med. Chem., 1977, 20(10), 1235-1239. The compounds of formula (IV) are known and are prepared according to known methods such as those disclosed in WO 95/18105. For example, a compound of formula: (VI) in which R1, R2, R3 and R4 are as defined for a compound of formula (I), is converted into a compound of formula (IV) in which Hal = Cl by the action of thionyl chloride in the presence of a base such as pyridine, in an inert solvent such as dichloromethane and at a temperature of between 0°C and room temperature. According to another example for preparing the compounds of formula (IV), a compound of formula: in which R1, R2, R3 and R4 are as defined for a compound of formula (I), is converted into a compound of formula (IV) by means of a halogenating agent such as bromine, according to the process disclosed in Farm. Zh.(Kiev), 1976, 5, 30-33. The compounds of formula (VI) are known and are prepared according to known methods such as those disclosed in WO 95/18105. For example, a compound of formula (VI) is prepared by reacting a lH-indole-2,3-dione derivative of formula: (VIII) in which R1 and R2 are as defined for a compound of formula (I), with an organomagnesium derivative of formula: MgHal (IX) in which R3 and R4 are as defined for a compound of formula (I) and Hal represents a halogen atom, preferably bromine or iodine, in an inert solvent such as tetrahydrofuran or diethyl ether. It is also possible to prepare a compound of formula (VI) in which R3 is as defined for a compound of formula (I) and R4, which is other than hydrogen, is in position -3- or -6- of the phenyl, by reacting a compound of formula: (XVII) in which R3 is as defined for a compound of formula (I) and R4 is in position -2- or -5- of the phenyl, with a lithium derivative such as n-butyllithium, and the lithiated intermediate thus obtained is then reacted with a compound of formula (VIII). The reaction is carried out in a solvent such as diethyl ether, tetrahydrofuran or hexane or a mixture of these solvents, at a temperature of between -7 0°C and room temperature. The lH-indole-2,3-dione derivatives (VIII) are commercially available or are prepared according to the methods disclosed in Tetrahedron Letters, 1998, 3_9, 7679-7682; Tetrahedron Letters, 1994, 35, 7303-7306; J. Org. Chem., 1977, 42(8), 1344-1348; J. Org. Chem., 1952, 17, 149-156; J. Am. Chem. Soc. , 1946, 68, 2697-27 03; Organic Syntheses, 1925, V, 71-74 and Advances in Heterocyclic Chemistry, A.R. Katritzky and A.J. Boulton, Academic Press, New York, 1975, 18, 2-58. The organomagnesium derivatives (IX) are prepared according to the conventional methods that are well known to those skilled in the art. The compounds of formula (XVII) are known or prepared according to known methods. A compound of formula (VI) may also be prepared by air-oxidation of a compound of formula (VII) in the presence of a base such as sodium hydride and in the presence of dimethyl disulphide. In particular, the compounds of formula (VI) in which R3 = (C1-C2) alkoxy and R4 = H, or R3 = R4 = (Ci-C2)alkoxy with R4 in position -3 or -6 of the phenyl, R2 is other than a halogen atom and Ri is as defined for a compound of formula (I), may be prepared by following the process described in Scheme 1. Scheme 1 In step al of Scheme 1, a compound of formula (X) is first reacted with a lithium derivative such as n-butyllithium, in the absence or presence of a base such as N,N,N',N'-tetramethylenediamine, and the lithiated intermediate thus obtained is then reacted with diethyl oxalate to give the compound of formula (XI). The reaction is carried out in an inert solvent such as diethyl ether, tetrahydrofuran or hexane or a mixture of these solvents and at a temperature of between -70°C and room temperature. In step bl, a compound of formula (XII) is first reacted with two equivalents of a lithium 5 derivative such as tert-butyllithium, and the lithiated intermediate thus obtained is then reacted with the compound of formula (XI) to give the expected compound of formula (VI). The reaction is carried out in an inert solvent such as diethyl ether, tetrahydrofuran or 3 pentane or a mixture of these solvents and at a temperature of between -70°C and room temperature. The compounds of formula (X) are commercially available or synthesized conventionally. The compounds of formula (XII) are prepared i by reacting the corresponding aniline derivatives with di-tert-butyl dicarbonate according to the conventional methods. The compounds of formula (VII) are known and are prepared according to known methods such as those disclosed in WO 95/18105 or in J. Org. Chem., 1968, 33 1640-1643. The compounds of formula (V) in which R5 represents a (C1-C2)alkoxy and R6 = H are commercially available. The compounds of formula (V) in which R5 represents a (C1-C2) alkoxy and R6 = (C1-C4)alkyl are known or are prepared according to known methods such as those disclosed in J. Med. Chem. , 1988, 31 875-885 starting with (2S, 4R)- or (2S, 4S)-4-hydroxy-pyrrolidine-2-carboxylic acid protected on the nitrogen atom of the pyrrolidine. The compounds of formula (V) in which R5 is an ethylamino or dimethylamino group or an azetidin-1-yl radical and R6 = H or (Cl-C4)alkyl are prepared according to Scheme 2 below in which Pr represents an N-protecting group, in particular benzyloxycarbonyl or tert-butoxycarbonyl. Scheme 2 In step a2 of Scheme 2, the nitrogen atom of the 4(R)- or 4(S)-hydroxy-(S)-proline is protected according to the conventional methods to obtain a compound of formula (XIII). The acid (XIII) is reacted in step b2 with ethylamine, dimethylamine or