Synthesis of pyrido[3',2';4,5]thieno[2,3-e][1,2,4]triazolo[4,3-a]pyrimidin-5(4ZZ)-one derivatives

摘要

Some new pyrido[3',2';4,5]thieno[2,3-e]-[1,2,4]triazolo[4,3-a]pyrimidin-5(4H)-ones were prepared through heterocyclization of ethyl 3-amino-thieno[2,3-b]pyridine-2-carboxylate with phenyl or ethyl isothiocyanate followed by nucleophilic displacement with hydrazine,and finally cyclocondensa-tion with orthoesters.