4,8-Ethenopyrrolo[3,4-f]isoindole-9-carboxylic acid, 1,2,3,3a,4,4a,5,6,7,7a,8,8a-dodecahydro-8,10-dimethyl-1,3,5,7-tetraoxo-, ethyl ester AIDS-138990 AIDS138990 NSC646934