azetidine according to the conventional methods of peptide coupling to give the compound (XIV), which is deprotected, according to the known methods, to give a compound of formula (V) in which R6 = H. In step d2, the compound (XIV) may be reacted with a (C1-C4)alkyl halide, in the presence of a base such as a metal hydride or an alkali metal carbonate or alkaline-earth metal carbonate such as K2CO3 or Cs2C03, in an inert solvent such as tetrahydrofuran or N,N-dimethylformamide and at a temperature of between 0°C and the reflux temperature of the solvent, to give a compound (XV). It is also possible to carry out the reaction of a compound (XIV) with a (C1-C4)alkyl halide under conditions of phase-transfer catalysis, in the presence of a base such as an alkali metal hydroxide, for example sodium hydroxide, and of a phase-transfer catalyst such as a substituted quaternary ammonium salt, for example tetrabutylammonium hydrogen sulphate, in an inert solvent such as dichloromethane or benzene as a mixture with water. Deprotection of the N-protecting group of compound (XV) gives, in step e2 the compounds of formula (V) in which R6 = (C1-C4) alkyl. Alternatively, in step f2, the hydroxyl of compound (XIII) is alkylated by reaction with a (C1-C4)alkyl halide under the conditions of step d2, and the acid (XVI) thus obtained is reacted in step g2 with ethylamine, dimethylamine or azetidine according to the conventional methods of peptide coupling to give compound (XV). (2S, 4R)- and (2S, 4S)-4-hydroxypyrrolidine-2-carboxylic acid are commercially available. The compounds of formula (V) in which R5 represents an ethylamino group, a dimethylamino group, an azetidin-1-yl radical or a (Ci-C2) alkoxy and R6 = - (CH2)n-CO-R9 in which n is 1 or 2 and R9 represents a (C1-C4)alkoxy are prepared according to Scheme 3 below in which Pr represents an N-protecting group, in particular benzyloxycarbonyl or terfc-butoxycarbonyl. Scheme 3 HO. R„CO(CH,)nCL R9CO(CH,)no (R) or (S)7 \(S) (R) or (S)J~^ {$) 260°C. αD25= +219.4° (c = 0.103; chloroform) the more polar, isomer B: compound of Preparation 3.28, to give 0.661 g which is used without further purification. Preparations 3.29 and 3.30 Methyl (2S,4R)-1-[5-chloro-3-(2- methoxyphenyl)-2-oxo-2,3-dihydro-lH-indol-3-yl]-4- hydroxy-2-pyrrolidinecarboxylate, isomer A and isomer B (II) : R1 - C1; R2 = H; R3 = OCH3; R4 = H; R5 = OCH3; R6 = H 4 ml of DIPEA and then 1.64 g of methyl (2S,4R)-4-hydroxy-2-pyrrolidinecarboxylate hydrochloride are added, at RT, to a mixture of 1.4 g of the compound obtained in Preparation 1.1 in 20 ml of DCM, and the mixture is stirred for 12 hours at RT. The reaction mixture is concentrated under vacuum, the residue is extracted with EtOAc, the organic phase is washed with 5% K2C03 solution, with water, with saturated NaCl solution and dried over sodium sulphate, and the solvent is evaporated off under vacuum. The residue is chromatographed on silica gel, eluting with a DCM/MeOH mixture (97/3; v/v). The two isomers are separated: the less polar isomer, isomer A: compound of Preparation 3.29, to give 0.3 g; m.p. = 234-235°C αD25= +143.3° (c= 0.136; chloroform); the more polar isomer, isomer B: compound of Preparation 3.30, which is recrystallized from a DCM/iso-ether/hexane mixture to give 1.1 g αD25 = -199.1° (c = 0.112; chloroform). Preparation 3.31 Methyl (2S,4R)-l-[5-chloro-3-(2-methoxy-phenyl)-6--methyl-2-oxo-2,3-dihydro-lH-indol-3-yl]-4-hydroxy-2-pyrrolidinecarboxylate, mixture of the two diastereoisomers (II) : R1 = C1; R2 = 6-CH3; R3 = 0CH3; R4 = H; R5 = OCH3; R6 = H The solution of the compound obtained in Preparation 1.5 in DCM is concentrated under vacuum, the residue is taken up in a mixture of 20 ml of THF and 10 ml of DCM, 0.715 g of methyl (2S,4R)-4-hydroxy-2-pyrrolidinecarboxylate hydrochloride is added, at RT, followed by 0.8 g of triethylamine, and the mixture is stirred for 48 hours at RT. The reaction mixture is concentrated under vacuum, the residue is extracted with" DCM," the organic phase is washed with water and dried over Na2S04, and the solvent is evaporated off under vacuum. The residue is chromatographed on silica gel, eluting with a DCM/EtOAc mixture (50/50; v/v). 1.8 g of a mixture of the two diastereoisomers are obtained. Preparation 3.32 (2S,4S)-1-[5-Chloro-3-(2-methoxyphenyl)-2-oxo-2, 3-dihydro-lH-indol-3-yl] -4-hydroxy-N,N-dimethyl-2-pyrrolidinecarboxamide, mixture of the two diastereoisomers (II) : R1 = C1; R2 = H; R3 = OCH3; R4 = H; R5 = N(CH3)2; R6 = H A mixture of 4.6 g of the compound obtained in Preparation 2.5 in 50 ml of DCM is cooled to 4°C, 2.7 g of the compound obtained in Preparation 1.1 and then 5 ml of triethylamine are added and the mixture is stirred for 48 hours at RT. The reaction mixture is concentrated under vacuum, the residue is extracted with EtOAc, the organic phase is washed with 5% Na2CO3 solution, with saturated NaCl solution and dried over Na2S04, and the solvent is evaporated off under vacuum. The residue is chromatographed on alumina, eluting with a DCM/MeOH mixture (98/2; v/v). 1.6 g of a mixture of the two diastereoisomers are obtained. Preparation 3.33 (2S,4R)-1-[5-Chloro-3-(2-ethoxyphenyl)-2-oxo-2,3- dihydr o - 1H- ihdo 1 - 3 -y 1 ] - 4-hydroxy-N,N- dimethy1-2-pyrrolidinecarboxamide) laevorotatory isomer (II): R1 = C1; R2 = H; R3 = OCH2CH3; R4 = H; R5 = N(CH3)2; R6 = H 1.38 g of the compound obtained in Preparation 2.1 a) and then 1.46 g of DIPEA are added bo a solution of 2 g of the compound obtained in Preparation 1.12 in 20 ml of DCM, and the mixture is stirred for 12 hours at RT. The reaction mixture is concentrated under vacuum, the residue is extracted with EtOAc, the organic phase is washed with 5% K2C03 solution and dried over Na2S04, and the solvent is evaporated off under vacuum. The residue is chromatographed on alumina, eluting with a DCM/MeOH mixture (95/5; v/v). The two diastereoisomers are separated and the more polar compound is collected and re-chromatographed on silica gel, eluting with a DCM/EtOAc mixture (60/40; v/v) and then with DCM/MeOH (94/6; v/v). 