(4R,6R,7S)-9,9-dimethyl-5,8,10-trioxatricyclo[5.4.0.04,6]undec-1-en-3-one

(1S,2R,4S,6R,7S)-4-methoxycarbonyl-3,8-dioxatricyclo[5.1.0.02,4]octan-6-ol

(1R,2S,4S,5R,7R)-7-hydroxymethyl-3,8-dioxatricyclo[5.1.0.02,4]octan-5-ol

(4R,6R,7S)-2-iodo-9,9-dimethyl-5,8,10-trioxatricyclo[5.4.0.04,6]undec-1-en-3-one

(1R,5S,6R)-4-(tert-butyldimethylsiloxymethyl)-5-hydroxy-7-oxabicyclo[4.1.0]hept-3-en-2-one