(3S,4aR,8aS)-3-methoxymethoxy-hexahydro-pyrano[3,2-b]pyran-2-one

(2S,3S,2''R,3''S)-p-toluenesulfonic acid 3-[3''-(tert-butyldimethylsiloxy)tetrahydropyran-2''-yl-methyl]-oxiran-2-yl-methyl ester