Showing structure for methyl (6ar,7s,10ar)-3-{[(2s,4r,5s,6r)-4,5-dihydroxy-6-methyloxan-2-yl]oxy}-6a,7,10a,12-tetrahydroxy-8-methoxy-1-methyl-6,10,11-trioxo-7h-tetracene-2-carboxylate