保护的4-苯基哌啶-4-羧酸

4-氰基-4-苯基哌嗪

1-苄基-4-苯基哌啶-4-羧酸

4-phenyl-1-phenylmethoxycarbonylpiperidine-4-carboxylic acid

benzyl 4-benzoylpiperidine-1-carboxylate