Abstract: Chiral 1-(4-methylphenylmethyl)-5-oxo-{N-[(3-t-butoxycarbonyl-aminomethyl)]-piperidin-1-yl}-pyrrolidine-2-carboxamides as inhibitors of collagen induced platelet activation and adhesion. The present invention provides chiral (2S)-1-(4-methylphenylmethyl)-5-oxo-(3S)-{N-[(3-t-butoxycarbonyl aminomethyl)]-piperidin-1-yl}-pyrrolidine-2-carboxamide, and (2S)-1-(4-methylphenylmethyl)-5-oxo-(3R)-{N-[(3-t-butoxycarbonyl amino methyl)]-piperidin-1-yl}-pyrrolidine-2-carboxamide of formula 6 and 7 respectively. The present invention also relates to use of these moieties as inhibitors of collagen induced platelet adhesion and aggregation mediated through collagen receptors. The present invention provides a process for preparation of chiral carboxamides of formula 6 and 7 using the process which has advantage to avoid any racemization at the a-carboxylic center, during N-alkylation. The reagent LiHMDS is used at low temperatures to furnish methyl N-(p-methylphenylmethyl)1pyroglutamate in good chiral purity.

Abstract: Chiral 1-(4-methylphenylmethyl)-5-oxo-{N-[(3-t-butoxycarbonyl-aminomethyl)]-piperidin-1-yl}-pyrrolidine-2-carboxamides as inhibitors of collagen induced platelet activation and adhesion. The present invention provides chiral (2S)-1-(4-methyl-phenylmethyl)-5-oxo-(3S)-{N-[(3-t-butoxycarbonyl aminomethyl)]-piperidin-1-yl}-pyrrolidine-2-carboxamide, and (2S)-1-(4-methylphenylmethyl)-5-oxo-(3R)-{N-[(3-t-butoxycarbonyl amino methyl)]-piperidin-1-yl}-pyrrolidine-2-carboxamide of formula 6 and 7 respectively. The present invention also relates to use of these moieties as inhibitors of collagen induced platelet adhesion and aggregation mediated through collagen receptors. The present invention provides a process for preparation of chiral carboxamides of formula 6 and 7 using the process which has advantage to avoid any racemization at the a-carboxylic center, during N-alkylation. The reagent LiHMDS is used at low temperatures to furnish methyl N-(p-methylphenylmethyl)1pyroglutamate in good chiral purity.

Abstract: Chiral 1-(4-methylphenylmethyl)-5-oxo-{N-[(3-t-butoxycarbonyl-aminomethyl)]-piperidin-1-yl}-pyrrolidine-2-carboxamides as inhibitors of collagen induced platelet activation and adhesion The present invention provides chiral (2S)-1-(4-methyl-phenylmethyl)-5-oxo-(3S)—{N-[(3-t-butoxycarbonyl aminomethyl)]-piperidin-1-yl}-pyrrolidine-2-carboxamide, and (2S)-1-(4-methylphenylmethyl)-5-oxo-(3R)—{N-[(3-t-butoxycarbonyl amino methyl)]-piperidin-1-yl}-pyrrolidine-2-carboxamide of formula 6 and 7 respectively. The present invention also relates to use of these moieties as inhibitors of collagen induced platelet adhesion and aggregation mediated through collagen receptors. The present invention provides a process for preparation of chiral carboxamides of formula 6 and 7 using the process which has advantage to avoid any racemization at the a-carboxylic center, during N-alkylation. The reagent LiHMDS is used at low temperatures to furnish methyl N-(p methylphenylmethyl)lpyroglutamate in good chiral purity.