申请人:——
公开号:US20040176606A1
公开(公告)日:2004-09-09
3-ethyl 5-methyl (+/−) 2-[(2-aminoethoxy)methyl]-4-(2-chlorophenyl)-1,4-dihydro-6-methyl-3,5-pyridinedicarboxylate benzenesulfonate, containing overall impurities of significantly less than 0.3% is disclosed, as well as process for its preparation, according to which substance of 3-ethyl 5-methyl (+/−) 2-[2-(N-trialkylamino)ethoxymethyl]-4-(2-chlorophenyl)-1,4-dihydro-6-methyl-3,5-pyridinedicarboxylate is converted with benzenesulfonic acid in ethanol solution, at a temperature between 20° C. and reflux temperature, followed by isolation and purification of 3-ethyl 5-methyl (+/−) 2-[(2-aminoethoxy)methyl]-4-(2-chlorophenyl)-1,4-dihydro-6-methyl-3,5-pyridinedicarboxylate benzenesulfonate. Amlodipine benzenesulfonate is useful as an antiishemic and antihypertensive agent.