(3-alpha,4-beta,6-beta)-1,3-Dimethyl-4-ethynyl-6-(4-methylphenyl)-3,4-piperidinediol 120729-76-2 3,4-Piperidinediol, 1,3-dimethyl-4-ethynyl-6-(4-methylphenyl)-, (3-alpha,4-beta,6-beta)- cis-1,3-Dimethyl-4-ethynyl-6-(4-methylphenyl)-3,4-piperidinediol