(E)-1,4-Diaminobut-2-ene dihydrochloride 1 (unsaturated putrescine) an
d some N-substituted derivatives of 1 have strong antifungal activity
against a variety of plant pathogens. A series of N-alkylated putresci
ne derivatives was synthesised and evaluated for antimalarial activity
in vitro against the asexual, intra-erythrocytic stages of Plasmodium
falciparum. (E)-N,N,N',N'-Tetraethyl-1,4-diaminobut-2-ene dihydrochlo
ride 3 was the most active N-alkylated putrescine tested. Enhanced in-
vitro activity was evident with the N,N'-bisbenzyl derivatives 7 and 1
1. Useful activity in vivo was observed only when the 7-chloroisoquino
lyl moiety was present, as in 12 (an unsaturated analogue of chloroqui
ne).