6-methyl-7,8-dihydro-6H-spiro[1,3-dioxolo[4,5-g]isoquinoline-5,2'-indene]-1',3'-dione InChI=1/C19H15NO4/c1-20-7-6-11-8-15-16(24-10-23-15)9-14(11)19(20)17(21)12-4-2-3-5-13(12)18(19)22/h2-5,8-9H,6-7,10H2,1H spiro[1,3-dioxolo[4,5-g]isoquinoline-5(6H),2'-[2H]indene]-1',3'-dione, 7,8-dihydro-6-methyl-