Abstract
A number of thieno [3,2-b] pyrimidines are regioselectively synthesized in good yields from 5-(4- aryloxybut-2-ynylthio) via sulfoxide rearrangement/tandem cyclization protocol by the treatment of the sulfides with one equivalent of m-CPBA in chloroform at 0-5°C with stirring the reaction mixture at room temperature for 2 h.
Keywords: 5-Mercaptouracil, tandem reaction, [2,3] sigmatropic rearrangement, [3,3] sigmatropic rearrangement, thienopyrimidine