0.726 g of the expected product is obtained. Preparations 3.34 and 3.35 (2S,4R)-1-[5-Chloro-3-(2-trifluoromethoxy-phenyl) -2-oxo-2, 3-dihydro-lH-indol-3-yl] -4-hydroxy-N,N-dimethyl-2-pyrrolidinecarboxamide, isomer A and isomer B (II) : R1 = C1; R2 = H; R3 = OCF3; R4 = H; R5 = N(CH3)2; R6 = H A mixture of 1.6 go f the compound obtained in Preparation 1.13, 0.8 g of the compound obtained in Preparation 2.1 a) and 1 ml of DIPEA in 20 ml of DCM is stirred for 24 hours at RT. The precipitate formed, corresponding to isomer A, which is the less polar compound on silica gel, DCM/MeOH (98/2; v/v) (compound of Preparation 3.34), is spin-filtered off. The spin-filtration liquors are placed at 0°C for 48 hours and the precipitate formed, again corresponding to isomer A, is spin-filtered off. The spin-filtration liquors are washed with water, the organic phase is dried over Na2S04 and the solvent is evaporated off under vacuum. The residue is chromatographed on silica gel, eluting with a DCM/MeOH mixture (98/2; v/v). The other isomer is separated out: - the more polar, isomer B: compound of Preparation 3.35, to give 0.2 g. Preparations 3.3 6 and 3.37 (2S,4R)-l-[5-Chloro-3-(2,3-difluorophenyl) 2-0x0-2,3-dihydro-lH-indol-3-yl]-4-hydroxy-N,N-dimethyl-2-pyrrolidinecarboxamide, isomer A and isomer B (II) : R1 = C1; R2 = H; R3 = F; R4 = 3-F; R5 = N(CH3)2; R6 = H A mixture of 0.4 g of the compound obtained in Preparation 1.14, 0.3 g of the compound obtained in Preparation 2.1 a) and 0.45 g of DIPEA in 20 ml of DCM is stirred for 2 "hours" at RT. The precipitate formed, corresponding to isomer A, which is the less polar compound on alumina, DCM/MeOH (98/2; v/v) (compound of Preparation 3.36), is spin-filtered off. The spin-filtration liquors are concentrated under vacuum, the residue is taken up in an EtOAc/acetone mixture, the resulting mixture is left for 12 hours under cold conditions, and the precipitate, again corresponding to isomer A, is spin-filtered off. The spin-filtration liquors are washed with water, the organic phase is dried over Na2SO4 and the solvent is evaporated off under vacuum. The residue is chromatographed on alumina, eluting with a DCM/MeOH mixture (98/2; v/v) . The other isomer is separated out: the more polar, isomer B: compound of Preparation 3.37, to give 0.1 g. αD25= -231° (c = 0.16; chloroform). Preparations 3.38 and 3.39 (2S,4R)-1-[5-Chloro-3-(2,4-dimethoxyphenyl)-2-oxo-2,3-dihydro-lH-indol-3-yl]-4-hydroxy-N,N-dimethyl-2-pyrrolidinecarboxaird.de, isomer A and isomer B (II): R1 = C1; R2. = H; R3 = 0CH3; R4 = 4-OCH3; R5 = N(CH3)2; R6 = H 1.5 g of the compound obtained in Preparation 2.1 a) are added to a solution of the compound obtained in Preparation 1.15 and 1 ml of triethylamine in 20 ml of "DCM, and this mixture is stirred Tor 1 hour at RT. The reaction mixture is washed twice with water, the organic phase is dried over Na2S04 and the solvent is evaporated off under vacuum. The residue is chromatographed on alumina, eluting with DCM and then with a DCM/MeOH mixture (98.2; v/v). The two isomers are separated: the less polar, isomer A: compound of Preparation 3.38 the more polar, isomer B: compound of Preparation 3.39, to give 0.26 g αD25 = -157° (c = 0.15; chloroform). Preparation 3.40 (2S,4R)-1-[5-Chloro-3-(1,3-benzodioxol-4-yl)-2-OXO-2,3-dihydro-lH-indol-3-yl]-4-hydroxy-N,N-dimethyl-2-pyrrolidinecarboxamide, laevorotatory isomer (II): R1 = C1; R2 = H; R3 + R4 = 2, 3-0-CH2-0-; R5 = N(CH3)2; R6 = H A mixture of 1.7 g of the compound obtained in Preparation 1.16, 0.9 g of the compound obtained in Preparation 2.1 a) and 1 ml of DIPEA in 20 ml of DCM is stirred for 2 hours at RT. The reaction mixture is washed with water, the organic phase is dried over Na2S04 and the solvent is evaporated off under vacuum. The residue is chromatographed on alumina, eluting with a DCM/MeOH mixture (97/3; v/v). The two diastereoisomers are separated out and the more polar compound is collected. 0.42 g of the expected product is obtained. αD25 = -108° (c =0.12; chloroform). Preparations 3.41 and 3.42 (2S,4R)-1-[5,6-Dichloro-3-(2-methoxyphenyl)-2-oxo-2,3-dihydro-lH-indol-3-yl]-4-hydroxy-N,N-dimethyl-2-pyrrolidinecarboxamide, isomer A and isomer B (II) : R1 = C1; R2 = 6-C1; R3 = 0CH3; R4 = H; R5 = N(CH3)2; R6 = H A mixture of 1.57 g of the compound obtained in Preparation 1.17, 1.45 g of the compound obtained in Preparation 2.1 a) and 0.8 ml of DIPEA in 15 ml of DCM is stirred for 1 hour 3 0 minutes at RT. The precipitate formed, corresponding to isomer A, which is the less polar compound on silica gel, DCM/MeOH (94/6; v/v), is spin-filtered off. The spin-filtration liquors are concentrated under vacuum, the residue is extracted with EtOAc, the organic phase is washed with 5% K2C03 solution, with water, with saturated NaCl solution and dried over Na2S04, and the solvent is evaporated off under vacuum. The residue is chromatographed on silica gel, eluting with the DCM/MeOH mixture (94/6; v/v). The two isomers are separated: the less polar, isomer A: compound of Preparation 3.41, which is crystallized from an iso-ether/MeOH mixture to give 0.295 g; m.p; = 261-262°C