Abstract: The invention relates to improved method of synthesis for Treprostinil comprising condensation reaction of the carbonyl compound having allyl, alkyl, crotyl or MEM-protected phenolic hydroxyl group, compound (4) with a hydroxyl-protected alkynol (5) to give the condensation product, compound (6). Subjecting compound (6) to oxidation, reduction, hydroxyl protection and carbonylation, cyclization reactions gave the tricyclic derivative (10). Further reactions comprising reduction, hydrogenation and deprotection of the phenolic and side-chain hydroxyl groups, wherein the sequence and choice of reagents was governed by protecting groups, gave the triol intermediate, compound (14). Cyanoalkylation at phenolic hydroxyl functionality and further hydrolysis yielded the prostacyclin compound, Treprostinil (1) and its pharmaceutically acceptable salts, having desired purity.

Abstract: The invention relates to an improved method for a 5+3+2 solution phase syntheses of Icatibant acetate (1) comprising coupling of suitably protected peptide fragments which on deprotection followed by treatment with acetic acid provide Icatibant acetate (1) having desired purity.

Abstract: The invention relates to improved method of synthesis for Treprostinil comprising condensation reaction of the carbonyl compound having allyl, alkyl, crotyl or MEM-protected phenolic hydroxyl group, compound (4) with a hydroxyl-protected alkynol (5) to give the condensation product, compound (6). Subjecting compound (6) to oxidation, reduction, hydroxyl protection and carbonylation, cyclization reactions gave the tricyclic derivative (10). Further reactions comprising reduction, hydrogenation and deprotection of the phenolic and side-chain hydroxyl groups, wherein the sequence and choice of reagents was governed by protecting groups, gave the triol intermediate, compound (14). Cyanoalkylation at phenolic hydroxyl functionality and further hydrolysis yielded the prostacyclin compound, Treprostinil (1) and its pharmaceutically acceptable salts, having desired purity.

Abstract: The present invention relates to the preparation of stable pyridone disulphide derivatives having general formula (I) and its stereoisomers, which are useful in the treatment of gastrointestinal disorders. Pyridone disulphide derivatives (I) wherein, R1, R2 and R3 are independently alkyl, alkoxy, halogen, halogenated alkoxy, halogenated alkyl, hydrogen and could be the same or different and X is CH or N. R1 is methyl, methoxy, fluorine, trifluoromethyl, difluoromethoxy and hydrogen, R2 is methyl, methoxy and hydrogen, and R3 is methyl and hydrogen.

Abstract: The present invention relates to the preparation of stable pyridone disulphide derivatives having general formula (I) and its stereoisomers, which are useful in the treatment of gastrointestinal disorders. Pyridone disulphide derivatives (I) wherein, R1, R2 and R3 are independently alkyl, alkoxy, halogen, halogenated alkoxy, halogenated alkyl, hydrogen and could be the same or different and X is CH or N. R1 is methyl, methoxy, fluorine, trifluoromethyl, difluoromethoxy and hydrogen, R2 is methyl, methoxy and hydrogen, and R3 is methyl and hydrogen.

Abstract: The present invention relates to the preparation of stable pyridone disulphide derivatives having general formula (I) and its stereoisomers, which are useful in the treatment of gastrointestinal disorders. Pyridone disulphide derivatives (I) wherein, R1, R2 and R3 are independently alkyl, alkoxy, halogen, halogenated alkoxy, halogenated alkyl, hydrogen and could be the same or different and X is CH or N. R1 is methyl, methoxy, fluorine, trifluoromethyl, difluoromethoxy and hydrogen, R2 is methyl, methoxy and hydrogen, and R3 is methyl and hydrogen.

Abstract: The present invention relates to the preparation of stable pyridone disulphide derivatives having general formula (I) and its stereoisomers, which are useful in the treatment of gastrointestinal disorders. Pyridone disulphide derivatives (I) wherein, R1, R2 and R3 are independently alkyl, alkoxy, halogen, halogenated alkoxy, halogenated alkyl, hydrogen and could be the same or different and X is CH or N. R1 is methyl, methoxy, fluorine, trifluoromethyl, difluoromethoxy and hydrogen, R2 is methyl, methoxy and hydrogen, and R3 is methyl and hydrogen.

Abstract: The present invention provides a simple and efficient method for synthesis of 4-[bis(2-chloroethyl)-amino]-L-phenylalanine hydrochloride. The process involves the treatment of 4-[bis(2-chloroethyl)-amino]-L-phenylalanine free base with hydrochloric acid in water followed by isolation of 4-[bis(2-chloroethyl)-amino]-L-phenylalanine hydrochloride of desired purity.

Abstract: The present invention provides a simple method for preparation of benzphetamine and its acid addition salt comprising reaction of methamphetamine hydrochloride of formula (III) with benzyl chloride and treating the isolated benzphetamine of formula (II) with an acid dissolved in an organic solvent to provide benzphetamine acid addition salt, more specifically, benzphetamine hydrochloride of formula (I).

Abstract: The present invention provides a simple and efficient method for synthesis of 4-[bis (2-chloroethyl)-amino]-L-phenylalanine hydrochloride. The process involves the treatment of 4-[bis(2-chloroethyl)-amino]-L-phenylalanine free base with hydrochloric acid in water followed by isolation of 4-[bis(2-chloroethyl)-amino]-phenylalanine hydrochloride of desired purity.