Direct Formation of Amide-Linked C-Glycosyl Amino Acids and Peptides via Photoredox/Nickel Dual Catalysis

Journal of the American Chemical Society, Год журнала: 2024, Номер 146(8), С. 5502 - 5510

Опубликована: Фев. 15, 2024

Glycoproteins account for numerous biological processes including those associated with diseases and infections. The advancement of glycopeptides has emerged as a promising strategy unraveling pathways discovering novel medicines. In this arena, key challenge arises from the absence efficient synthetic strategies to access glycoproteins. Here, we present highly concise approach bridging saccharides amino acids peptides through an amide linkage. Our amide-linked C-glycosyl are synthesized cooperative Ni-catalyzed photoredox processes. catalytic process generates glycosyl radical carbonyl radical, which subsequently combine yield products. saccharide reaction partners encompass mono-, di-, trisaccharides. All 20 natural acids, peptides, their derivatives can efficiently undergo glycosylations yields ranging acceptable high, demonstrating excellent stereoselectivities. As substantial expansion applications, have shown that simple function versatile building units constructing C-glycopeptides intricate spatial complexities.

Язык: Английский

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Catalytic Glycosylation for Minimally Protected Donors and Acceptors

Nature, Год журнала: 2024, Номер 632(8024), С. 313 - 319

Опубликована: Июнь 17, 2024

Язык: Английский

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Direct Synthesis of Unprotected C-Glycosides via Photoredox Activation of Glycosyl Ester

Organic Letters, Год журнала: 2025, Номер unknown

Опубликована: Янв. 2, 2025

Synthetic C-glycosides play a crucial role in molecular biology and medicine. With the surge of interest demand to provide efforts with sufficient feedstock, it is highly significant pursue novel methodologies access concise efficient manner. Here, we disclose an attractive strategy that diverges itself from conventional multistep reaction sequences involving manipulations protecting groups. Widely available native sugars first react 1,4-dihydropyridine acids via site-selective Mitsunobu reaction, converting them into bench-stable radical precursors. Under visible-light-enabled photoredox catalysis conditions, resulting glycosyl radicals undergo C–C bond formation reactions, yielding variety excellent stereoselectivity. Our method demonstrates good tolerance wide range functional groups has been successfully applied post-transformation drug molecules preparation C-glycosyl amino acids.

Язык: Английский

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Total Synthesis of Nona-decasaccharide Motif from Ganoderma sinense Polysaccharide Enabled by Modular and One-Pot Stereoselective Glycosylation Strategy

Journal of the American Chemical Society, Год журнала: 2024, Номер 146(25), С. 17446 - 17455

Опубликована: Июнь 11, 2024

Polysaccharides from a medicinal fungus Ganoderma sinense represent important and adjunctive therapeutic agents for treating various diseases, including leucopenia hematopoietic injury. However, the synthetic accessibility to long, branched, complicated carbohydrates chains polysaccharides remains challenging task in chemical synthesis. Here, we report modular synthesis of nona-decasaccharide motif polysaccharide GSPB70-S with diverse biological activities first time through one-pot stereoselective glycosylation strategy on basis glycosyl ortho-(1-phenyvinyl)benzoates, which not only sped up but also reduced waste avoided aglycones transfer issues inherent thioglycosides. The route highlights following key steps: (1) preactivation-based highly constructions several 1,2-cis-glycosidic linkages, three α-d-GlcN-(1 → 4) linkages one α-d-Gal-(1 bond via reagent N-methyl-N-phenylformamide modulation; (2) orthogonal assembly 1,2-trans-glycosidic linear branched glycans fragments by strategic combinations N-phenyltrifluoroacetimidates, ortho-alkynylbenzoates, ortho-(1-phenyvinyl)benzoates; (3) final [1 × 4 + 15] Yu efficient target. Additionally, shorter sequences 4-mer, 5-mer, 6-mer are prepared structure–activity relationship studies. present work shows that this can offer reliable effective means streamline complex many bonds.

Язык: Английский

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Unveiling Heavier Dihydropyridine Chalcogenol Esters in Metallaphotoredox Catalyst-Enabled Regioselective Hydrothio(seleno)carbonylation

Organic Letters, Год журнала: 2025, Номер unknown

Опубликована: Янв. 23, 2025

Herein, aromaticity-driven thio(seleno)ester group transfer from novel 1,4-dihydropyridine thio(seleno)esters to alkene feedstocks is disclosed by merging palladium and photoredox catalysis. In this process, photoactivation of dihydropyridine integrated with regioselective hydrometalation alkenes, avoiding photoinduced Pd-C bond homolysis organopalladium intermediates. Additionally, a hydroselenocarbonylation an accomplished for the first time using bench-stable selenoester reagent. The activation mode thioesters has been illustrated detailed mechanistic studies, spectroscopic analysis, intermediate trapping, isotope labeling experiments.

