Synthesis of Solution-Phase Combinatorial Library of 4,6-Diamino-1,2-dihydro-1,3,5-triazine and Identification of New Leads Against A16V+S108T Mutant Dihydrofolate Reductase of Plasmodium falciparum Original Research Article

An efficient method to synthesize solution-phase combinatorial library of 1-aryl-4,6-diamino-1,2-dihydro-1,3,5-triazine was developed. The strategy involved an acid-catalyzed cyclocondensation between arylbiguanide hydrochlorides and carbonyl compounds in the presence of triethyl orthoacetate as water scavenger. A 96-membered combinatorial library was constructed from 6 aryl biguanides and 16 carbonyl compounds. Screening of the library by iterative deconvolution method revealed two candidate leads which are equally active against wild-type Plasmodium falciparum dihydrofolate reductase, but are about 100-fold more effective against the A16V+S108T mutant enzyme as compared to cycloguanil.