methyl 4-[(1-oxopropyl)phenylamino]-4-piperidinecarboxylate, methyl 4-<N-(1-oxopropyl)-N-phenylamino>-4-piperidinecarboxylate, 4-(methoxycarbonyl)-4-<(1-oxopropyl)phenylamino>piperidine, PIP033, METHYL 4-[(PROPIONYL)PHENYLAMINO]PIPERIDINE-4-CARBOXYLATE, 4-(N-propionyl-anilino)-piperidine-4-carboxylic acid methyl ester, EINECS 277-193-5, Norcarfentanil