6-Thiopurine riboside analogs: their toxicity and metabolism in Leishmania donovani and mammalian cells.

Abstract

The purine nucleoside analog, allopurinol riboside, is cytotoxic to several Leishmania sp1. This nucleoside was metabolized to its 5′-monophosphate by L. donovani which, in turn, was aminated to form adenine nucleotide analogs. The aminopyrazolopyrimidine 5′-triphosphate thus formed was incorporated into the RNA of the parasite. Several purine nucleoside analogs, structurally similar to allopurinol riboside. have differential cytotoxicity to Leishmania donovani and mouse L cells2. The cytotoxic action of these compounds correlates with their conversion to ATP and/or GTP analogs by these organisms3.