(2R,3S,4aR,6R,7R,8aS)-2-(hydroxymethyl)-6-(phenylsulfonylmethyl)octahydropyrano[3,2-b]pyran-3,7-diol benzylidene acetal 、
乙酸酐 在
吡啶 作用下,
以96%的产率得到(2R,3R,4aS,6R,7S,8aR)-7-hydroxy-6-(hydroxymethyl)-2-(phenylsulfonylmethyl)octahydropyrano[3,2-b]pyran-3-yl acetate benzylidene acetal