(2S,4R)-1-[(4R,6R)-6-(2-Benzyloxy-ethyl)-2,2-dimethyl-[1,3]dioxan-4-yl]-5-{(4S,6S)-6-[(S)-2-(tert-butyl-dimethyl-silanyloxy)-2-((4R,5R)-2,2-dimethyl-4-pentyl-[1,3]dioxan-5-yl)-ethyl]-2,2-dimethyl-[1,3]dioxan-4-yl}-pentane-2,4-diol