Synthesis and Biological Evaluation of 2-(2-Deoxy-β-D-ribofuranosyl)pyridine-4-carboxamide

A new protected 2-deoxy-D -ribose derivative, 5-O-(tert-butyl)diphenylsilyl]-2-deoxy-3,4-O- isopropylidene-aldehydo-D -ribose ( 5 ), was synthesized starting from 2-deoxy-D -ribose. This compound was coupled with 2-lithio-4-(4,5-dihydro-4,4-dimethyloxazol-2-yl)pyridine giving a D /L -glycero-mixture 7 of 5-O-(tert-butyl)diphenylsilyl]-2-deoxy-1-C-4-(4,5 -dihydro-4,4-dimethyloxazol-2-yl)pyridin-2-yl]-3,4-O-isopropylidene- D -erythro-pentitol. The mixture 7 was 1-O-mesylated with methanesulfonyl chloride and subsequently treated with CF₃COOH/H₂O and ammonia to afford the α/β-D -anomers 10 of 2-(2-deoxy-D -ribofuranosyl)pyridine-4-carboxamide. Both anomers were purified and separated by HPLC and identified by NMR and DCI-MS. Anomer β-D - 10 was evaluated against a series of tumor-cell lines and a variety of viral strains. No antitumor or antiviral activity was observed.