Methanesulfonic acid (2R,3S,4R)-4-benzyloxy-2-(tert-butyl-dimethyl-silanyloxymethyl)-3,4-dihydro-2H-pyran-3-yl ester

(E)-(4R,5R)-5-Benzyloxy-6-[1,3]dithian-2-yl-4-methanesulfonyloxy-hex-2-enoic acid ethyl ester