CC1=C2CC/C(C)=C/CC[C@@]3(C)O[C@@H]3CC/C(C)=C\[C@H]2OC1=O	(1R,2Z,6R,8R,11E)-3,8,12,16-tetramethyl-7,18-dioxatricyclo[13.3.0.0^{6,8}]octadeca-2,11,15-trien-17-one