LAUSR

Abstract Indole-2-carboxylates are refluxed with hydrazine hydrate to form 5-substituted-3-phenylindole-2-carboxyhydrazides. These are again converted to corresponding indole-2-carboxyazides. Azides are further converted into carbamates and finally these carbamates are cyclized to form the respective substituted 6H, 11H-indolo [3,2-C] isoquinolin-2-ones ( 1a – c ). These ( 1a – c ) were reacted with phosphorus pentasulfide in refluxing pyridine to yield the respective thiones ( 2a – c ). These thiones ( 2a – c ) on reaction with chloroacetic acid and sodium acetate in acetic acid under refluxing temperature for 5 h yielded isoquinoline-thioacetic acids ( 3a – c ). Compounds ( 3a – c ) on reaction with orthopheneylene diamine dihydrochloride in ethylene glycol at refluxing temperature yielded substituted indolo [3,2-C] isoquinolin-2′-yl sulfanyl methylene benzimidazoles ( 4a – c ).