Stereoselective P(III)‐Glycosylation for the Preparation of Phosphinated Sugars DOI
Xuan Zhang,

Xian‐Xiao Chen,

Zi‐Han Li

et al.

Angewandte Chemie International Edition, Journal Year: 2024, Volume and Issue: unknown

Published: Dec. 6, 2024

Abstract Most of the reported work focus on development O ‐, N C ‐ and S ‐glycosylation methods. However, no study explores P(III)‐glycosylation reaction. Herein we describe a convenient protocol to realize process. A simple β ‐phosphino ester is adopted as P(III)‐transfer reagent for this new type glycosylation via nucleophilic substitution release strategy. Diverse phosphine units are introduced anomeric center various sugars efficiently with excellent stereoselectivity. The value method showcased by prepared P(III)‐sugars novel linkers in bioactive molecule conjugation, chiral ligands metal‐catalyzed asymmetric allylic substitutions organocatalysts. Preliminary mechanistic studies corroborated designed

Language: Английский

Efficient O- and S-glycosylation with ortho-2,2-dimethoxycarbonylcyclopropylbenzyl thioglycoside donors by catalytic strain-release DOI Creative Commons
Han Ding,

Jian Lv,

Xiao-Lin Zhang

et al.

Chemical Science, Journal Year: 2024, Volume and Issue: 15(10), P. 3711 - 3720

Published: Jan. 1, 2024

An efficient glycosylation reaction utilizing a meticulously designed thioglycoside has been developed. The well-established protocol was demonstrated in the total synthesis of TD139 and one-pot assembly E. coli O33 antigen tetrasaccharide.

Language: Английский

Citations

10
Direct Synthesis of α- and β-2′-Deoxynucleosides with Stereodirecting Phosphine Oxide via Remote Participation DOI
Xintong Tang,

Yueer Zhou,

Yingjie Wang

et al.

Journal of the American Chemical Society, Journal Year: 2024, Volume and Issue: 146(12), P. 8768 - 8779

Published: March 14, 2024

2′-Deoxynucleosides and analogues play a vital role in drug development, but their preparation remains significant challenge. Previous studies have focused on β-2′-deoxynucleosides with the natural β-configuration. In fact, isomeric α-2′-deoxynucleosides also exhibit diverse bioactivities even better metabolic stability. Herein, we report that both α- can be prepared high yields stereoselectivity using remote directing diphenylphosphinoyl (DPP) group. It is particularly efficient to prepare an easily accessible 3,5-di-ODPP donor. Instead of acting as H-bond acceptor 2-(diphenylphosphinoyl)acetyl (DPPA) group our previous for syn-facial O-glycosylation, phosphine oxide moiety here acts participating enable highly antifacial N-glycosylation. This proposed participation mechanism supported by first characterization important 1,5-briged P-heterobicyclic intermediate via variable-temperature NMR spectroscopy. Interestingly, antiproliferative assays led α-2′-deoxynucleoside IC50 values low micromole range against central nervous system tumor cell lines SH-SY5Y LN229, whereas its β-anomer exhibited no inhibition at 100 μM. Furthermore, DPP significantly enhanced antitumor activities 10 times.

Language: Английский

Citations

9
Purification-Free Preparation of Trifluoroacetimidoyl Chlorides and Their Use in Catalytic Chemical Glycosylation DOI

Nikolai Cordua,

S. Steffensen,

A. Mascherpa

et al.

Organic Letters, Journal Year: 2025, Volume and Issue: unknown

Published: Feb. 11, 2025

This Letter describes a purification-free method for synthesizing 2,2,2-trifluoro-N-phenylacetimidoyl chloride and several related congeners from their corresponding amides using POCl3 pyridine. N-(2,4-Dichlorophenyl)-2,2,2-trifluoroacetimidoyl demonstrated superior stability compared to chloride, which is commonly used glycosyl donor synthesis of the Yu-type. The described also enabled general highly β-selective trifluoroacetimidate donors DABCO in toluene. were shown undergo efficient glycosylation with various acceptors.

Language: Английский

Citations

1
Recent advances in stereoselective 1,2-cis-O-glycosylations DOI Creative Commons
Akihiro Ishiwata, Katsunori Tanaka,

Jiaming Ao

et al.

Frontiers in Chemistry, Journal Year: 2022, Volume and Issue: 10

Published: Aug. 19, 2022

For the stereoselective assembly of bioactive glycans with various functions, 1,2-

Language: Английский

Citations

29
Total synthesis ofLentinus giganteusglycans with antitumor activitiesviastereoselective α-glycosylation and orthogonal one-pot glycosylation strategies DOI Creative Commons

Yunqin Zhang,

Yanlei Hu, Shanshan Liu

et al.

Chemical Science, Journal Year: 2022, Volume and Issue: 13(26), P. 7755 - 7764

Published: Jan. 1, 2022

Stereoselective and one-pot synthesis of Lentinus giganteus glycans with antitumor activities has been accomplished, which features a newly developed merging reagent modulation remote anchimeric assistance (RMRAA) α-galactosylation strategy.

