(3aR,4S,5R,7R,8S)-5-((tert-butyldimethylsilyl)oxy)-7-isopropyl-1,4-dimethyl-2,3,3a,4,5,6,7,8-octahydro-4,7-epoxyazulen-8-ol

(-)-englerin B

3-甲基-2-丁酮

(1R,3aR,4S,7R,8S,8aR)-8-hydroxy-7-isopropyl-1,4-dimethyloctahydro-4,7-epoxyazulen-5(1H)-one

(1R,3aR,4S,5R,7R,8S,8aR)-5-((tert-butyldimethylsilyl)oxy)-7-isopropyl-1,4-dimethyldecahydro-4,7-epoxyazulen-8-ol