ΑD25=+113 .8° (c = 0.12; chloroform) the more polar, isomer B: compound of Preparation 3.42, to give 0.74 g. Preparations 3.43 and 3.44 tert-Butyl 2- [ [(3R, 5S) -1- [5-chloro-3- (2- methoxyphenyl)-2-oxo-2,3-dihydro-lH-indol-3-yl]-5- [ (dimethylamino)carbonyl)-3-pyrrolidinyl]oxy]acetate, isomer A and isomer B (II) : R1 = C1; R2 = H; R3 = OCH3; R4 = H; R5 = N(CH3)2; R6 = -CH2COOC(CH3)3 200 ml of THF, 1.87 g of triethylamine and then 4.5 g of the compound obtained in Preparation 1.1 are added to the solution of the compound obtained in Preparation 2.6 and the mixture is refluxed for 48 hours. The product is concentrated under vacuum and the residue is chromatographed on silica gel, eluting with a DCM/MeOH mixture (96/4; v/v). The isomers are separated: the less polar, isomer A: compound of Preparation 3.43, to give 1 g the more polar, isomer B: compound of Preparation 3.44, to give 3 g in the form of an oil. αD25 = -154° (c = 0.37; chloroform). Preparation 3.45 (3R,5S)-1-[5-Chloro-3-(2-methoxyphenyl)-2-oxo-2,3-dihydro-lH-indol-3-yl]-5-[(dimethylamino)-carbonyl]-3-pyrrolidinyl 3-(4-morpholinyl)propanoate, mixture of the two diastereoisomers (II): R1 = C1; R2 = H ; R3 = OCH3; R4 = H ; R5 = -N(CH3)2 . R6 = -CO-CH2CH,- N O A solution of 3 g of the compound obtained in Preparation 1.1 in 100 ml of THF is added to the solution of the compound obtained in Preparation 2.7 in EtOAc, and the mixture is stirred for 4 days at RT. The reaction mixture is concentrated under vacuum, the residue is extracted with EtOAc, the organic phase is washed with water and dried over Na2SO4, and the solvent is evaporated off under vacuum. The residue is chromatographed on silica gel, eluting with a DCM/MeOH mixture (92/8; v/v). 4.2 g of the expected product are obtained in the form of a foam. EXAMPLE 1 (2S,4R)-1-[5-Chloro-l-[(2,4-dimethoxyphenyl)-sulphonyl] -3- (2-methoxyphenyl) -2-oxo-2, 3-dihydro-lH-indol-3-yl]-4-hydroxy-N,N-dimethyl-2-pyrrolidine-carboxamide, laevorotatory isomer, 0.25 iso-ether (I) : R1 = C1; R2 = H; R3 = 0CH3; R4 = H; R5 = N(CH3)2; R6 = H; R7 = 2-OCH3; R8 = OCH3 A mixture of 0.67 g of the compound obtained in Preparation 3.2 (isomer B) in 10 ml of DMF is cooled to 0°C, under an argon atmosphere, 0.069 g of 60% sodium hydride in oil is added and the mixture is stirred until the evolution of gas has ceased. 0.404 g of 2,4-dimethoxybenzenesulphonyl chloride is then added and the mixture is stirred for 3 hours at RT. The reaction mixture is poured into 5 % K2CO3 solution and extracted with EtOAc, the organic phase is washed with water, with saturated NaCl solution and dried over Na2S04, and the solvent is evaporated off under vacuum. The residue is chromatographed on alumina, eluting with a DCM/MeOH mixture (99/1; v/v). 0.565 g of the expected product is obtained after crystallization from a DCM/iso-ether mixture. αD25 = -200°C (c = 0.26; chloroform). 1H NMR: DMS0-d6 + TFA, 360 K: δ (ppm) : 1.6: mt: 2H; 2.1 to 3.1: m: 8H; 3.35: s: 3H; 3.7: s: 3H; 3.9: s: 3H; 4.4: mt: 1H; 4.6: mt: 1H; 6.6 to 8.1: m: 10H. EXAMPLE 2 (2S,4R)-l-[5-Chloro-l-[(2,4-dimethoxyphenyl) sulphonyl]-3-(2-methoxyphenyl)-2-oxo-2,3-dihydro-lH-indol-3-yl]-4-methoxy-N,N-dimethyl-2-pyrrolidine-carboxamide, laevorotatory isomer (I) : R1 = C1; R2 = H; R3 = OCH3; R4 = H; R5 = N(CH3)2; Re = H; R7 = 2-OCH3; R8 = OCH3 0.04 g of 60% sodium hydride in oil is added, at RT and under an argon atmosphere, to a solution of 0.559 g of the compound obtained in Example 1 in 6 ml of DMF, and stirring is continued until the evolution of gas has ceased. 0.11 ml of methyl iodide is then added and the mixture is stirred for 24 hours at RT. A further 0.04 g of 60% sodium hydride in oil is added, foTldwed by 0.33 ml of methyl iodide, with stirring for 3 days at RT'. The reaction mixture is poured into water and extracted with EtOAc, the organic phase is washed with water, with saturated NaCl solution and dried over Na2S04, and the solvent is evaporated off under vacuum. The residue is chromatographed on silica gel, eluting with a DCM/MeOH mixture (98/2; v/v). 0.082 g of the expected product is obtained after crystallization from a DCM/iso-ether mixture; m.p. = 189-191°C. EXAMPLE 3 (2S,4R)-1-[5-Chloro-3-(2-chlorophenyl)-1- [ (2,4-dimethoxyphenyl)sulphonyl]-2-oxo-2,3-dihydro-lH- indol-3-yl]-4-hydroxy-N,N-dimethyl-2-pyrrolidinecarboxamide, laevorotatory isomer (I): R1 = C1; R2 = H; R3 = Cl; R4 = H; R5 = N(CH3)2; R6 = H; R7 = 2-OCH3; R8 = OCH3 A mixture of 0.567 g of the compound obtained in Preparation 3.4 (isomer B) in 5.5 ml of DMF is cooled to 0°C, under an argon atmosphere, 0.062 g of 60% sodium hydride in oil is added and the mixture is stirred for 10 minutes. 0.338 g of 2,4-dimethoxybenzenesulphonyl chloride is then added and the mixture is stirred for 3 hours at RT. Water is added to the reaction mixture, the resulting mixture is extracted three times with EtOAc, the combined organic phases are washed with saturated NaCl solution and dried over Na2S04, and the solvent is evaporated off jnder vacuum. The residue is chromatographed on silica gel, eluting with a DCM/MeOH mixture (98/2; v/v). 3.647 g of the expected product is obtained after :rystallization from iso-ether; m.p. = 254-256°C. αD25= -250° (c = 0.142; chloroform). EXAMPLE 4 (2S,4R)-1-[5-Chloro-3-(2-chlorophenyl)-[ (2,4-dimethoxyphenyl)sulphonyl]-6-methoxy-2-oxo-3-dihydro-lH-indol-3-yl]-4-methoxy-N,N-dimethyl- 2-pyrrolidinecarboxamide, laevorotatory isomer (I): R1 = C1; R2 - 6-OCH3; R3 = CI; R4 = H; R5 = N(CH3)2; R6 = H; R7 = 2-OCH3; R8 = OCH3 0.072 g of 60% sodium hydride in oil is added at RT, under an argon atmosphere, to a suspension of 0.719 g of the compound obtained in Preparation 3.20 (isomer B) in 7 ml of DMF, and the mixture is stirred until the evolution of gas has ceased. 