4-(tert-butyl-dimethyl-silanyloxy)-6-[12-(tert-butyl-dimethyl-silanyloxy)-14-(4-methoxy-benzyloxy)-2,6-bis-methoxymethoxy-5,7,9,11,13,15-hexamethyl-nonadeca-3,8,16,18-tetraenyl]-3,5-dimethyl-tetrahydro-pyran-2-one