Language: Английский

Citations

20
Chemical Synthesis and Antigenicity Evaluation of Shigella dysenteriae Serotype 10 O-Antigen Tetrasaccharide Containing a (S)-4,6-O-Pyruvyl Ketal DOI
Chunjun Qin, Lingxin Li, Guangzong Tian

et al.

Journal of the American Chemical Society, Journal Year: 2022, Volume and Issue: 144(46), P. 21068 - 21079

Published: Nov. 10, 2022

Shigella is the second most common etiologic pathogen responsible for childhood acute diarrhea. An anti-Shigella vaccine still eagerly awaited due to increasing drug resistance of this pathogen. The O-antigen a promising target. To identify immune epitopes glycan, first total synthesis dysenteriae serotype 10 tetrasaccharide containing (S)-4,6-O-pyruvyl ketal was completed. 1,2-trans-β-glycosylation & C2 epimerization and conformational locking strategies facilitated construction two 1,2-cis-β-glycosidic linkages. reactivities both glycosyl donor acceptor were improved by adding electron-donating benzyl groups, enabling an efficient assembly tetrasaccharide. introduced at final stage its influence on glycosylation stereospecificity efficiency. In addition, (R)-4,6-O-pyruvylated nonpyruvylated tetrasaccharides three further fragments synthesized. Glycan microarray screening revealed that repeating unit key antigenic epitope O-antigen. Moreover, essential structural feature antigen designing carbohydrate-based vaccines against S. 10. comparison (S)-4,6-O-pyruvylated glycan (R)-epimer will set example biological evaluation other bacterial glycans pyruvyl ketals.

Language: Английский

Citations

20
Palladium-Catalyzed O-Glycosylation through π–π Interactions DOI

Yangxing Sun,

Keke Ren,

Zhentao Zhang

et al.

Organic Letters, Journal Year: 2024, Volume and Issue: 26(25), P. 5396 - 5401

Published: June 13, 2024

A stereodivergent synthesis of β- and α-O-glycosides using 3-O-quinaldoyl glucals was developed by palladium catalysis at 60 110 °C respectively. Various alcohols, monosaccharides, amino acid were glycosylated to form α- products in good yields with high stereoselectivity. Mechanistic studies indicated no classic Pd–N (quinoline) coordination, but π–π stacking interactions promoted the anomeric stereodiversity. The practicality demonstrated glycosylating natural products/drugs synthesizing a complex tetrasaccharide.

Language: Английский

Citations

4
Stabilization of Glucosyl Dioxolenium Ions by “Dual Participation” of the 2,2-Dimethyl-2-(ortho-nitrophenyl)acetyl (DMNPA) Protection Group for 1,2-cis-Glucosylation DOI Creative Commons
Wouter A. Remmerswaal, Kas J. Houthuijs, Roel van de Ven

et al.

The Journal of Organic Chemistry, Journal Year: 2022, Volume and Issue: 87(14), P. 9139 - 9147

Published: June 24, 2022

The stereoselective introduction of glycosidic bonds is paramount importance to oligosaccharide synthesis. Among the various chemical strategies steer stereoselectivity, participation by either neighboring or distal acyl groups used particularly often. Recently, use 2,2-dimethyl-2-(ortho-nitrophenyl)acetyl (DMNPA) protection group was shown offer enhanced steering compared other groups. Here, we investigate origin stereoselectivity induced DMNPA through systematic glycosylation reactions and infrared ion spectroscopy (IRIS) combined with techniques such as isotopic labeling anomeric center isomer population analysis. Our study indicates that does not lie in direct nitro moiety but formation a dioxolenium strongly stabilized group.

Language: Английский

Citations

18
Isothiourea – catalyzed α-selective glycosylations DOI Creative Commons

Bhaswati Ghosh,

Charles Enlow,

Zhengyue Ma

et al.

Chemical Communications, Journal Year: 2025, Volume and Issue: unknown

Published: Jan. 1, 2025

Here, we disclose the discovery that isothioureas efficiently catalyze formation of both α-1,2- cis and trans glycosyl linkages from either bromide or chloride donors, furnishing glycosides in good to complete selectivities.

Language: Английский

Citations

0
The effect of neighbouring group participation and possible long range remote group participation in O-glycosylation DOI Creative Commons
Rituparna Das, Balaram Mukhopadhyay

Beilstein Journal of Organic Chemistry, Journal Year: 2025, Volume and Issue: 21, P. 369 - 406

Published: Feb. 17, 2025

Stereoselective glycosylations are one of the most challenging tasks synthetic glycochemists. The protecting building blocks on glycosides contribute significantly in attaining required stereochemistry resulting glycosides. Strategic installation suitable groups C-2 position, vicinal to anomeric carbon, renders neighbouring group participation, whereas distal C-3, C-4, and C-6 positions often claimed exhibit remote participation with carbon. Neighbouring being widely studied help glycochemists design protocols for multistep synthesis complex oligosaccharides turn, standardise process glycosylation towards a particular stereochemical output. While has been quite effective achieving produced glycosides, exhibits comparatively less efficacy complete stereoselectivity reactions. Remote is still highly debated topic scientific community. However, implementing participating role reactions practised achieve better stereocontrol facilitate formation synthetically glycosidic linkages.

Language: Английский

Citations

0