摘要用四氧化将顺式-2,3-二脱氧-4,5-O-异亚丙基-2-C-甲基-dl-甘油-戊-2-烯酸酯(1)羟化,得到4,5-O-异亚丙基乙基-β-dl-半乳糖苷(4,5- O-异亚丙基-2-C-甲基-dl-lyxonate,3)和4,5- O-异亚丙基-α-dl-葡萄糖苷(乙基4,5- O -异亚丙基-2-C-甲基-dl-核糖酸酯,4)。类似地,1的反式异构体产生4,5-O-异亚丙基-α-dl-半乳糖苷酸乙酯(4,5-O-异亚丙基-2-C-甲基-dl-木糖酸乙酯,5)的混合物4,5-O-异亚丙基-β-dl-葡糖精(4,5-O-异亚丙基-2-C-甲基-dl-阿拉伯糖酸酯,6)。化合物3–6被转化为相应的1,4-内酯。
Green aldose isomerisation: 2-C-methyl-1,4-lactones from the reaction of Amadori ketoses with calcium hydroxide
摘要:
Saccharinic acids, branched 2-C-methyl-aldonic acids, may be accessed via a green procedure from aldoses by sequential conversion to an Amadori ketose and treatment with calcium hydroxide; D-galactose and D-glucose are converted to 2-C-methyl-D-lyxono-1,4-lactone (with a small amount of 2-C-methyl-D-xylono-1,4-lactone) and 2-C-methyl-D-ribono-1,4-lactone. Inversion of configuration at C-4 of the branched lactones allows access to 2-C-methyl-L-ribono-1,4-lactone and 2-C-methyl-L-lyxono-1,4-lactone, respectively. D-Xylose affords 2-C-methyl-D-threono-1,4-lactone and 2-C-methyl-D-erythrono-1,4-lactone, whereas L-arabinose, under similar conditions, gave the enantioiners 2-C-methyl-L-lactone-1,4-lactone and 2-C-methyl-L-erythrono-1,4-lactone. (c) 2006 Published by Elsevier Ltd.
[EN] PROCESS FOR PREPARING SACCHARINIC ACIDS AND LACTONES<br/>[FR] PROCEDE DE PREPARATION D'ACIDES SACCHARINIQUES ET DE LACTONES
申请人:CHANCELLORS MASTERS AND SCHOLA
公开号:WO2007025304A2
公开(公告)日:2007-03-01
[EN] An improved process for preparing a saccharinic acid or lactone is disclosed that utilizes the well-known Amadori rearrangement reaction. The synthesis utilizes protected or unprotected sugars or their analogues as starting materials, and reagents not previously utilized to afford increased product yields in decreased reaction time. [FR] L'invention concerne un procédé amélioré de préparation d'acide saccharinique ou de lactone, qui utilise la réaction bien connue de réarrangement d'Amadori. Le procédé de synthèse utilise comme matières premières des sucres protégés ou non protégés ou leurs analogues, ainsi que les réactifs n'ayant pas été utilisés précédemment pour obtenir des rendements de produit accrus en un temps de réaction réduit.