乙酸酐 、
2-C-chlorodifluoromethyl-2-deoxy-3,4-di-O-[(R)-2,2,2-ethylidene-5(S),6-O-isopropylidene]-D-arabinohexopyranos-5-ulose 在
吡啶 作用下,
生成 1-O-acetyl-2-C-chlorodifluoromethyl-2-deoxy-3,4-di-O-[(R)-2,2,2-ethylidene-5(S),6-O-isopropylidene]-α-D-arabinohexopyranos-5-ulose 、 1-O-acetyl-2-C-chlorodifluoromethyl-2-deoxy-3,4-di-O-[(R)-2,2,2-ethylidene-5(S),6-O-isopropylidene]-β-D-arabinohexopyranos-5-ulose