4b,1-(Epoxymethano)-4H,10H-3,9-dioxapentaleno[1',6':2,3,4]cyclobuta[1,2-a]naphthalene-4,10(1H)-dione, 2,2a,4a,10b-tetrahydro-1,4a,5,12-tetramethyl- AIDS-144068 AIDS144068 NSC666108