0.390 g of 2,4-dimethoxybenzenesulphonyl chloride is then added and the mixture is stirred for 3 hours at RT. The reaction mixture is poured into 5% K2CO3 solution and extracted with EtOAc and then with DCM, the organic phases are washed separately with water, dried over Na2S04 and combined, and the solvents are partially concentrated under vacuum to the point of crystallization. The precipitate formed is spin-filtered off to give 0.735 g of the expected product; m.p. = 283-288°C. ΑD25 = -266.3° (c =.0.11; chloroform). EXAMPLE 5 (2S,4R)-1-[5-Chloro-l-[(3,4-dimethoxyphenyl)-sulphonyl] -3- (2-methoxypheriyl) -2-oxo-2 , 3-dihydro-lH-indol-3-yl]-4-hydroxy-N,N-dimethyl-2-pyrrolidine-carboxamide, laevorotatory isomer (I) : R1 = C1; R2 = H; R3 = OCH3; R4 = H; R5 = N(CH3)2; R6 = H; R7 = 2-OCH3; R8 = OCH3 A solution of 0.043 g of the compound octainea in preparation 3.2 (isomer B) in 1 ml of THF is cooled to -30oC under a nitrogen atmosphere, a solution of 0.22 g of potassium tert-butoxide in 1 ml of THF is added and the mixture is stirred for 15 minutes while allowing the temperature to rise to 0°C. A solution of 0.035 g of 3,4-dimethoxybenzene-sulphonyl chloride in i ml of THF is then added with stirring, while allowing the temperature to return to RT, and the mixture is then heated at 30°C for 2 hours 15 minutes. 0.1 g of PS-Trisamine is added and the mixture is stirred for 1 hour 15 minutes at RT. 1 ml of DCM and 1 ml of water are added with stirring, the aqueous phase is then removed by filtration through a Whatman FT 5.0 μ PTFE filter and the organic phase is concentrated under vacuum. The residue is chromatographed on silica gel, eluting with DCM and then with a DCM/EtOAc mixture of from (90/10; v/v) to (70/30; v/v) and finally with a DCM/MeOH mixture of from (99/1; v/v) tO (96/4; v/v). 0.026 g of the expected product is obtained. MH+ = 629. EXAMPLE 6 Methyl (2s,4R)-1-[5-chloro-3-(2-methoxy-phenyl)-1-[(3,4-dimethoxyphenyl)sulphonyl]-2-oxo-2., 3-dihydro-lH-indo1-3-ylJ -4-hydroxy-2-pyrrolidinecarboxylate, laevorotatory isomer (I) : R1 = cl; R2 = H; R3 = 0CH3; R4 = H; R5 = OCH3; R6 = H; R7 = 3-OCH3; R8 = OCH3 A mixture of 0.477 g of the compound obtained in Preparation 3.30 (isomer B) in 4.7 ml of DMF is cooled to 0°C under an argon atmosphere, 0.055 g of 60% sodium hydride in oil is added and the mixture is stirred for 10 minutes. 0.297 g of 3,4-dimethoxy- benzenesulphonyl chloride is then added, and the mixture is stirred for 3 hours 30 minutes at RT. Water is added to the reaction mixture, the resulting mixture is extracted three times with EtOAc, the combined organic phases are washed with water, with saturated NaCl solution and dried over Na2SO4, and the solvent is evaporated off under vacuum. The residue is chromatographed on silica gel, eluting with a DCM/MeOH mixture (97/3; v/v). 0.3 g of the expected product is obtained after crystallization from a DCM/iso-ether mixture. .=_ 139 .10 (c = 0.115; chloroform) . EXAMPLES 7 and 8 (2S,4S)-1-[5-Chloro-l-[(2,4-dimethoxyphenyl) sulphonyl]-3-(2-methoxyphenyl)-2-oxo-2,3-dihydro-ltf-Lndol-3-yl]-4-hydroxy-N,N-dimethyl-2-pyrrdlidine-narboxamide, laevorotatory isomer and dextrorotatory Isomer (I) : Ri = CI; R2 = H; R3 = OCH3; R4 = H; l5 = N(CH3)2; Re = H; R7 = 2-OCH3; R8 = OCH3 A mixture of 0.82 g of the compound obtained in Preparation 3.32 (mixture of diastereoisomers) in 5 ml of DMF is cooled to 4°C, under a nitrogen atmosphere, 0.076 g of 60% sodium hydride in oil is added and the mixture is stirred at 4°C for 30 minutes. 0.451 g of 2,4-dimethoxybenzenesulphonyl chloride is then added and the mixture is stirred for 3 hours at RT. 50 ml of water are added to the reaction mixture, the resulting mixture is extracted with EtOAc, the organic phase is washed with 5% Na2C03 solution, with saturated NaCl solution and dried over Na2SO4, and the solvent is evaporated off under vacuum. The residue is chromatographed on alumina, eluting with a DCM/MeOH mixture (99.2/0.8; v/v). The two diastereoisomers are separated: - the less polar: compound of Example 7, 0.122 g of which is collected after crystallization from hexane; m.p. = 151°C af = -154° (c = 0.1; chloroform) - the more polar, compound of Example 8, which is obtained after crystallization from a DCM/iso- ether mixture; m.p. = 283°C ccj5 = +140° (c = 0.1; chloroform) Working according to the procedures described in the Examples above, starting with the compounds of formula (II) described in Preparations 3 and 2,4-dimethoxybenzenesulphonyl chloride, the compounds according to the invention collated in Table I below are prepared: Table I (a) This compound is prepared according to the procedure described in Example 3, starting with the compound obtained in Preparation 3,6, isomer B. The product is chromatographed on silica gel, eluting witl a DCM/MeOH mixture (97/3; v/v). (b) This compound is prepared according to the procedure described in Example 3, starting with the compound obtained in Preparation 3.8, isomer B. The product is chromatographed on silica gel, eluting with a DCM/MeOH mixture (96/4; v/v). (c) This compound is prepared according to the procedure described in Example 3, starting with the compound obtained in Preparation 3.10, isomer B. The product is chromatographed..on silica gel, eluting with ,a DCM/MeOH mixture (96/4; v/v). (d) This compound is prepared according to the procedure described in Example 3, starting with the compound obtained in Preparation 3.12, isomer