13164-90-4 9-Epimitomycin B Azirino(2',3':3,4)pyrrolo(1,2-a)indole-4,7-dione, 1,1a,2,8,8a,8b-hexahydro-8-(((aminocarbonyl)oxy)methyl)-1,5-dimethyl-8a-hydroxy-6-methoxy-, (1aS-(1a-alpha,8-beta,8a-alpha,8b-alpha))-