Antiparasitic structure-activity relationships of congocidine derivatives.

Several congocidine analogs were synthesized and tested for in vivo activity against Trypanosoma congolense and in vitro activity against amastigotes of Leishmania tropica. The tripyrrole derivative, beta-([N-methyl-4-[N-methyl-4-(guanidinoacetamido)pyrrole-2-carboxamido]pyrrole -2-carboxamido]pyrrole-2-carboxamido)butyroamidine dihydrochloride, was less toxic and more active than congocidine. The guanidinoacetyl moiety appears to be a structural requirement for antiparasitic activity in the congocidine series.