Showing structure for methyl (1r,13r,16s,18r)-4,10-dihydroxy-7-methoxy-13,17,17-trimethyl-12-oxapentacyclo[11.4.1.0²,¹¹.0³,⁸.0¹⁶,¹⁸]octadeca-2,4,6,8,10-pentaene-5-carboxylate