(2R,3S)-3-(tert-Butyl-dimethyl-silanyloxy)-7-hydroxy-2-methyl-heptanoic acid (2R,3R,5S)-5-[(2R,3R,4R)-3-(tert-butyl-dimethyl-silanyloxy)-2-methoxy-4-methyl-tetrahydro-pyran-2-yl]-2-vinyl-tetrahydro-furan-3-yl ester

(2R,3S)-3-(tert-Butyl-dimethyl-silanyloxy)-7-(4-methoxy-benzyloxy)-2-methyl-heptanoic acid (2R,3R,5S)-5-[(2R,3R,4R)-3-(tert-butyl-dimethyl-silanyloxy)-2-methoxy-4-methyl-tetrahydro-pyran-2-yl]-2-vinyl-tetrahydro-furan-3-yl ester