methyl 4-({1-[(cyclopentylamino)carbonyl]hydrazino}methyl)-1-piperidinecarboxylate

N-cyclopentyl-2-(2-naphthylsulfonyl)-1-(4-piperidinylmethyl)-1-hydrazinecarboxamide

N,N'-bis-Boc-S-methyl-isothiourea

methyl 4-({2-(tert-butoxycarbonyl)-1-[(cyclopentylamino)carbonyl]hydrazino}methyl)-1-piperidinecarboxylate

methyl 4-{[1-[(cyclopentylamino)carbonyl]-2-(2-naphthylsulfonyl)hydrazino]methyl}-1-piperidinecarboxylate