| abstract |
A compound of formula (I):wherein R1 is hydrogen or a substituent group; R2 is amino or a substituent group; N* is amino when R1 is hydrogen or =NH when R1 is a substituent group; R3 and R4 are both carbocyclic, heterocyclic or alkyl groups and may be same or different; and R5 is hydrogen, alkyl or a cyclic aryl group, with the proviso that: when R3 and R4 are both alkyl they are linked to form a cycloalkyl group, and R5 is a cyclic aromatic group; and when R3 and R4 are both carbocyclic or heterocyclic groups, R5 is hydrogen or an alkyl group; or a salt thereof. Preferably, R2 is NH2and R3 and R4 together form a cycloalkyl group such as cyclopropyl, cyclopentyl or cyclohexyl and R5 is optionally substituted phenyl; or R2 is NH2and R3 and R4 are both optionally substituted phenyl or optionally substituted thienyl and R5 is hydrogen. The compounds are useful as sodium channel blockers and as antimalarials. |