4-Piperidinol, 1-butyl-4-phenyl-, phenylacetate, hydrochloride 63916-33-6 Acetic acid, phenyl-, 4-(1-butyl-4-phenyl)piperidyl ester, hydrochloride NU-1820 Piperidine, 1-butyl-4-phenyl-4-phenylacetoxy-, hydrochloride