(1R,2S,5R,6S,7S)-5-(2'-oxo-1'-propyl)-4,10-dioxatricyclo(5.2.1.O2,6)dec-8-ene

ethyl 2-(furan-2-yl)-4-hydroxy-6-oxo-4-phenylcyclohexanecarboxylate

吗啉

diethyl 7-oxabicyclo[2.2.1]hepta-2,5-diene-2,3-dicarboxylate