Racemic and optically active 1,3,3-trimethyl-4-phenyl-4-(propionyloxy)piperidine

The preparation and resolution of 1,3,3-trimethyl-4-phenyl-4-(propionyloxy)piperidine (5,3-methylprodine) are described, and the results of the antinociceptive activities of the products by hot-plate (mice) and tail-withdrawal (rats) tests are shown to support proposals made from a recent analysis of the stereochemical structure-activity relationships of C-methyl derivatives of the reversed ester of meperidine. Data of absolute configuration were obtained by X-ray crystallography of a hydrobromide salt.