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