Stereoselective cyclization of (Z)-(2R,3R,4R)-6-cyclohexyloxy-1,3,4-tribenzyloxy-5-hexen-2-ol (1)promoted by Hg(OCOCF3)2, followed by reductive work up gave the 2-deoxy-α-hexopyranoside derivative almost exclusively. On the other hand, a predominant formation of the β-anomer was achieved by the treatment of 1 with PhSeCl, and the successive deselenation.
在 Hg(OCOCF3)2 的促进下,(Z)-(2R,3R,4R)-6-环己氧基-1,3,4-三苄氧基-
5-己烯-2-醇(1)发生立体选择性环化,然后进行还原反应,几乎只得到 2-脱氧-α-己
吡喃糖苷衍
生物。另一方面,用 PhSeCl 处理 1 并连续进行脱
硒反应,可主要生成 β-异构体。