31616-01-0

The invention discloses a (2 'R) -2' - deoxy -2 '- fluoro -2' - methyl urea glucoside (type I) synthetic method. Cheap and easily available starting material, through the hydroxyl protection, cyclization, the links such as fluoride, obtains the type I compound. (by machine translation)

Mitsunobu reaction of partially acylated uridine proceeds with high regioselectivity for intramolecular SN2 anhydro linkage closuring. Under the reaction conditions, an isomeric mixture of diacyl uridine derivatives with either free 2′- or 3′-hydroxyl group was transformed into a single cyclonucleosidic product, 2,2′-anhydro-3′,5′-di-O-acyluridine. This paper presents a possible mechanism of the reactions, the explanation of observed phenomenon based on semiempirical and density functional theory (DFT) calculations and possible utility of this synthetic pathway.

(Chemical Equation Presented) Several 2′,3′-dideoxynucleosides (ddNs) and 2′,3′-didehydro-2′,3′-dideoxynucleosides (d4Ns) are FDA-approved anti-HIV drugs. Via conveniently synthesized 2,2′-anhydronucleosides, we have developed a novel synthesis of d4Ns by discovering and applying a new telluride-mediated elimination reaction. Our experiment results show that after substitution of 2,2′-anhydronucleosides with a telluride monoanion, a telluride intermediate is formed, and its elimination leads to formation of the olefin products (d4Ns). Our mechanistic study indicates that this telluride-assisted reaction consists of two steps: substitution (or addition) and elimination. By using dimethyl ditelluride (0.1 equiv) as the reagent, d4Ns can be synthesized with yields up to 90% via this telluride-mediated elimination. Our novel strategy has great potential to simplify synthesis of these drugs and to further reduce cost of AIDS treatment and will also facilitate development of novel d4N and ddN analogues.

The 1,2-propadienyl (allenyl) group was introduced by means of a radical reaction at the 2'-α- C position of uridine to prepare the rifle compound as a novel analogue of 2'-azido-2'-deoxyuridine, a known inhibitor of RDPR.

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