9,12-EPOXY-1H-DIINDOLO[1,2,3-FG:3',2',1'-KL]PYRROLO[3,4-I][1,6]BENZODIAZOCINE-10-CARBOXYLIC ACID, 2-[(1,1-DIMETHYLETHYL)DIMETHYLSILYL]-2,3,9,10,11,12-HEXAHYDRO-10-METHOXY-9-METHYL-1-OXO-, METHYL ESTER, (9S,10R,12R)- (9CI)