No abstract

Amadori and Heyns reactions are milestone reactions of carbohydrate chemistry. There have been little efforts in transforming these rearrangement reactions to useful catalytic tools. We demonstrate herein, synthesis of Amadori and Heyns dipeptides via Lewis acid-catalysis. The accomplished catalytic Amadori and Heyns synthesis is devoid of protection and deprotection steps either for dipeptides or for reducing sugar. By the developed catalytic method we achieved, tagatose Amadori dipeptides via reaction of D-galactose with dipeptides including L-alanyl glycine, L-alanyl-L-alanine, L-alanyl-L-glutamine, glycyl-L-phenylalanine, L-leucyl glycine, L-pheynylalanyl-L-valine in excellent yield. In addition, Heyns dipeptides were also achieved by employing D-fructose and dipeptides consisting of L-alanyl glycine, L-alanyl-L-alanine, L-alanyl-L-glutamine, glycyl-L-phenylalanine, L-leucyl glycine. The realized Lewis acid mediated catalytic method is practical, quantitative, and avoids chromatographic separation techniques.

No abstract