3,5-diacetoxy-9-[4-allyloxy-2,5,8-tris-methoxymethoxy-3,7-dimethyl-6-(2-trimethylsilanyl-ethoxycarbonylamino)-naphthalen-1-yl]-4,6,8-trimethyl-9-oxo-2-[2,2,5-trimethyl-6-(1-methyl-2-oxo-ethyl)-[1,3]dioxan-4-yl]-non-7-enoic acid allyl ester