2-(6-(4,4,7,9a-Tetramethyl-2,3,3a,4,4a,5,6,8a,9,9a-decahydronaphtho[2,3-b]furan-2-yl)-6-methyl-1,2-dioxan-3-yl)propanoic acid AIDS-132141 AIDS132141 NSC625517 Trunculin B