2-Methylpropenoic acid [[(1R)-1,2,3,4,4a,4bα,5,6,10,10aα-decahydro-1,4aβ-dimethyl-7-(1-methylethyl)phenanthren]-1α-yl]methyl ester

[1R-(1alpha,4abeta,4balpha,10aalpha)]-[1,2,3,4,4a,4b,5,6,10,10a-decahydro-7-isopropyl-1,4a-dimethyl-1-phenanthryl]methyl methacrylate