Abstract: A process for the preparation of (S)-Clopidogrel free base or a pharmaceutically acceptable salt thereof by the racemization of the undesired (R)-Clopidogrel in the presence of a suitable base followed by resolution with camphor sulfonate salt and further treatment with an inorganic acid to yield the title compound.

Abstract: The present invention relates to novel acid addition salts of sertraline, their preparation and their use in the preparation of crystalline Form-II of Sertraline hydrochloride.

Abstract: The present invention discloses a process for the synthesis and isolation of (2S, 3aS, 7aS)-1-[(2S)-2-[[(1S)-1-(ethoxycarbonyl)butyl]amino]-1-oxopropyl] octahydro-1H-indole-2-carboxylic acid and its tert-butylamine salt, by condensing (2S, 3aS, 7aS)-octahydroindole-2-carboxylic acid benzyl ester and N[(S)1-carboxybutyl]-(S)-alanine ethyl ester in nonreactive solvents in turn avoiding the formation of impurity viz. N-acetyl (2S,3aS,7aS)-octahydroindole-2-carboxylic acid benzyl ester (Formula V). The de-protection of benzyl ester group is optimized and then isolation of the product from aqueous layer by extraction using an organic solvent, which eliminates the need of lyophilization. The process of the present invention yields perindopril erbumnine salt of Formula 1B free of contaminants derivable from dicyclohexylcarbodiimide and impurities originated by the use of ethyl acetate.