(3-alpha,4-beta,6-beta)-1,3-Dimethyl-4-ethynyl-6-phenyl-3,4-piperidinediol 3,4-Piperidinediol, 1,3-dimethyl-4-ethynyl-6-phenyl-, (3-alpha,4-beta,6-beta)- 84687-60-5 cis-1,3-Dimethyl-4-ethynyl-6-phenyl-3,4-piperidinediol