{(2S,3R)-5-Hydroxy-2-[(R)-(4-methoxy-benzyloxy)-((4S,5R)-2,2,5-trimethyl-[1,3]dioxolan-4-yl)-methyl]-tetrahydro-furan-3-yl}-acetic acid tert-butyl ester

Acetic acid (E)-2-oxo-4-((4R,5R)-2,2,5-trimethyl-[1,3]dioxolan-4-yl)-but-3-enyl ester

(4R,5R,6R)-6-(tert-Butyl-dimethyl-silanyloxy)-2,2,4-trimethyl-1,3-dioxa-spiro[4.4]non-8-en-7-one

(4R,5R,6R)-6-(tert-Butyl-dimethyl-silanyloxy)-2,2,4-trimethyl-1,3-dioxa-spiro[4.4]nonan-7-one

(4R,5S)-5-[(R)-(tert-Butyl-dimethyl-silanyloxy)-((4S,5R)-2,2,5-trimethyl-[1,3]dioxolan-4-yl)-methyl]-4-vinyl-dihydro-furan-2-one