名称:
A convenient access to the 1,5-anhydro forms of d-tagatose, l-rhamnulose and d-xylulose via 2-hydroxyglycal esters
摘要:
Zemplen methanolysis or a three-step protocol comprising hydroxylaminolysis, de-O-acetylation and deoximination smoothly and efficiently convert the benzoylated 2-hydroxy-D-glycals Of D-galactose, L-rhamnose and D-Xylose into their configurationally related 1,5-anhydro-ketoses, thereby providing convenient access to the 1,5-anhydro forms of D-tagatose, L-rhamnulose and D-Xylulose. Invariably obtained as amorphous solids, they are best characterized through their highly crystalline oximes. (C) 2009 Elsevier Ltd. All rights reserved.