REGIOSELECTIVE SYNTHESIS OF SUBSTITUTED THIENOPYRIMIDINES AND PYRIDOTHIENOPYRIMIDINES AND THEIR SELENOPHENO ANALOGS FROM 3-CYANOPYRIDINE-2(1H)-THIONES, 3-CYANOPYRIDINE-2(1H)-SELENONES, AMD N-CYANOCHLORACETAMIDINE

Article abstract of DOI:10.1007/BF01164746

3-Cyanopyridine-2(1H)-thiones and 3-cyano-2(1H)-selenones undergo heteroannelation with N-cyano-chloracetamidine to give thieno<2,3-b>pyridines, selenopheno<2,3-b>pyridines, 2,4-diaminopyrido-<3',2':4,5>thieno<3,2-d>pyrimidines, and 2,4-diaminopyrido<3',2';4,5>selenopheno<3,2-d>pyrimidines, which were converted to compounds containing triazine, aminopyrimidine, and pyrimidinedione rings.