Abstract

Glycals are 1,2-unsaturated sugars having a C=C bond between C-1 and C-2 of the pyranose or furanose moieties of the carbohydrate scaffold. The presence of a C=C bond leads to enhanced reactivity. They are used as chiral building blocks in the synthesis of various natural products and medicinally significant molecules. There are numerous methods for the synthesis of exo-glycals and endo-glycals, such as glycosidations, reagent-based methods, and electrochemical methods. Glycals have shown their versatility and applicability in chemical synthesis in many ways e.g., epoxidation, cycloaddition, and formation of various glycosides like C-glycosides, Oglycosides, N-glycosides. They have also been employed in the synthesis of many biologically relevant natural products as starting materials.