Deoxy sugars. General methods for carbohydrate deoxygenation and glycosidation

Abstract

Deoxy sugars represent an important class of carbohydrates, present in a large number of biomolecules involved in multiple biological processes. In various antibiotics, antimicrobials, and therapeutic agents the presence of...

Decarboxylation in Natural Products Biosynthesis

“…Deoxygenated carbohydrate moieties, prevalent in antibiotics, antimicrobials, and therapeutic agents, play a crucial role in imparting biological functionality and enhancing receptor affinity. , Pyranose deoxypentoses, deoxy sugars found in various natural products (Figure ), are predominantly synthesized through glucuronic acid decarboxylases, members of the short-chain dehydrogenase/reductase (SDR) enzyme family. − As shown in Figure , an example deoxypentose biosynthesis involves (1) activation of α-D-glucose-1-phosphate by α-D-glucose-1-phosphate nucleotidyltransferase (EvdS4) to give NDP-α-D-glucose, (2) oxidation of NDP-α-D-glucose by NDP-α-D-glucosedehydrogenase (EvdS1) to give NDP-α- D-glucuronic acid, (3) C-4 oxidation of NDP-α-D-glucuronic acid using NAD + by glucuronic acid decarboxylase (EvdS6), facilitating C-6 decarboxylation. The intermediate formed after the decarboxylation can be either 4-keto-pentose or 4-hydroxy-pentose.…”

Transition-Metal-Free β-Selective C-Glycosylation of β-Glycosyl Boronates via Stereoretentive 1,2-Migration

“…4 The corresponding C-glycoside analogues, in which a cleavable O-glycoside linkage is replaced by a C-glycoside, are expected to retain similar biological activities in cells and are considered to be useful molecular tools to elucidate the functions of glycans. [5][6][7] Among the glycans, 2-deoxy sugars exhibit unique biological activities; 8 consequently, the corresponding 2-deoxy-C-glycosides should be valuable for chemical-biology studies. 9 Because the configuration of the anomeric center is critical for biological activity, stereocontrolled syntheses of both -and -C-glycosides are required.…”

All-in-One Synthesis of 3,6-Dideoxysugars: An Olefin Metathesis–Isomerization Approach

“…Moreover, 3,6-deoxysugars are adapted as fascinating surrogates for understanding the enzyme–substrate interaction in the biosynthesis of glycoconjugates as well as in metabolism . Therefore, the decoration of deoxysugars in total synthesis and structural derivatization is intriguing because of their structural uniqueness and biological significance. , …”

“…3,6-Deoxysugars are present in the lipopolysaccharide (LPS) of some Gram-negative bacteria and act as the immunodominant monosaccharides and the terminal nonreducing units in the O-antigens . Moreover, 3,6-deoxysugars are adapted as fascinating surrogates for understanding the enzyme–substrate interaction in the biosynthesis of glycoconjugates as well as in metabolism . Therefore, the decoration of deoxysugars in total synthesis and structural derivatization is intriguing because of their structural uniqueness and biological significance. , …”