In vitro and in vivo antimalarial activities of a carbohydrate antibiotic, prumycin, against drug-resistant strains of Plasmodia.

Sir: In the course of our program to discover antimalarial antibiotics active against drug-resistant parasites, by screening soil microorganisms and antibiotic library of the Kitasato Institute for Life Sciences, we previously reported on various microbial metabolites exhibiting potent antimalarial properties1-4). Now, we find that prumycin5-7), a compound in the antibiotic library of our institute, has potent and moderately selective antimalarial activity in vitro and in vivo. We report here the antimalarial profiles of prumycin and its derivatives (Fig. 1) in comparison with those of clinically used antimalarial drugs, and also present some conclusions on structure-activity relationships. Prumycin was purified from the cultured broth of Streptomyces sp. strain No. F-10285,6). The derivatives (2-4) were synthesized according to our previous report7). Benzyl 4-amino-2-(benzyloxycarbonyl) amino-2,4-