(6S)-6-benzyloxy-4-hydroxy-6-oxo-7-[(2R,4S,6R)-(2-phenyl-6-triisopropylsilanyloxymethyl-[1,3]dioxan-4-yl)]hept-4-enyl-2,2-dimethylpropionate

(2S,4S,6R,8R,10S)-10-(tert-butyldimethylsilanyloxy)-4-methoxy-8-triisopropylsilanyloxymethyl-1,7-dioxaspiro[5.5]undec-2-ylmethyl 2,2-dimethylpropionate