2-oxocorynoxan-17-al InChI=1/C19H24N2O2/c1-2-13-12-21-9-8-19(17(21)11-14(13)7-10-22)15-5-3-4-6-16(15)20-18(19)23/h3-6,10,13-14,17H,2,7-9,11-12H2,1H3,(H,20,23 spiro[3H-indole-3,1'(5'H)-indolizine]-7'-acetaldehyde, 6'-ethyl-1,2,2',3',6',7',8',8'a-octahydro-2-oxo-