protease subtilisin in anhydrousdimethylformamide in the presence of the activated ester trifluoroethyl butanoate. Under the reaction conditions used, all the substrates were converted into the corresponding monobutanoates in ca. 50% isolated yields. Structural determination of the products by 13C NMR indicated a strong preference of subtilisin towards the regioselectiveesterification of the primary hydroxyls
在活化的酯三氟乙基丁酸酯的存在下,在无水二甲基甲酰胺中,蛋白酶枯草杆菌蛋白酶将几种含有D-果糖部分的二糖和寡糖酰化。在所用的反应条件下,所有底物在约2℃下转化为相应的单丁酸酯。分离产率为50%。如通过蔗糖已经观察到的,通过13 C NMR对产物进行结构确定表明枯草杆菌蛋白酶对果糖部分的伯羟基,特别是C-1 OH的区域选择性酯化具有强烈的偏好。
Highly Efficient Catalytic Activity of Lanthanide(III) Ions for Conversion of Saccharides to 5-Hydroxymethyl-2-furfural in Organic Solvents
作者:Kei-ichi Seri、Yoshihisa Inoue、Hitoshi Ishida
DOI:10.1246/cl.2000.22
日期:2000.1
All lanthanide(III) ions were found to catalyze dehydration of saccharides to 5-hydroxymethyl-2-furfural (HMF) in DMSO at 100 - 120 °C. Particularly, d-fructose was almost quantitatively converted to HMF without generating any byproducts. The results of the reaction with di- and trisaccharides indicated that the d-fructose moiety in the substrates was selectively converted to HMF.