2,2-Dimethyl-propionic acid (1R,2R,3R,4S)-8-oxo-3-((4R,5R)-2,2,5-trimethyl-[1,3]dioxolan-4-yl)-bicyclo[2.2.2]oct-5-en-2-ylmethyl ester

(1S,4S,5R,6R,8R)-8-(tert-Butyl-dimethyl-silanyloxy)-5-(4-methoxy-benzyloxymethyl)-6-((4R,5R)-2,2,5-trimethyl-[1,3]dioxolan-4-yl)-bicyclo[2.2.2]octan-2-one

2,2-Dimethyl-propionic acid (1S,2R,3R,4S,7R)-5-oxo-7-p-tolyloxythiocarbonyloxy-3-((4R,5R)-2,2,5-trimethyl-[1,3]dioxolan-4-yl)-bicyclo[2.2.2]oct-2-ylmethyl ester

(1S,2S,4S,5R,6R,8R)-8-(tert-Butyl-dimethyl-silanyloxy)-5-hydroxymethyl-6-((4R,5R)-2,2,5-trimethyl-[1,3]dioxolan-4-yl)-bicyclo[2.2.2]octan-2-ol

(1S,4R,7R,8R)-8-Hydroxymethyl-7-((4R,5R)-2,2,5-trimethyl-[1,3]dioxolan-4-yl)-bicyclo[2.2.2]oct-5-en-2-one