Abstract
This chapter deals with the epimerization reactions of carbohydrate derivatives. Investigation of the principal properties of saccharides has shown that in the presence of bases, four types of transformation should be considered—anomerization, aldose–ketose isomerization, reversible aldol reaction, and β-elimination or benzylic acid rearrangement after the aldol reaction. The 1-4 isomerization and related reactions of aldoses depend strongly on the pH; anomerization and isomerization proceed under very slightly alkaline conditions, whereas the aldol reaction and benzylic acid rearrangement require a much stronger alkaline milieu. The alkaline epimerization of a mixture of the two epimeric aldoses and the respective ketoses never reaches the same equilibrium state, even after treatment for a longer time. Epimerization of uronic acids in a warm solution proceeds even at pH 7, and more easily than that of the corresponding aldoses.
Sign-in/Register to access full text options 
Free) 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a call
