Syntheses of Carbocyclic Analogs of Nucleoside and Bioactive Pseudo-Sugars from Carbohydrate

在高效利用天然丰富的碳水化合物的研究过程中，我们开发了多种多样的转化方法，从碳水化合物到旋光性伪六吡喃糖和伪五氟喃糖。此外，在对伪硝基呋喃糖化学行为的研究中，提出了一种合成旋光性伪氨基糖的新方法。我们还发现，以亚硝基烯烃衍生物的michael型加成反应为关键反应，可以成功地合成伪糖苷，如碳环核苷类似物。在这些反应途径中，初始己糖和c - 2,3,4（伪己糖衍生物）或c - 3,4（伪五戊糖衍生物）取代基的所有6个碳及其构型都被保留了下来。作为这些合成研究的延伸，我们已经将d -葡萄糖和d -葡萄糖醛酸内酯转化为旋光性伪六吡喃糖：伪α - d -葡萄糖醛酸糖和伪β - l -异吡喃糖，以及旋光性伪五氟糖：伪α -和- β - d -阿拉伯糖醛酸糖和伪β - l -木糖呋喃糖。此外，生物活性伪氨基糖：validamine， epi-validamine和valienamine，已经通过假己糖合成中常用的反应中间体合成。此外，我们还制备了三种新的核苷类旋光性环己烷类似物：(-)-9-伪β - d -glucopyranosyladenine，(-)-9-伪β - l -idopyranosyladenine，并合成了核苷类旋光性环戊烷类似物：(+)- cycloadine, (-)-aristeromycin和(+)-9-伪β - l -xylofuranosyladenine，这些核苷类旋光性类似物具有抗病毒和抗肿瘤等重要的生物活性。

During the course of studies on highly effective utilization of naturally abundant carbohydrates, we have developed versatile conversion methods starting from carbohydrates leading to optically active pseudo-hexopyranoses and pseudo-pentafuranoses. Furthermore, in the examination of the chemical behavior of pseudo-nitrofuranoses, a new synthetic method for optically active pseudo-aminosugars has been developed. We have also found that pseudo-glycosides such as carbocyclic nucleoside analogs are successfully synthesized by use of Michael-type addition reactions to nitro-olefin derivatives as key reactions. In these reaction pathways, all six carbons of initial hexoses and substituents at C-2, 3, 4 (in pseudo-hexopyranose derivatives) or at C-3, 4 (in pseudo-pentafuranose derivatives) with their configurations, have been preserved.As an extension of these synthetic studies, we have converted D-glucose and D-glucuronolactone to optically active pseudo-hexopyranoses : pseudo-alpha-D-glucopyranose and pseudo-beta-L-idopyranose and optically active pseudo-pentafuranoses : pseudo-alpha- and -beta-D-arabinofuranoses and pseudo-beta-L-xylofuranose. Furthermore, bioactive pseudo-aminosugars : validamine, epi-validamine, and valienamine, have been synthesized via common reaction intermediates used in pseudo-hexopyranose synthesis. In addition, we have prepared three new optically active cyclohexane analogs of nucleoside : (-)-9-pseudo-beta-D-glucopyranosyladenine, (-)-9-pseudo-beta-L-idopyranosyladenine, and also have synthesized optically active cyclopentane analogs of nucleoside : (+)-cyclaradine, (-)-aristeromycin, and (+)-9-pseudo-beta-L-xylofuranosyladenine which are known to exhibit various important bioactivity such as antiviral and antitumor.