4-(tert-butyl-dimethyl-silanyloxy)-6-(5-{4-(tert-butyl-dimethyl-silanyloxy)-6-[2-(tert-butyl-dimethyl-silanyloxy)-3-methoxy-propyl]-2-methoxy-3,5-dimethyl-tetrahydro-pyran-2-yl}-2-oxo-[1,3]dioxolan-4-yl)-5-methoxy-hexanal