Compelling evidence for a stepwise mechanism of the alkaline cyclisation of uridine 3 '-phosphate esters

: Lonnberg H, Stromberg R, Williams A

Publisher: ROYAL SOC CHEMISTRY

: 2004

Organic and Biomolecular Chemistry

ORGANIC & BIOMOLECULAR CHEMISTRY

: ORG BIOMOL CHEM

: 2

: 15

: 2165

: 2167

: 3

: 1477-0520

DOI: https://doi.org/10.1039/b406926a

A Bronsted graph with a convex break at pK(a) (Lg) = 12.58 provides compelling evidence for an intermediate in the alkaline cyclisation of uridine 3'-phosphate esters. The transient pentacoordinated oxyphosphorane dianion intermediate collapses to reactant and cyclic uridine 2', 3'-monophosphate faster than it can pseudo-rotate and isomerise to the 2'-isomer.

Chemical sciences