Steric fixation of bromovinyluracil: Synthesis of furo[2,3‐d]pyrimidine nucleosides

Abstract
A new synthetic procedure for the preparation of 5,6‐dihydrofuro[2,3‐d]pyrimidin‐2(3H)‐one (3) and its deoxyriboside 8 is reported. Compound 3 undergoes nucleophilic reactions with various agents to yield 5‐substituted uracil derivatives. The dehydro derivative of 3, furo[2,3‐d]pyrimidin‐2(3H)‐one (18) was synthesized by cyclization of BVU 15, which made us develop a reproducible and high yield method for the synthesis of BV(D)U. Starting from 18, the α‐deoxyriboside 20 and the β‐riboside 22 were prepared.