Direct selective acylation of the primary amino functions of spen-nine and spermidine with a variety of isolable succinimidyl cinnamates. followed by catalytic hydrogenation, gave high yields of the spermine alkaloid kukoamine A and analogs suitable for structure-activity relationship studies. Suitable succinimidyl cinnamates were readily obtained through Wittig reaction of aromatic aldehydes with the ylides Ph3P=CRCO2Me, followed by saponification and activation with N-hydroxysuccinimide in the presence of N,N'-dicyclohexylcarbodiimide.