Язык: Английский

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Iridium Photoredox-Catalyzed Stereoselective C-Glycosylation with Tetrafluoropyridin-4-yl Thioglycosides: A Facile Synthesis of C-α/β-Glucogallins and Their Antioxidant Activity

ACS Catalysis, Год журнала: 2024, Номер unknown, С. 17727 - 17738

Опубликована: Ноя. 18, 2024

We demonstrate an efficient, scalable, and stereoselective C-glycosylation with thioglycosides possessing a unique photoactive tetrafluoropyridin-4-yl (TFPy) thio radical leaving group, affording editable medicinally biologically essential C-α-glucogallin derivatives. In the presence of silyl enol ether acceptors, desulfurative coupling reaction performs smoothly under mild conditions upon exposure to blue light irradiation. This versatile protocol permits synthesis sugar-drug chimeras by C1 ketonylation complex drug-derived ethers. The scale-up synthesis, anomeric epimerization, post-C-glycosylation modification ketone sugars showcase reaction's potential utilities. Furthermore, could be applied direct carbohydrate skeleton editing equipping group on nonanomeric position. is viable for unprotected TFPy thioglycoside, route ketonyl sugars. concise six-step assembly both configurated C-glucogallins from commercially cheap glucose pentaacetate their antioxidant reactivity investigations underline promising medicinal relevance our current protocols. mechanism was investigated through trapping experiment, oxocarbenium fluorescence quenching Stern–Volmer analysis, confirming that major glycosyl intermediates are generated thioglycoside donors, whose effectively quench excited Ir(ppy)3 oxidative process, complementary product, accounting examples moderate selectivities.

Язык: Английский

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Recent Advances in NHC‐Catalyzed Chemoselective Activation of Carbonyl Compounds

Chemistry - An Asian Journal, Год журнала: 2024, Номер 19(9)

Опубликована: Март 7, 2024

N-Heterocyclic carbenes (NHCs) catalysts have been employed as effective tools in the development of various reactions, which made notable contributions developing diverse reaction modes and generating significant functionalized molecules. This review provides an overview recent advancements chemo- regioselective activation different aldehydes using NHCs, categorized into five parts based on modes. A brief conclusion outlook is provided to stimulate novel for accessing functional

Язык: Английский

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Emerging Advances of the Radical Pathway Glycosylation Enabled by Bench‐Stable Glycosyl Donors: Glycosyl Sulfoxides, Glycosyl Sulfones, and Glycosyl Sulfinates

Advanced Synthesis & Catalysis, Год журнала: 2024, Номер 366(19), С. 4017 - 4041

Опубликована: Июль 30, 2024

Abstract In synthetic carbohydrate chemistry, the modification of glycosyl radicals pathway stands as a central area focus. The radical‐based reactions often demonstrate remarkable compatibility with various functional groups owing to mild initiation conditions. particular, identification novel radical precursors, combined advanced reaction techniques, has substantially broadened scope compound synthesis. Despite presence versatile donors, synthesis noble donors is still addressed need and challenges associated sugar chemistry. Currently, new class precursors been developed which enables production C ‐, S O N ‐glycosides efficiently. this light, we highlight strategies towards bench‐stable sulfoxides, sulphone, sulfite that can enable site‐, regio‐ stereoselective transformation protected or naked synthons in Here, review article covers recent developments selective diversification such alkylation, arylation, alkenylation, sulfuration, C−H activation, DNA conjugation via along mechanistic aspects, challenges, future directions.

Язык: Английский

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Stereoselective Construction of Multifunctional C-Glycosides Enabled by Nickel-Catalyzed Tandem Borylation/Glycosylation

Journal of the American Chemical Society, Год журнала: 2024, Номер 146(32), С. 22413 - 22423

Опубликована: Авг. 3, 2024

Stereochemically pure saccharides have indispensable roles in fields ranging from medicinal chemistry to materials science and organic synthesis. However, the development of a simple, stereoselective, efficient glycosylation protocol access α- β-C-glycosides (particularly 2-deoxy entities) remains persistent challenge. Existing studies primarily focused on C1 modification carbohydrates transformation glycosyl radical precursors. Here, we innovate by harnessing situ generated glycosyl-Ni species achieve one-pot borylation cascade manner, which is enabled an earth-abundant nickel-catalyzed carboboration readily accessible glycals without any ligand. This work reveals potential for modular multifunctional platform facilitate simultaneous introduction C-C C-B bonds at stereogenic center saccharides, largely unexploited research area. Preliminary experimental computational indicate that endocyclic O C3 group play important stereoseclectively forging glycosidic bonds. As result, diverse range C-R (R = alkyl, aryl, alkenyl) 2-deoxygenated glycosides bearing modifiable boron groups could be rapidly made with excellent stereocontrol exhibit remarkable functional tolerance. The synthetic underscored late-stage natural products commercial drugs as well facile preparation various rare sugars, bioactive conjugates, key intermediates prorocentin, phomonol, aspergillide A.

Язык: Английский

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Regiodivergent Functionalization of Protected and Unprotected Carbohydrates using Photoactive 4‐Tetrafluoropyridinylthio Fragment as an Adaptive Activating Group

Angewandte Chemie International Edition, Год журнала: 2024, Номер 63(52)

Опубликована: Авг. 29, 2024

Abstract The selective functionalization of carbohydrates holds a central position in synthetic carbohydrate chemistry, driving the ongoing quest for ideal approaches to manipulate these compounds. In this study, we introduce general strategy that enables regiodivergent saccharides. use electron‐deficient photoactive 4‐tetrafluoropyridinylthio (SPyf) fragment as an adaptable activating group, facilitated efficient across all saccharide sites. More importantly, group can be directly installed at C1, C5 and C6 positions biomass‐derived single step site‐selective manner, allowing precision‐oriented modification unprotected saccharides glycans.

Язык: Английский

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