Advances on Synthesis of Flavonoid Glycosides

Abstract

Flavonoid glycoside is commonly found in natural plants, possesses diverse bioactivities and potential medicinal values, and its synthesis methods are worthy to be studied. The synthesis of flavonoid glycosides covering the literatures from 2014 to 2018 is reviewed. The flavonoid glycoside synthesis includes two major methods of chemosynthesis and biosynthesis. Chemosynthesis includes total synthesis and semi-synthesis. The total synthesis has two classical methods of the Baker-Venkataraman (BK-VK) reaction and the Algar-Flynn-Oyamada (AFO) reaction. The semi-synthesis is usually starting from natural flavonoid, such as rutin, quercetin, kaempferol, naringenin and so on. Moreover, the chemosynthesis of flavonoid O-glucoside has three prime methods, Koening-Knorr method, phase transfer catalysis method, and glycosyl trichloroacetimidate method. As for the chemosynthesis of flavonoid C-glycoside, its glycosidic linkage is mainly completed via the O→C rearrangement reaction. Currently, the glycosyltransferase and glycosynthase are usually employed in the enzyme-catalyzed biosynthesis of flavonoid glycosides.

Microbial Transformation of Galangin Derivatives and Cytotoxicity Evaluation of Their Metabolites

“…Thus, more interest has been drawn to the isolation and pharmacological study of these types of compounds. Though many well-designed chemical glycosylation methods are available, it is not easy to accomplish regioselective glycosylation since it is often hampered by the presence of various hydroxyl groups in the glycosylation acceptors (i.e., aglycones) [20,21]. It is often required that these hydroxyl groups be selectively protected and deprotected to avoid by-product formation in the glycosylation process [21,22].…”

Variations of Flavone Glycosides Profile Underscore the Necessity of Quality Control of Prepared Microctis Folium Slices

“…The ten flavone glycosides were all hydroxylated in positions 5 and 7. Furthermore, the C-glycosides have sugar substituent directly bound to 6-C and 8-C, whereas the O-glycosides have sugar substituents located at position C-3 [ 29 , 30 ]. Different structures always lead to various fragmentation pathways.…”

Crystal structure of 3-acetyl-4-hydroxybenzoic acid, C18H16O8

“…Because of their extensive biological activity and strong pharmacological action, the synthesis of flavonoids have attracted much research interest [10][11][12][13][14]. The total synthesis of flavone compounds has two classical methods of the Baker-Venkataraman reaction and the Algar-Flynn-Oyamada reaction [15,16]. We still focused on the synthesis and antibacterial activities of preservatives.…”