Catalytic Glycosylation for Minimally Protected Donors and Acceptors

Nature, Journal Year: 2024, Volume and Issue: 632(8024), P. 313 - 319

Published: June 17, 2024

Language: Английский

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Carbene-catalyzed chirality-controlled site-selective acylation of saccharides

Nature Communications, Journal Year: 2025, Volume and Issue: 16(1)

Published: Jan. 2, 2025

Acylation stands as a fundamental process in both biological pathways and synthetic chemical reactions, with acylated saccharides their derivatives holding diverse applications ranging from bioactive agents to building blocks. A longstanding objective organic synthesis has been the site-selective acylation of without extensive pre-protection alcohol units. In this study, we demonstrate that by simply altering chirality N-heterocyclic carbene (NHC) catalysts, site-selectivity saccharide reactions can be effectively modulated. Our investigation reveals intriguing selectivity shift stems combination factors, including match/mismatch inter- / intramolecular hydrogen bonding between NHC catalyst substrates. These findings provide valuable insights into design reaction engineering, highlighting potential glycoside analysis, such fluorescent labelling, α/β identification, orthogonal selective late-stage modifications. The units synthesis. Here, authors

Language: Английский

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Site-Selective C–O Bond Editing of Unprotected Saccharides

Journal of the American Chemical Society, Journal Year: 2023, Volume and Issue: 146(1), P. 824 - 832

Published: Dec. 20, 2023

Glucose and its polyhydroxy saccharide analogs are complex molecules that serve as essential structural components in biomacromolecules, natural products, medicines, agrochemicals. Within the expansive realm of saccharides, a significant area research revolves around chemically transforming naturally abundant units to intricate or uncommon such oligosaccharides rare sugars. However, partly due presence multiple hydroxyl groups with similar reactivities complexities arising from stereochemistry, transformation unprotected sugars desired target remains challenging. One formidable challenge lies efficient selective activation modification C–O bonds saccharides. In this study, we disclose modular 2-fold "tagging–editing" strategy allows for direct editing enabling rapid preparation valuable drug derivatives. The first step, referred "tagging", involves catalytic site-selective installation photoredox active carboxylic ester group specific unit an sugar. second namely, "editing", features bond cleavage form carbon radical intermediate undergoes further transformations C–H C–C formations. Our constitutes most effective shortest route medicines other bearing

Language: Английский

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Synergistic catalysis: An emerging concept for selective carbohydrate synthesis

Chem Catalysis, Journal Year: 2024, Volume and Issue: 4(3), P. 100891 - 100891

Published: Jan. 18, 2024

Harnessing modern catalytic concepts to address long-standing challenges in carbohydrate chemistry has garnered substantial interest from the synthetic community recent years. In particular, usage of multiple catalysts for sequential one-pot relay reactions already contributed major benefits accessing oligosaccharides past two decades. contrast, exploitation synergistic catalysis glycosciences is only its infancy. While methods combine stepwise into a single flask operation, they do not intrinsically alter reaction mechanisms. Conversely, involves creation unique mechanistic pathways by merging cycles. At nexus cycles, fertile opportunities arise bond-forming strategies that are possible within individual manifold. The realization underexploited potential expected accelerate developments field, thereby offering stereoselective entry points glycosidic chemical space was previously inaccessible.

Language: Английский

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

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

Published: Jan. 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.

Language: Английский

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Growing Impact of Intramolecular Click Chemistry in Organic Synthesis

The Chemical Record, Journal Year: 2023, Volume and Issue: 23(11)

Published: July 31, 2023

Abstract Click Chemistry, a modular, rapid, and one of the most reliable tool for regioselective 1,2,3‐triazole forming [3+2] reaction organic azide terimal alkyne is widely explored in various emerging domains research ranging from chemical biology to catalysis medicinal chemistry material science. This diverse range azido‐alkyne scaffolds has been well performed both intermolecular as intramolecular fashions. In comparison metal (Cu/Ru/Ni) variant ‘Click Chemistry’, click little addressed. The exemplified mordern cyclization which involves metal‐catalyzed (CuAAC/RuAAC) cyclization, organo‐catalyzed thermal‐induced topochemical reaction. Thus, we report herein recent approaches on azide‐alkyne cycloaddition Chemistry‘ with their wide‐spread applications developement molecules including fused‐heterocycles, well‐defined peptidomemics, macrocyclic architectures notable features.

Language: Английский

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Recent Advances in NHC‐Catalyzed Chemoselective Activation of Carbonyl Compounds

Chemistry - An Asian Journal, Journal Year: 2024, Volume and Issue: 19(9)

Published: March 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

Language: 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, Journal Year: 2024, Volume and Issue: 63(52)

Published: Aug. 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.

Language: Английский

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Asymmetric Pd/Organoboron‐Catalyzed Site‐Selective Carbohydrate Functionalization with Alkoxyallenes Involving Noncovalent Stereocontrol

Angewandte Chemie International Edition, Journal Year: 2024, Volume and Issue: 63(21)

Published: March 26, 2024

Abstract Herein, we demonstrate the robustness of a synergistic chiral Pd/organoboron system in tackling challenging suite site‐, regio‐, enantio‐ and diastereoselectivity issues across considerable palette biologically relevant carbohydrate polyols, when prochiral alkoxyallenes were employed as electrophiles. In view burgeoning role noncovalent interactions (NCIs) stereoselective synthesis, our mechanistic experiments DFT modeling reaction path unexpectedly revealed that NCIs such hydrogen bonding CH‐π between resting states Pd‐π‐allyl complex borinate saccharide are critically involved stereoselectivity control. Our strategy thus illuminates untapped potential harnessing context transition metal catalysis to tackle challenges functionalization.

Language: Английский

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Zinc tetrafluoroborate Catalyzed Stereo‐ and Regioselective O‐Glycosylation for the Direct Synthesis of β‐Glycosides from Armed O‑Glycosyl Trichloroacetimidates

Chemistry - An Asian Journal, Journal Year: 2024, Volume and Issue: 19(15)

Published: May 27, 2024

Efficient stereo- and regioselective O-glycosylation methods remain essential to capacitate the studies of sugars sugar derivatives in various disciplines. In this work, we demonstrated an operationally simple cost-effective strategy for synthesis 1,2-trans glycosides by activation armed O-glycosyl trichloroacetimidates donor using zinc tetrafluoroborate. This mild, transition metal-free, scalable approach allowed β-glycosides with a wide range acceptors containing protecting groups/functionalities. method is exemplified synthesizing branched trisaccharide fragment related cell wall O-polysaccharide E. Coli O27.

Language: Английский

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