11H-3(3H)-Oxo-5,6-dihydropyrano(3,2-a)carbazole 127040-35-1 6,11-Dihydropyrano(3,2-a)carbazol-3(5H)-one BRN 4256085 Pyrano(3,2-a)carbazol-3(5H)-one, 6,11-dihydro-