B. The product is chromatographed on silica gel, eluting with a DCM/MeOH mixture (96/4; v/v). (e) This compound is prepared according to the procedure described in Example 1, starting with the compound obtained in Preparation 3.14, isomer B. The product is chromatographed on silica crel, eluting with a DCM/MeOH mixture (98.5/1.5; v/v). (f) This compound is prepared according to the procedure described in Example 1, starting with the compound obtained in Preparation 3.16, isomer B. The product is chromatographed on silica gel, eluting with a DCM/MeOH mixture (98.5/1.5; v/v). (g) This compound is prepared according to the procedure described in Example 1, starting with the compound obtained in Preparation 3.18, isomer B. The product is chromatographed on silica gel, eluting with a DCM/MeOH mixture (98/2; v/v). (h) This compound is prepared according to the procedure described in Example 1, starting with the compound obtained in Preparation 3.22, isomer B. The product is chromatographed on silica gel, eluting with a DCM/MeOH mixture (98.5/1.5; v/v). (i) This compound is prepared according to the procedure described in Example 3/ starting- with the compound obtained in Preparation 3.24, isomer B. The product is chromatographed on silica gel, eluting with a DCM/EtOAc mixture (80/20; v/v). (j) This compound is prepared according to the procedure described in Example 3, starting with the compound obtained in Preparation 3.26, isomer B. The product is chromatographed on silica gel, eluting with a DCM/MeOH mixture (91/9; v/v). *H NMR: DMSO-d6: (ppm) : 1.4 to 3.3: m: 10H; 3.4 to 3.95: 3s: 9H; 4.2 to 5.0: m: 3H; 6.6 to 8.0: m: 9H. (k) This compound is prepared according to the procedure described in Example 3, starting with the compound obtained in Preparation 3.28, isomer B. (1) This compound is prepared according to the procedure described in Example 3, starting with the compound obtained in Preparation 3.30, isomer B. The product is chromatographed on silica gel, eluting with a DCM/MeOH mixture (97/3; v/v) (m) This compound is prepared according to the procedure described in Example 3, starting with the compound obtained in Preparation 3.31 (mixture of diastereqisomers). The product is chromatographed on silica gel, eluting with a DCM/EtOAc mixture (50/50; v/v) and the (-) isomer is separated out. (n) This compound is prepared according to the procedure described in Example 3, starting with the compound obtained in Preparation 3.33. The product is chromatographed on silica gel, eluting with a DCM/MeOH mixture (95.5/4.5; v/v). (o) This compound is prepared according to the procedure described in Example 3, starting with the compound obtained in Preparation 3.35, isomer B. (p) This compound is prepared according to the procedure described in Example 3, starting with the compound obtained in Preparation 3.37, isomer B. The product is chromatographed on alumina, eluting with a DCM/EtOAc mixture (97/3; v/v). (q) This compound is prepared according to the procedure described in Example 3, starting with the compound obtained in Preparation 3.39, isomer B. The product is chromatographed on silica gel, eluting with DCM. (r) This compound is prepared according to the procedure described in Example 3, starting with the compound obtained in Preparation 3.40. The product is chromatographed on silica gel, eluting with DCM and then with a DCM/MeOH mixture (99/1; v/v). (s) This compound is prepared according to the procedure described in Example 3, starting with the compound obtained in Preparation 3.42. The product is chromatographed on silica gel, eluting with a DCM/MeOH mixture (96/4; v/v). EXAMPLE 28 tert-Butyl 2-[[(3R, 5S)-1-[5-chloro-1-[(2,4-dimethoxyphenyl)sulphonyl]-3-(2-methoxyphenyl)-2-OXO-2,3-dihydro-lH-indol-3-yl]-5-[(dimethylamino)-carbonyl]-3-pyrrolidinyl]oxy]acetate, laevorotatory isomer. (I) : R1 = C1; R2 = H; R3 = OCH3; R4 = H; R5 = N(CH3)2; Re = -CH2COOC(CH3)3; R7 = 2-OCH3; R8 = OCH3. This compound is prepared according to the procedure described in Example 3, starting with 2.9 g of the compound obtained in Preparation 3.44 (isomer B), 0.233 g of 60% sodium hydride in oil, 15 ml of DMF and 1.25 g of 2,4-dimethoxybenzenesulphonyl chloride. The product is chromatographed on silica gel, eluting with a DCM/EtOAc mixture (80/20; v/v). 3 g of the expected product are obtained after crystallization from hexane. = -159° (c = 0.23; chloroform). EXAMPLE 29 2-[[(3R, 5S)-l-[5-Chloro-l-[(2,4-dimethoxy-phenyl)sulphonyl]-3-(2-methoxyphenyl)-2-oxo-2,3-dihydro-lH-indol-3-yl]-5-[(dimethylamino)carbonyl]-3-pyrrolidinyl]oxy]acetic acid 0.55 trifluoroacetate, laevorotatory isomer. (I), TFA: R1 = C1; R2 = H; R3 = OCH3; R4 = H; R5 = N(CH3)2; Re = -CH2COOH; R7 = 2-OCH3; R8 = OCH3 - A mixture of 3 g of the compound obtained in Example 28 and 15 ml of TFA in 15 ml of DCM is stirred :or 3 hours at RT. The reaction mixture is concentrated mder vacuum, the residue is taken up in iso-ether and ;he precipitate formed is spin-filtered off. 2.2 g of :he expected product are obtained. = -179° (c = 0.31; chloroform). EXAMPLE 3 0 (2S, 4R)-l-[5-Chloro-l-[(2,4-dimethoxy-henyl)sulphonyl]-3-(2-methoxyphenyl)-2-oxo-,3-dihydro-lH-indol-3-yl]-4-[2-[[2-hydroxy-l-hydroxymethyl)-1-methylethyl]amino]-2-oxoethoxy]-N,N- dimethyl-2-pyrrolidinecarboxamide, laevorotatory isomer. (I) : R1 = C1; R2 = H; R3 = OCH3; R4 = H; R5 = N(CH3)2; R6 = -CH2CONHC (CH3) (CH2OH)2; R7 = 2-OCH3; R8 = OCH3. A mixture of 0.5 g of the compound obtained in Example 29, 0.085 g of 2-amino-2-methyl-1,3-propanediol, 0.290 g of BOP and 0.187 g of triethylamine in 2 0 ml of DCM is stirred for 3 hours at RT. The reaction mixture is diluted by addition of DCM, the organic phase is washed with water, with saturated Na2C03 solution and dried over Na2SO4, and the solvent is evaporated off under vacuum. The residue is chromatographed on silica gel, eluting with a DCM/MeOH mixture (94/6; v/v). 