Carbanions in Carbohydrate Chemistry: Synthesis of C-Glycosyl Malonates
Carbanions in Carbohydrate Chemistry: Synthesis of C-Glycosyl Malonates
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碳水化合物化学中的碳负离子：C-糖基丙二酸酯的合成
DOI：
10.1139/v74-197
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发表时间：
1974
影响因子：
1.1
通讯作者：
A. Pernet
中科院分区：
文献类型：
--
作者：
S. Hanessian;A. Pernet
2，3，4，6-四-O-乙酰基-β-D-吡喃葡萄糖基溴与丙二酸二乙酯钠缩合，得到结晶的2-（2，3，4，6-四-O-乙酰基-β-D-吡喃葡萄糖基）丙二酸二乙酯。相应的二苄基酯被证明是制备结晶β-D-吡喃葡萄糖基丙二酸和β-D-吡喃葡萄糖基乙酸衍生物的通用中间体。在这些C-糖苷的端基异构体的配置确定的化学相关性。与2，3，4，6-四-O-乙酰基- β-D-吡喃葡萄糖酰氯和丙二酸二乙酯钠反应，主要产物是碳负离子进攻1，2-乙酰氧鎓离子而生成的1，2-O-缩酮衍生物。本文报道了溴化2，3，4，6-四-O-苄基-α-D-吡喃葡萄糖与丙二酸二乙酯钠在溴离子存在和不存在下的缩合反应，并对反应机理进行了讨论。还制备了D-甘露呋喃糖系列的C-糖苷，并描述了它们转化为D-来苏呋喃糖系列（异头混合物）。
The condensation of 2,3,4,6-tetra-O-acetyl-α-D-glucopyranosyl bromide with sodio diethyl malonate led to crystalline diethyl 2-(2,3,4,6-tetra-O-acetyl-β-D-glucopyranosyl) malonate. The corresponding dibenzyl ester proved to be a versatile intermediate for the preparation of crystalline β-D-glucopyranosyl malonic acid and β-D-glucopyranosyl acetic acid derivatives. The anomeric configuration in these C-glycosides was determined by a chemical correlation. With 2,3,4,6-tetra-O-acetyl- β-D-glucopyranosyl chloride and sodio diethyl malonate, the major product was a 1,2-O-ketal derivative resulting from an attack of the carbanion on the 1,2-acetoxonium ion. The condensation of 2,3,4,6-tetra-O-benzyl-α-D-glucopyranosyl bromide with sodio diethyl malonate was conducted with, and without added bromide ion and the mechanistic implications of the results are discussed. C-Glycosides were also prepared in the D-mannofuranose series and their transformation into the D-lyxofuranose series (anomeric mixture) is described...