The Development of new Methods for the Deoxygenation of Sugars

糖的脱氧作用在碳水化合物化学中占有重要地位。虽然已经有许多方法通过各种中间体来脱氧，但关于经常用于糖化学的乙酰化糖脱氧的令人满意的方法的报道很少。然后，我们研究了将糖化合物转化为脱氧糖的新的有效途径。三苯基硅烷是一种很好的脱氧剂，可以将乙酰化糖转化为脱氧糖。脱氧的优点是，由于反应在中性条件下进行，乙酰化糖可以在不影响缩醛等其他官能团的情况下脱氧。对二(二苯基氢硅基)苯是一种很好的脱氧剂，与三苯基硅烷相比，脱氧剂用量少，脱氧完全。此外，生成的脱氧糖可以很容易地从反应混合物中分离出来，因为试剂的副产物是高沸点的化合物。

Deoxygenation of sugars occupies a significant position in carbohydrate chemistry. Although there have been numerous methods for the deoxygenation via various intermediates, reports of satisfactory methods for the deoxygenation of acetylated sugars, which were often utilized in sugar chemistry, are rare. We have then investigated new efficient routes for the transformation of sugar compounds to deoxysugars.1. Triphenylsilane is a good deoxygenating reagent for the transformation of acetylated sugars to deoxysugars. The deoxygenation has a advantage that the acetylated sugars can be deoxygenated without affecting the other functinalities such as acetals, since the reaction proceeds under neutral conditions.2. p-bis(diphenylhydrosilyl)benzene is a excellent reducing reagent for the deoxygenation of acetylated sugars, since the deoxygenation proceeds completely with less amount of the reducing agent compared with the case of triphenylsilane. Furthermore, the resulting deoxysugars can be easily isolated from the reaction mixture, since the by-products derived from the reagent are high boiling compounds.