METHOD OF OBTAINING 3-ETHYL-5-METHYL(+)2-2-(N-TRITHYLAMINE)ETHOXYETHYL-4-2-CHLOROPHENYL)-1,4-DIHYDRO-6-METHYLPYRIDINODICARBOXYLATE-3,5 AND 3-ETHYL-5-METHYL(+)2-2-(N-TRITHYLAMINE)ETHOXYETHYL-4-2-CHLOROPHENYL)-1,4-DIHYDRO-6-METHYLPYRIDINODICARBOXYLATE-3,5 OBTAINED THEREBY

摘要

There is disclosed a process for the preparation of 3-ethyl 5-methyl (+/-) 2-[(2-aminoethoxy)methyl]-4-(2-chlorophenyl)-1,4- dihydro-6-methyl-3,5-pyridine-dicarboxylate monobenzenesulphonate (amlodipine benzenesulphonate) of formula CHEM wherein 3-ethyl 5-methyl (+/-) 2-[2-(N-tritylamino)-ethoxymethyl]-4-(2-chlorophenyl)-1,4-dihydro-6-me thyl-3,5- pyridinedicarboxylate is reacted with benzenesulphonic acid in a methanolic or an aqueous methanolic medium at a temperature from 20 DEG C to the reflux temperature and the title compound is isolated and purified. Amlodipine benzene sulphonate is a valuable anti-ischaemic and anti-hypertensive agent.