[4-(tert-butyl-dimethyl-silanyloxy)-6-(3-{6-[2-(2,2-dimethyl-[1,3]dioxolan-4-yl)-2-hydroxy-1-(2,4,6-triisopropyl-phenylselanyl)-ethyl]-3-methyl-tetrahydro-pyran-2-yl}-2-hydroxy-propyl)-tetrahydro-pyran-2-yl]-acetic acid methyl ester