Synthesis, reaction and antimicrobial activity of some pyridinethione derivatives containing benzimidazole nucleus

Cyanopyridinethione derivatives 3a,b were reacted with active halogen containing compounds in basic medium to afford the corresponding thienopyridine derivatives 4a,b, 5a,b, 6a,b. 3-Aminothieno[2,3-b]pyridine-2-carbonitrile 4a was converted to several pyridothienopyrimidin derivatives 10-15. Aminothienopyridine carbohydrazide 9 was converted to several triazolyl-, oxadiazolyl- and pyrazolyl- derivatives. Finally, compound 9 reacted with cyanoguanidine followed by NaOH to give aminothienopyridin-1,2,4-triazolyl-guanidine 26 which reacted with aromatic aldehydes and aliphatic acids to give the corresponding triazolo[1,5-a][1,3,5]triazin-2-yl)thieno[2,3-b]pyridin-3-amine derivatives 27a,b and 28a,b respectively.