C=C(C(=O)OC)[C@@H]1CC[C@@](C)(O)[C@@H](OC(C)=O)CC/C(C)=C/CC[C@]2(C)O[C@H]2C1 methyl 2-((1S,3R,6R,7S,10E,14S)-7-(acetyloxy)-6-hydroxy-6,10,14-trimethyl-15-oxabicyclo[12.1.0]pentadec-10-en-3-yl)prop-2-enoate