Synthesis of Conformationally Constrained C-Glycosyl α- and β-Amino Acids and Sugar−Carbamino Sugar Hybrids via Diels−Alder Reaction

Sugar-derived dienes undergo Diels−Alder reactions with methyl α-nitro acrylate and ethyl β-nitro acrylate to form the corresponding cycloadducts which have been converted into conformationally constrained C-glycosyl α- and β-amino acids. Further, these β-amino acids are converted into sugar−carbamino sugar hybrid molecules.