2-l-Rhamnopyranosyl[1,2,4]triazolo[1,5-a]pyridine. 4' and 3' Oxidation products. Synthesis and structure-activity relationships.

A series of 2-alpha-L-rhamnopyranosylnitro[1,2,4]triazolo[1,5-a] pyridine C-nucleosides was synthesized from the condensation oa thioiminoether with nitro-2-pyridylhydrazines. Catalytic reduction afforded the corresponding amino derivative. A 1',2' unsaturated C-nucleoside was also obtained by two different routes. Selective oxidation gave the 3'- and 4'-ketonucleosides. The cytotoxic properties of the nucleosides, as well as their effect on viral transformation and replication, were described. The nitro derivatives inhibit viral replication, but at toxic doses; the introduction of a keto function leads to a product which inhibits the replication of murine leukemia virus (MuLV) at noncytotoxic concentrations. The amino derivatives have no significant antiviral effect.