ethyl (2R,4R)-1-[(2S)-2-[[(1,1-dimethylethoxy)carbonyl]amino]-5-[[imino(nitroamino)methyl]amino]-1-oxopentyl]-4-methylpiperidine-2-carboxylate
ethyl trans-(±)-4-methylpiperidine-2-carboxylate
ethyl (2R,4R)-4-methyl-2-piperidinecarboxylate L-(+)-tartarate
ethyl (2S,4S)-4-methyl-2-piperidinecarboxylate L-tartrate
ethyl (2R-trans)-4-methylpiperidine-2-carboxylate