72548-16-4 Acantholide NSC 277282 Propanoic acid, 2-methyl-, 6-formyl-2,3,3a,4,5,8,9,11a-octahydro-4-hydroxy-10-methyl-3-methylene-2-oxocyclodeca(b)furan-5-yl ester, (3aR-(3aR*,4S*,5S*,6E,10E,11aR*))-