5-[2-(tert-Butyl-dimethyl-silanyloxy)-eth-(Z)-ylidene]-3-[(1E,3E)-5-(tert-butyl-dimethyl-silanyloxy)-penta-1,3-dienyl]-5H-furan-2-one

(S)-5-[(S)-2-(tert-Butyl-dimethyl-silanyloxy)-1-hydroxy-ethyl]-3-[(1E,3E)-5-(tert-butyl-dimethyl-silanyloxy)-penta-1,3-dienyl]-5H-furan-2-one