4-((1R,4S,6R)-2,2,6-Trimethyl-4-trimethylsilanyloxy-7-oxa-bicyclo[4.1.0]hept-1-yl)-but-3-yn-2-ol

2,2-Dimethyl-propionic acid (1R,3S,6R)-6-ethynyl-1,5,5-trimethyl-7-oxa-bicyclo[4.1.0]hept-3-yl ester

4-[(1R,4S,6R)-4-(tert-Butyl-dimethyl-silanyloxy)-2,2,6-trimethyl-7-oxa-bicyclo[4.1.0]hept-1-yl]-but-3-yn-2-ol