tert-butyl [(tert-butoxycarbonyl)amino](4-{[2-(2-naphthylsulfonyl)-1-(1-piperidinylcarbonyl)hydrazino]methyl}-1-piperidinyl)methylidenecarbamate

tert-butyl (4-{[1-(1-azepanylcarbonyl)-2-(2-naphthylsulfonyl)hydrazino]methyl}-1-piperidinyl)[(tert-butoxycarbonyl)amino]methylidenecarbamate

tert-butyl [(tert-butoxycarbonyl)amino](4-{[1-(4-morpholinylcarbonyl)-2-(2-naphthylsulfonyl)hydrazino]methyl}-1-piperidinyl)methylidenecarbamate

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

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