Patent ID: 8404840
Filing Date: 2013-03-26
Classification: A61P,C07D

Abstract:
1. A process for the preparation of a compound having the following structural formula: wherein R is methyl or methoxy; the process comprising: a) reacting benzophenone with compound of Formula-3, wherein R′ is a straight or branched or cyclic C1-C6 alkyl group, in the presence of a base and in a solvent to provide compound of Formula-4, wherein R′ is as defined above, which on in-situ treatment with methanol in presence of a suitable acid provides compound of Formula-5 wherein R′ is as defined above; b) hydrolyzing the compound of Formula-5 in presence of a base in a solvent, followed by crystallization from hydrocarbon solvent provides compound of Formula-6 c) resolving the compound of Formula-6 by treating it with a resolving agent in a solvent, followed by crystallization from hydrocarbon solvent provides compound of Formula-7 d) reacting the compound of Formula-7 with an amine of formula NR in an ether solvent, ester solvent, polar aprotic solvent, ketone solvent, alcoholic solvent, hydrocarbon solvent, chloro solvent, water, or a mixture thereof, to provide compound of Formula-11 and isolating the compound of Formula-11; e) reacting the isolated compound of Formula-11 with an inorganic or organic acid in an ether solvent, ester solvent, polar aprotic solvent, ketone solvent, alcoholic solvent, hydrocarbon solvent, chloro solvent, water, or a mixture thereof to provide the compound of Formula-7; f) treating the compound of Formula-7 from step e) with alcohol of formula R′—OH, wherein R′ is defined as above, in presence of an acid catalyst followed by isolation from a hydrocarbon solvent, to provide compound of Formula-8 g) crystallizing the compound of Formula-8 using a solvent to provide crystalline compound of Formula-8, h) reacting the crystalline compound of Formula-8 with compound of Formula-9 wherein R is defined as above, in presence of a base in a solvent, to provide compound of Formula-10 wherein R and R′ are defined as above; i) hydrolyzing the compound of Formula-10 with a base in a solvent followed by isolation from an ester solvent, to provide the compound of Formula-1; j) reacting the compound of Formula-1 with an amine of formula NR in an ether solvent, ester solvent, polar aprotic solvent, ketone solvent, alcoholic solvent, hydrocarbon solvent, chloro solvent, water, or a mixture thereof, to provide compound of Formula-13 wherein R, R k) reacting the isolated compound of Formula-13 with an inorganic or organic acid in an ether solvent, ester solvent, polar aprotic solvent, ketone solvent, alcoholic solvent, hydrocarbon solvent, chloro solvent, water, or a mixture thereof to provide the compound of Formula-1; and l) purifying the compound of Formula-1 in a solvent to provide the compound of Formula-1 having purity greater than 99.00% by HPLC.