-nucleosides having furanoid structures, or between C-1′ and C-5′ to yield pyranoid compounds. Each reaction can yield one of the two possible anomers or a mixture of both. We have dehydrated pentahydroxypentyl-heterocycles having d - gluco , d - manno , and d - galacto configurations. When the reactions were kinetically controlled, the 6,6-dimethyl-2-(pentitol-1-yl)-4,5,6,7-tetrahydroindol-4-ones having
摘要酸催化五羟基戊基杂环可在C-1'和C-4'之间生成具有
呋喃结构的C-核苷,或在C-1'和C-5'之间生成
吡喃类化合物。每个反应可产生两种可能的端基异构体之一或两者的混合物。我们已经脱
水了具有d-
葡萄糖,d-manno和d-galacto构型的五羟基戊基杂环。当动力学控制反应时,具有d-
葡萄糖或d-
甘露聚糖构型的6,6-二甲基-2-(
戊醇-1-基)-
4,5,6,7-四氢吲哚-4-酮产生2- α-d-阿拉伯
呋喃糖基-6,6-二甲基-
4,5,6,7-四氢吲哚-4-一,但它们产生了2-α-d-阿拉伯
吡喃糖基-6,6-二甲基-4,5,6,7 -四氢
吲哚-4-酮在热力学控制的条件下。3-乙酰基-2-甲基-5-(d-半
乳糖-
戊醇-1-基)-1-丙基
吡咯的脱
水得到3-乙酰基-5-(α-和β-d-
吡喃
吡喃糖基)-2-的混合物甲基-1-丙基
吡咯。这些结果与涉及中间C-1'碳正离子化的机理是一致的。