AIDS-142016 AIDS142016 NSC658703 Ophiobolin A lactone Spiro[furan-2(3H),7'-[7H-3]oxacyclopenta[5,6]cycloocta[1,2,3-cd]pentalen]-4'(1'H)-one, 2',2'a,4,5,6',6'a,8',9',9'a,10',10'a,10'b-dodecahydro-1'-hydroxy-1',3,9'a-trimethyl-5-(2-methyl-1-propenyl)-, (4a'E)-