SELECTIVE SYNTHESIS OF POLYAMINE DERIVATIVES - EFFICIENT DERIVATIZATION OF THE SECONDARY AMINO GROUP OF N-MONOSUBSTITUTED 1,3-DIAMINES

N-Monosubstitute 1,3-diamines were selectively functionalized at the s econdary N-atom via 2-Ph-substituted hexahydropyrimidine intermediates . Reaction of the diamines with benzaldehyde, followed by treatment wi th an electrophile and hydrolysis, provided the desired products with excellent selectivity and in high yields. N-4,N-9-bis[3-phenylprop-2-e noyl]spermine (4a), which was further converted to N-1,N-12-bis[3-phen ylprop-2-enoyl]spermine (15) by a transamidation reaction, was prepare d by this way in 82% yield from spermine (1). Compound 4a was alternat ively synthesized in 83% yield, equally from 1, by a sequence involvin g intermediary protection of the terminal amino groups.