phenoxy-acetic acid 1-{5-(2-allyloxycarbonylamino-ethyl)-2-[4-(tert-butyl-dimethyl-silanyloxy)-phenyl]-5-[2-(3-ethyl-6-oxo-3,6-dihydro-2H-pyran-2-yl)-vinyl]-[1,3]dioxolan-4-ylmethyl}-5-[3-(4-methoxy-phenoxymethoxy)-cyclohexyl]-penta-2,4-dienyl ester