1,3-Dihydrospiro(2H-imidazo(4,5-b)pyridine-2,3'-(3H)indol)-2'(1'H)-one 40114-91-8 Spiro(2H-imidazo(4,5-b)pyridine-2,3'-(3H)indol)-2'(1'H)-one, 1,3-dihydro-