N,N'-bis(tert-butoxycarbonyl)-N'-(4-chlorobenzyl)-N''-(1-pent-4-enyl)guanidine

6-(2,3-di-tert-butoxycarbonyl)guanidino-1-hexanal

4-[N',N''-bis(tert-butyloxycarbonyl)guanidino]phenyl N-(benzyloxycarbonyl)aminoisobutyrate