Novel pyridinium-type fullerene derivatives as multitargeting inhibitors of HIV-1 reverse transcriptase, HIV-1 protease, and HCV NS5B polymerase.

Abstract In the present study, we newly synthesized four types of novel fullerene derivatives: pyridinium/ethyl ester-type derivatives 3b−3l, pyridinium/carboxylic acid-type derivatives 4a, 4e, 4f, pyridinium/amide-type derivative 5a, and pyridinium/2-morpholinone-type derivative 6a. Among the assessed compounds, cis-3c, cis-3d, trans-3e, trans-3h, cis-3l, cis-4e, cis-4f, trans-4f, and cis-5a were found to inhibit HIV-1 reverse transcriptase (HIV-RT), HIV-1 protease (HIV-PR), and HCV NS5B polymerase (HCV NS5B), with IC50 values observed in the micromolar range. Cellular uptake of pyridinium/ethyl ester-type derivatives was higher than that of corresponding pyridinium/carboxylic acid-type derivatives and pyridinium/amide-type derivatives. This result might indicate that pyridinium/ethyl ester-type derivatives are expected to be lead compounds for multitargeting drugs to treat HIV/HCV coinfection.