Abstract: The present invention relates to a process for preparation of isotretinoin and more specifically, to a purification process for obtaining highly pure isotretinoin that is useful as a keratolytic agent, particularly useful for the treatment of acne.

Abstract: A one-pot industrial process for preparing 1,2,3,9-tetrahydro-9-methyl-3-[(2-methyl-1H-imidazole-1-yl)methyl]-4H-carbazol-4-one of Formula-(I) from 1,2,3,9-tetrahydro-9-methyl-4H-carbazol-4-one of Formula-(IV) involves reaction of Formula (IV) with HNR1R2 salt and paraformaldehyde, where R1,R2 are independently alkyl groups or together forms a cyclic alkyl group, in a solvent system of acetic acid and hydrocarbon solvent to form a crude mixture of intermediate compounds of Formula (III) and (VIII), which is converted to ondansetron (Formula (I)) without isolation by reaction with 2methyimidazole in a suitable solvent system in the same pot.

Abstract: Disclosed herein is an industrial preparation of Quetiapine by the reaction of 11-piperazinyldibenzo[b,f][1,4]-thiazepine or its salt with 2-(2-chloroethoxy)ethanol in presence of an organic or inorganic base under neat or aqueous condition to form 11-[4-{2-(2-hydroxyethoxy)ethyl}-1-piperazinyl]dibenzo[b,f]-[1,4]thiazepine. The quetiapine free base obtained is further converted to its hemi-fumarate salt.

Abstract: The present invention discloses selective and complete reduction of pyridine ring in a biaryl system comprising ?-substituted or nonsubstituted benzene ring and relates more specifically, not exclusively, for the manufacture of methylphenidate, which is used for treatment of Attention Deficit Hyperactive Disorder (ADHD) and also acts as central nervous system stimulant, by using palladium/C in a solvent such as C1-C4 alcohols in presence of molar quantities of organic and/or inorganic acids.

Abstract: N-7 isomer of the formula ##STR1## is converted into a N-9 isomer of the formula ##STR2## by heating a suspension of the N-7 isomer in an alkylating agent of the formula ##STR3##

Abstract: This invention relates to an improved regiospecific process for the synthesis of acyclic nucleosides such as, acyclovir and ganciclovir, anti-viral compounds especially effective against herpes virus, and intermediates thereof starting from dyacylguanine and an alkylating agent, selected from 2-oxa-1,4-butanediol diacetate (OBDDA), 1,4-diacetoxy-3-acetoxymethyl-2-oxa-butane, 1,4-dibenzyloxy-3-acetoxymethyl-2-oxabutane. The reaction is carried out in the absence of an acid catalyst and a solvent.