Visible Light Promoted Stereoselective C(sp3)-H Glycosylation for the Synthesis of C-Glycoamino Acids and C-Glycopeptides

Glycosylative modification of peptides could improve the pharmacological properties of peptide drugs and deliver them efficiently to the target sites. Compared with O-/N-glycosides, C-glycosides exhibit more metabolic stability. We here disclose the first example of visible-light promoted and Cu-catalyzed stereoselective C-glycosylations. The mild reaction conditions are compatible with various carbohydrate substrates, including a series of mono monosaccharides and disaccharide, and is amenable to the synthesis of a wild variety of C-glycoamino acids and C-glycopeptidomimetics with good yields and excellent stereoselectivities. The dual-functional photocatalyst formed in situ via coordination of glycine derivatives and chiral phosphine Cu complex could not only catalyze the photoredox process but also control the stereoselectivity of glycosylation reaction.