[(3aR,5S,6R,6aR)-5-((S)-2,2-Dimethyl-[1,3]dioxolan-4-yl)-2,2-dimethyl-6-vinyl-tetrahydro-furo[2,3-d][1,3]dioxol-6-yl]-acetaldehyde

[(3aR,5S,6aR)-5-((S)-2,2-Dimethyl-[1,3]dioxolan-4-yl)-2,2-dimethyl-dihydro-furo[2,3-d][1,3]dioxol-(6Z)-ylidene]-acetic acid ethyl ester