0.31 g of the expected product is obtained after crystallization from iso-ether; m.p. = 154°C. (XD° = -142°~(c = 0.19; chloroform")". EXAMPLE 31 (2S, 4R)-l-[5-Chloro-l-[(2,4-dimethoxy-phenyl)sulphonyl]-3-(2-methoxyphenyl)-2-oxo-2,3-dihydro-lH-indol-3-yl]-N,N-dimethyl-4-[2-oxo-2-(1-piperazinyl)ethoxy]-2-pyrrolidinecarboxamide bis(trifluoroacetate), laevorotatory isomer. (I), 2TFA: R1 = C1; R2 = H; R3 = 0CH3; R4 = H; R5 = -N(CH3)2; R6 = -CH2-CO - N NH ; R7 = 2-OCH. • R3 = OCH3 A) A mixture of 0.7 g of the compound obtained in Example 29, 0.2 g of 1-(tert-butoxycarbonyl)- piperazine, 0.404 g of BOP and 0.263 g of triethylamine in 20 ml of DCM is stirred for 2 hours at RT. Water is added to the reaction mixture and the resulting mixture is extracted with DCM, the organic phase is washed with saturated Na2C03 solution and dried over Na2S04/ and the solvent is evaporated off under vacuum. The residue is chromatographed on silica gel, eluting with a DCM/MeOH mixture (97/3; v/v). The product thus obtained is taken up in hexane and the precipitate formed is spin-filtered off to give 0.7 g. B) A mixture of 0.7 g of the compound obtained in step A and 10 ml of TFA in 10 ml of DCM is stirred for 3 hours. The reaction mixture is concentrated under vacuum, the residue is taken up in ether and the precipitate formed is spin-filtered off. 0.6 g of the expected product is obtained; m.p. = 166°C. = -133° (c = 0.27; chloroform). EXAMPLE 32 (2S, 4R)-l-((2,4-Dimethoxypheny1)sulphonyl) -3- (2-methoxyphenyl) -2-oxo-2, 3-dihydro-lif-indol-3-yl] -N,N-dimethyl-4-[2-oxo-2-(4-morpholinyl)ethoxy]- 2-pyrrolidinecarbQxamide, laevorotatory isomer. (I) : R1 = C1; R2 = H; R3 = OCH3; R4 = H; R5 = -N(CH3)2; R6 = -CHj-CO- N 0 ; R7 = 2-OCH3 ; R8 = OCH3. A mixture of 0.6 g of the compound obtained in Example 29, 0.085 g of morpholine, 0.347 g of BOP and 0.227 g of triethylamine in 20 ml of DCM is stirred for 2 hours at RT. The reaction mixture is extracted with DCM, the organic phase is washed with water and dried over Na2SCO4, and the solvent is evaporated off under vacuum. The residue is chromatographed on silica gel, eluting with a DCM/MeOH mixture (95/5; v/v). 0.53 g of the expected product is obtained after crystallization from iso-ether; m.p. = 210°C. a20 = -153° (c = 0.28; chloroform). EXAMPLES33.and 34 (3R, 5S)-l-[5-Chloro-l-[(2,4-dimethoxyphenyl)sulphonyl]-3-(2-methoxyphenyl)-2-oxo-2,3-dihydro-lH-indol-3-yl]-5-[(dimethylamino)carbonyl]-3-pyrrolidinyl 3-(4-morpholinyl)propanoate, laevorotatory isomer and dextrorotatory isomer. (I) : R1 = C1; R2 = H; R3 = OCH3; R4 = H; R5 = -N(CH3)2; These compounds are prepared according to the procedure described in Example 3, starting with 3.1 g of the compound obtained in Preparation 3.45, 20 ml of DMF, 0.238 g of 60% sodium hydride in oil and 1.27 g of 2,4-dimethoxybenzenesuiphonyl chloride. The product is chromatographed on silica gel, eluting with a DCM/MeOH mixture (90/10; v/v). The two diastereoisomers are separated: - the less polar: compound of Example 33, 2.8 g of which are obtained after solidification in hexane. = -154° (c = 0.3; chloroform). - the more polar: compound of Example 34, 1.3 g of which are obtained after solidification in hexane. = +127°- (c = 0 .2 9 ; chloroform)" We Claim: 1. Compound of formula (la) wherein: - R1 represents a chlorine atom, a methyl radical or a trifluoromethoxy radical; - R2 represents a hydrogen atom or is in position -6- of the indol-2-one and represents a chlorine atom, a methyl radical, a methoxy radical or a trifluoromethyl radical; - R3 represents a chlorine atom, a fluorine atom, a methoxy radical or an ethoxy radical; - R4 represents a hydrogen atom or is in position -3-or -4- of the phenyl and represents a fluorine atom or a methoxy radical; - or R4 is in position -3- of the phenyl and, together with R3, represent a methylenedioxy radical; - R5 represents a dimethylamino radical or a methoxy radical - R6 represents a hydrogen atom; a methyl radical; an ethyl radical; a tert-butyloxycarbonylmethyl radical; a carboxymethyl radical; a [[2-hydroxy -1- (hydroxymethyl) -1-methylethyl] amino] carbonylmethyl 1- (hydroxymethyl) -1-methylethyl] amino] carbonylmethyl radical; a (l-piperazinyl)carbonylmethyl radical; a (4-morpholinyl) carbonylmethyl radical; a 3- (4-morpholinyl)propanoyl radical; R7 is in position -2- of the phenyl and represents a methoxy radical; R8 represents a methoxy radical; and the salts thereof with mineral or organic acids, and the solvates and/or hydrates thereof. 