scholarly journals Intramolecular glycosylation

2017 ◽  
Vol 13 ◽  
pp. 2028-2048 ◽  
Author(s):  
Xiao G Jia ◽  
Alexei V Demchenko
Keyword(s):  
Review Article ◽  
Donor And Acceptor ◽  
Leaving Group ◽  
Glycosyl Donor

Carbohydrate oligomers remain challenging targets for chemists due to the requirement for elaborate protecting and leaving group manipulations, functionalization, tedious purification, and sophisticated characterization. Achieving high stereocontrol in glycosylation reactions is arguably the major hurdle that chemists experience. This review article overviews methods for intramolecular glycosylation reactions wherein the facial stereoselectivity is achieved by tethering of the glycosyl donor and acceptor counterparts.

scholarly journals Structures of cell wall arabinosyltransferases with the anti-tuberculosis drug ethambutol

Science ◽  
2020 ◽  
Vol 368 (6496) ◽  
pp. 1211-1219 ◽  
Author(s):  
Lu Zhang ◽  
Yao Zhao ◽  
Yan Gao ◽  
Lijie Wu ◽  
Ruogu Gao ◽  
...  
Keyword(s):  
Cell Wall ◽  
Active Site ◽  
Structural Basis ◽  
Drug Resistant ◽  
Cell Wall Synthesis ◽  
X Ray ◽  
Cryo Electron Microscopy ◽  
Donor And Acceptor ◽  
Biochemical Function ◽  
Glycosyl Donor

The arabinosyltransferases EmbA, EmbB, and EmbC are involved in Mycobacterium tuberculosis cell wall synthesis and are recognized as targets for the anti-tuberculosis drug ethambutol. In this study, we determined cryo–electron microscopy and x-ray crystal structures of mycobacterial EmbA-EmbB and EmbC-EmbC complexes in the presence of their glycosyl donor and acceptor substrates and with ethambutol. These structures show how the donor and acceptor substrates bind in the active site and how ethambutol inhibits arabinosyltransferases by binding to the same site as both substrates in EmbB and EmbC. Most drug-resistant mutations are located near the ethambutol binding site. Collectively, our work provides a structural basis for understanding the biochemical function and inhibition of arabinosyltransferases and the development of new anti-tuberculosis agents.

Chemo-enzymatic synthesis of Lacto-N-biose I catalyzed by β-1,3 galactosidase from Bacillus circulans using 4,6-dimethoxy-1,3,5-triazin-2-yl β-galactopyranoside as a glycosyl donor

2021 ◽  
Author(s):  
Takayuki Ohnuma ◽  
Tomoki Taku ◽  
Takeshi Nagatani ◽  
Atsushi Horii ◽  
Shun Imaoka ◽  
...  
Keyword(s):  
Enzymatic Synthesis ◽  
Maximum Yield ◽  
Bacillus Circulans ◽  
Donor Substrate ◽  
Donor And Acceptor ◽  
Glycosyl Donor ◽  
Substrate Ratio

Abstract Chemo-enzymatic synthesis of lacto-N-biose I (LNB) catalyzed by β-1,3 galactosidase from Bacillus circulans (BgaC) has been developed using 4,6-dimethoxy-1,3,5-triazin-2-yl β-galactopyranoside [DMT-β-Gal] and GlcNAc as the donor and acceptor substrates, respectively. BgaC transferred the Gal moiety to the acceptor, giving rise to LNB. The maximum yield of LNB was obtained at the acceptor: donor substrate ratio of 1:30.

Synthesis of a New Type ofd-Mannosamine Glycosyl Donor and Acceptor and their Use for the Preparation of Oligosaccharides Consisting ofd-Mannosamine Units Linked by α(1→4)-Glycosidic Bonds

Synthesis ◽  
2008 ◽  
Vol 2008 (16) ◽  
pp. 2610-2616 ◽  
Author(s):  
Miroslav Ledvina ◽  
Matyáš Turský ◽  
Jan Veselý ◽  
Iva Tišlerová ◽  
Tomáš Trnka
Keyword(s):  
Glycosidic Bonds ◽  
Donor And Acceptor ◽  
New Type ◽  
Glycosyl Donor

scholarly journals Copper-Catalyzed Insertion of Diazo Compounds into Vinyl Hypervalent Iodine Reagents to Generate Allylic Esters

2019 ◽  
Author(s):  
Guillaume Pisella ◽  
Alec Gagnebin ◽  
Jerome Waser
Keyword(s):  
Functional Groups ◽  
Allylic Alcohol ◽  
Diazo Compounds ◽  
Hypervalent Iodine ◽  
Aryl Iodide ◽  
Broad Scope ◽  
Donor And Acceptor ◽  
Leaving Group ◽  
Donor Acceptor ◽  
Allylic Esters

An unprecedented copper(I)-catalyzed vinylation of (donor)-acceptor diazo compounds with VinylBenziodoXolone reagents (VBX) as partners is reported. The transformation tolerates variation of both donor- and acceptor substituents on the diazo compounds, delivering the corresponding benzoylated allylic alcohol products in good to excellent yields. Through the development of a protocol for the synthesis of functionalized alkanes-, dienes- and enynes-substituted VBX reagents, a broad scope of substituents on the alkene could be accessed. The obtained products contain synthetically versatile functional groups, such as an aryl iodide, an ester and an allylic leaving group, enabling selective further modification.

scholarly journals Copper-Catalyzed Insertion of Diazo Compounds into Vinyl Hypervalent Iodine Reagents to Generate Allylic Esters

2019 ◽  
Author(s):  
Guillaume Pisella ◽  
Alec Gagnebin ◽  
Jerome Waser
Keyword(s):  
Functional Groups ◽  
Allylic Alcohol ◽  
Diazo Compounds ◽  
Hypervalent Iodine ◽  
Aryl Iodide ◽  
Broad Scope ◽  
Donor And Acceptor ◽  
Leaving Group ◽  
Donor Acceptor ◽  
Allylic Esters

An unprecedented copper(I)-catalyzed vinylation of (donor)-acceptor diazo compounds with VinylBenziodoXolone reagents (VBX) as partners is reported. The transformation tolerates variation of both donor- and acceptor substituents on the diazo compounds, delivering the corresponding benzoylated allylic alcohol products in good to excellent yields. Through the development of a protocol for the synthesis of functionalized alkanes-, dienes- and enynes-substituted VBX reagents, a broad scope of substituents on the alkene could be accessed. The obtained products contain synthetically versatile functional groups, such as an aryl iodide, an ester and an allylic leaving group, enabling selective further modification.

scholarly journals Regioselective Silyl/Acetate Exchange of Disaccharides Yields Advanced Glycosyl Donor and Acceptor Precursors

2013 ◽  
Vol 78 (19) ◽  
pp. 9677-9688 ◽  
Author(s):  
Hsiao-Wu Hsieh ◽  
Matthew W. Schombs ◽  
Mark A. Witschi ◽  
Jacquelyn Gervay-Hague
Keyword(s):  
Donor And Acceptor ◽  
Glycosyl Donor
Sign in / Sign up

Export Citation Format

Share Document