| Abstract
| - A novel modular and practical methodology for preparation of 6-substituted pyridin-3-yl C-nucleosideswas developed. The Heck reaction of 2-chloro-5-iodopyridine with a 3‘-TBDMS-protected glycal gavea 6-chloropyridin-3-yl nucleoside analogue, which was then desilylated, selectively reduced, and reprotectedto give the TBDMS-protected 6-chloropyridin-3-yl C-2‘-deoxyribonucleoside as a pure β-anomer in atotal yield of 39% over four steps. This key intermediate was then subjected to a series of palladium-catalyzed cross-coupling reactions, aminations, and alkoxylations to give a series of protected 1β-(6-alkyl-, 6-aryl-, 6-hetaryl, 6-amino-, and 6-tert-butoxypyridin-3-yl)-2‘-deoxyribonucleosides. 6-Unsubstitutedpyridin-3-yl C-nucleoside was prepared by catalytic hydrogenation of the chloro derivative and6-oxopyridine C-nucleoside by treatment of the 6-tert-butoxy derivative with TFA. Deprotection of allthe silylated nucleosides by Et3N·3HF gave a series of free C-nucleosides (10 examples).
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