2. Compound as claimed in claim 1, chosen from: (2S, 4R)-l-[5-Chloro-l-[ (2,4-dimethoxyphenyl)-sulphonyl] -3- (2- methoxy-phenyl) -2-oxo-2, 3-dihydro- lH-indol-3-yl] -4-hydroxy-N, N- dimethyl2-pyrrolidinecarboxamide, laevorotatory isomer; (2S, 4R)-l-[5-Chloro-l-[ (2,4-dimethoxyphenyl)- sulphonyl ]-3- (2- methoxyphenyl) -2-oxo-2, 3-dihydro- lH-indol-3-yl] -4-methoxy-N,N- dimethyl- 2 -pyrrolidinecarboxamide, laevorotatory isomer; (2S, 4R)-l-[5-Chloro-3-(2-chlorophenyl)-l- [(2, 4- dimethoxyphenyl) sulphonyl] -2-oxo- 2,3-dihydro-lH-indol-3-yl]-4-hydroxy- N,N-dimethyl- 2- pyrrolidinecarboxamide, laevorotatory isomer; (2S, 4R)-l-[5-Chloro-3~(2-chlorophenyl)- 1- [(2, 4-dimethoxyphenyl) sulphonyl]-6-methoxy-2-oxo- 2,3—dihydro-1H-indol-3-yl] -4-methoxy- N,N-dimethyl- 2-pyrrolidinecarboxamide, laevorotatory isomer; (2S, 4R)-l-[5-Methyl-l-[(2,4-dimethoxyphenyl)- sulphonyl] -3- (2 methoxyphenyl) -2-oxo-2, 3-dihydro- lH-indol-3-yl] -4-hydroxy-N,N dimethyl- 2 -pyrrolidinecarboxamide, laevorotatory isomer; (2S, 4R)-l-[5-Trifluoromethoxy-l-[(2, 4-dimethoxy- phenyl) sulphonyl] - 3- (2-methoxyphenyl) -2-oxo- 2,3-dihydro-lH-indol-3-yl] -4-hydroxy- N,N-dimethyl- 2- pyrrolidinecarboxamide, laevorotatory isomer; (2S, 4R)-l-[5-Chloro-l-[(2,4-dimethoxyphenyl)- sulphonyl]-3- (2- methoxyphenyl) -6—methyl-2-oxo- 2,3-dihydro-lH-indol-3-yl]-4- hydroxy-N,N-dimethyl- 2-pyrrolidinecarboxamide, laevorotatory isomer; (2S, 4R)-l-[3-(2-Chlorophenyl)-l-[(2,4-dimethoxy-phenyl) sulphonyl] -5, 6-dimethyl-2-oxo-2, 3-dihydro-lH-indol-3-yl] -4-hydroxy-N,N-dimethyl- 2-pyrrolidinecarboxamide, laevorotatory isomer; (2S, 4R)-l-[5-Chloro-l-[(2,4-dimethoxyphenyl)-sulphonyl] -3- (2, 3- dimethoxyphenyl) -2-oxo-2, 3-dihydro-lH-indol-3-yl] -4-methoxy-N,N- dimethyl- 2-pyrrolidinecarboxamide, laevorotatory isomer; (2S, 4 R) -1- [5 Chloro -l-[2,4 -dimenthoxyphenyl)- sulphonyl] -3- (2- methoxyphenyl)-6-trifluoromethyl-2- oxo-2, 3-dihydro-lH-indol-3- yl] - 4- methoxy-N, N-dimethyl-2-pyrrolidinecarboxamide, laevorotatory isomer; (2S, 4R)-l-[6-Chloro-l-[(2,4-dimethoxyphenyl)-sulphonyl] -3- (2-methoxyphenyl) -5-methyl-2-oxo-2, 3-dihydro-lH-indol-3-yl] -4-metboxy- N.N-dimethyl- 2-pyrrolidinecarboxamide, laevorotatory isomer; (2S, 4R)-l-[5-Chloro-l-[(2,4-dimethoxyphenyl)-sulphonyl] -3- (2- methoxyphenyl) -2-oxo-2, 3-dihydro-lH-indol-3-yl]-4-ethoxy-N,N- dimethyl-2-pyrrolidine-carboxamide, laevorotatory isomer; (2S, 4R)-l-[5-Chloro-l-[ (2,4-dimethoxyphenyl)-sulphonyl] -3- (2, 3- dimethoxyphenyl) -2-oxo-2, 3-dihydro-lH-indol-3-yl] -4-hydroxy-N,N- dimethyl- 2-pyrrolidinecarboxamide, laevorotatory isomer; (2S, 4R)-l-[5,6-Dichloro-3-(2-chlorophenyl)-l- [ (2,4-dimethoxyphenyl) sulphonyl]-2-oxo- 2, 3-dihydro-lH-indol-3-yl] -4-hydroxy-N,N- dimethyl- 2-pyrrolidinecarboxamide, laevorotatory isomer; Methyl (2S, 4R)-l-[5-chloro-l-[ (2,4-dimethoxyphenyl) sulphonyl]-3- (2-methoxyphenyl) -2-oxo-2, 3-dihydro-lH-indol-3-yl]-4-methoxy-2-pyrrolidinecarboxylate, laevorotatory isomer; Methyl (2S, 4R)-l-[5-chloro- 1- [(2, 4-dimethoxyphenyl)sulphonyl] -3-(2-methoxyphenyl) -6-methyl-2-oxo-2, 3-dihydro-lH-indol-3-yl] -4-methoxy-2-pyrrolidinecarboxylate, laevorotatory isomer; 2S, 4R)-l-[5-Chloro-l-[ (2,4-dimethoxyphenyl)-sulphonyl] -3- (2-ethoxyphenyl) -2-oxo-2, 3-dihydro-lH-indol-3-yl] -4-hydroxy-N,N-dimethyl-2-pyrrolidinecarboxamicide, laevorotatory isomer; 2S, 4R)-l-[5-Chloro-l-[(2,4-dimethoxyphenyl)-sulphonyl]-3- (2, 3-difluorophenyl) -2-oxo- 2,3-dihydro-lH-indol-3-yl]-4-hydroxy-N,N-dimethyl- 2-pyrrolidinecarboxamide, laevorotatory isomer; (2S, 4R)-l-[5-Chloro-l-[(2,4-dimethoxyphenyl-sulphonyl] -3- (2,4-dimethoxyphenyl) -2-oxo-2, 3-dihydro-lH-indol-3-yl]-4-hydroxy-N,N-dimethyl- 2-pyrrolidinecarboxamide, laevorotatory isomer; (2S, 4R)-l-[5-Chloro-l-[(2,4-dimethoxyphenyl)-sulphonyl] -3- (1, 3-benzodioxol-4-yl) -2-oxo-2,3-dihydro-lH-indol-3-yl] -4-hydroxy-N,N-dimethyl- 2-pyrrolidinecarboxamide, laevorotatory isomer; (2S, 4R)-1—[5,6-Dichloro-l-[(2,4-dimethoxyphenyl)sulphonyl]-3-(2-methoxyphenyl) -2-oxo-2,3-dihydro-lH-indol-3-yl]-4-hydroxy-N, N- dimethyl-2-pyrrohidinecarboxamide, laevorotatory isomer; tert-Butyl 2-[[(3R, 5S)-l-[5-chloro-l-[(2,4—dimethoxyphenyl) sulphonyl] -3- (2-methoxyphenyl) -2-oxo-2, 3-dihydro-1H-indol-3-yl] -5- [ (dime thy lamino)carbonyl 1 -3-pyrrolidinyl]oxylacetate, laevorotatory isomer; 2-[[(3R, 5S)-1—[5-Chloro-l-(2,4— dimethoxyphenyl) sulphonyl] -3- (2- methoxyphenyl) -2-oxo-2, 3-dihydro-lH-indol-3-yl] -5- [(dimethylamino)carbonyl -3-pyrrolidinyl]oxy] acetic acid, laevorotatory isomer; (2S, 4R)-l-[5-Chloro-l-[(2,4-dimethoxyphenyl)-sulphonyl]-3- (2- methoxyphenyl) -2-oxo-2,3-dihydro-lH-indol-3-yl] -4- [2-[ [2-hydroxy-l- (hydroxymethyl) -1-methylethyl] amino] -2-oxoethoxy] -N,N-dlmethyl- 2-pyrrolidinecarboxamide, laevorotatory isomer; (2S, 4R)-l-[5-Chloro-l-[ (2,4-dimethoxyphenyl)-sulphonyl] -3- (2- methoxyphenyl) -2-oxo-2, 3-dihydro- lH-indol-3-yl] -N,N-dimethyl -4- [2-oxo- 2- (1-piperazinyl) ethoxy] -2-pyrrolidinecarboxamide, laevorotatory isomer; (2S, 4R)-1- [ [ (2,4-Dimethoxyphenyl)sulphonyl]- 3- (2- methoxyphenyl)-2-oxo-2,3-dihydro-lH-indol-3-yl] -N,N-dimethyl-4- [2- oxo-2- (4-morpholinyl) ethoxy] -2-pyrrolidinecarboxamide, laevorotatory isomer; (3R, 5S)-l-[5-Chloro-l-[(2,4-dimethoxyphenyl)- sulphonyl] -3- (2- methoxy-phenyl) -2-oxo-2, 3-dihydro-lH-indol-3-yl] -5-[ (dimethylamino) carbonyl] - 3-pyrrolidinyl 3- (4-morphcolinyl) propanoate, laevorotatory isomer; as well as the possible salts thereof with mineral or organic acids, and the solvates and/or hydrates thereof. 3. Compound as claimed in claim 2 which is : -(2S, 4R)-l-[5-Chloro-l-[(2,4-dimethoxyphenyl) -sulphonyl] -3- (2-methoxyphenyl) -2-oxo-2, 3-dihydro-lH-indol-3-yl] -4-hydroxy-N,N-dimethyl-2- pyrrolidinecarboxamide, laevorotatory isomer. 4. Process for preparing compounds of formula (la) laevorotatory isomer as claimed in claim 1, possible salts thereof with mineral or organic acids and solvates and/or hydrates thereof, characterized in that: wherein the carbon atom bearing substituent OR6 has the (R) configuration, Ri, R2, R3, R4, R5 and R are as defined for a compound of formula (la) laevorotatory isomer in Claim 1, is reacted, in the presence of a base, with a halide of formula: (III) in which R7 and R8 are as defined for a compound of formula (la) laevorotatory isomer in Claim 1 and Hal represents a halogen atom. Dated this 2002. 2nd day of July, (RANJNAJWEHTA-DUTT) OF REMFRY 8B SAGAR ATTORNEY FOR THE APPLICANTS