1-[(4R,5S,6R)-6-((S)-1-{2-[(2R,3S,4R)-2,4-Bis-(tert-butyl-dimethyl-silanyloxy)-3,5-dimethyl-hexyl]-[1,3]dithian-2-yl}-ethyl)-2,2,5-trimethyl-[1,3]dioxan-4-yl]-propynone