Cinchonidine salt of (4S,5S)-5-(4-chlorophenyl)-1-(2,4-dichlorophenyl)-4-methyl-4,5-dihydro-1H-pyrazole-3-carboxylic acid, useful as intermediate in the preparation of cannabinoid CB1 neutral antagonists

摘要

The present invention relates to a cinchonidine salt of (4S,5S)-5-(4-chlorophenyl)-1-(2,4-dichlorophenyl)-4-methyl-4,5-dihydro-1H-pyrazole-3-carboxylic acid. This cinchonidine salt is prepared by enantiomeric resolution of a compound of formula (I) comprising:
the reaction of compound of formula (I) with cinchonidine in a suitable solvent, thereby resulting in the cinchonidine salt of the enantiomer (4S,5S) of formula (II); and optionally isolating said salt. The cinchonidine salt according to formula (II) is a useful intermediate in the preparation of a cannabinoid CB 1 neutral antagonist.