Showing structure for ethyl (1'r,5's,6r,11's,12'r)-6-ethyl-6-methoxy-3'-methyl-9'-oxo-3'-azaspiro[oxane-3,15'-tetracyclo[6.5.1.1¹,⁵.0¹¹,¹⁴]pentadecan]-8'(14')-ene-12'-carboxylate