Regioselective Mitsunobu Reaction of Partially Protected Uridine
Maurycy Szlenkier1, Karol Kamel1, Jerzy Boryski1
1a Institute of Bioorganic Chemistry, Polish Academy of Sciences , Poznan , Poland.
Abstract:
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.
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