Synthesis and anti-HBV activity of carbocyclic nucleoside hybrids with salient features of entecavir and aristeromycin.

Modified carbocyclic nucleosides (4a-g) constituting 7-deazapurine, 4'-methyl, exocyclic double bond and 2',3'-hydroxy were synthesized. NOE and X-ray studies of 4c confirmed the α-configuration of 4'-methyl. The anti-HBV assay demonstrated 4e (IC50 = 3.4 µM) without notable cytotoxicity (CC50 = 87.5 µM) as a promising lead for future exploration.