Diversification of Glycosyl Compounds via Glycosyl Radicals

Angewandte Chemie International Edition, Год журнала: 2023, Номер 62(38)

Опубликована: Июнь 7, 2023

Glycosyl radical functionalization is one of the central topics in synthetic carbohydrate chemistry. Recent advances metal-catalyzed cross-coupling chemistry and metallaphotoredox catalysis provided powerful platforms for glycosyl diversification. In particular, discovery new precursors conjunction with these advanced reaction technologies have significantly expanded space compound synthesis. this Review, we highlight most recent progress area starting from 2021, reports included will be categorized based on different types better clarity.

Язык: Английский

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Radical Pathway Glycosylation Empowered by Bench-Stable Glycosyl Donors

Accounts of Chemical Research, Год журнала: 2023, Номер 56(18), С. 2473 - 2488

Опубликована: Авг. 18, 2023

ConspectusThe study of carbohydrates has emerged as a crucial research area in various disciplines due to their pivotal roles cellular processes. To facilitate in-depth exploration biological functions, chemical glycosylation reactions that allow facile access glycoconjugates broad community are highly needed. In classical reactions, glycosyl donor is activated by an acid generate reactive electrophilic intermediate, which subsequently forms glycosidic bond upon reaction with nucleophilic acceptor. Such ionic pathway been the mainstay technique for glycoconjugate synthesis and allowed numerous intricate structures. Nevertheless, limitations still exist. For instance, when labile donors or harsh activating conditions required, these methods show limited tolerance hydroxyl groups abundant on sugar rings. addition, achieving good stereocontrol represents another longstanding obstacle. recent years, new modes activation have sought tackle above challenges.We noted passing through intermediacy radicals via cascade single-electron transfer steps possess significant but underexplored potential. Progress this slow large part dearth handy maneuver radicals. Most existing call either forcing unstable/inconvenient starting materials. order better exploit power radical glycosylation, we developed range donors─namely, sulfoxides, sulfones, sulfinates─that bench stable can be readily prepared from simple These form under mild conditions. Enabled use donors, series could used making O-, S-, C-glycosides, some were previously difficult access. many cases, no protecting group required. As illustration potential utility, our adopted preparation sugar–drug conjugates, sugar–DNA glycopeptides, even glycoproteins. While most cases intrinsic reactivity intermediates explored axially configured products, also utilization external, delicate reagents, catalysts override such innate preference achieve catalyst-controlled stereoselectivity.We believe enormous inspire development novel glycoside synthesis. Account, highlight design principles summarize advancements enabled use, provide outlook future directions field.

Язык: Английский

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Transformations of carbohydrate derivatives enabled by photocatalysis and visible light photochemistry

Chemical Science, Год журнала: 2024, Номер 15(4), С. 1204 - 1236

Опубликована: Янв. 1, 2024

This review article highlights the diverse ways in which recent developments areas of photocatalysis and visible light photochemistry are impacting synthetic carbohydrate chemistry.

Язык: Английский

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N-glycoside synthesis through combined copper- and photoredox-catalysed N-glycosylation of N-nucleophiles

Nature Synthesis, Год журнала: 2024, Номер 3(5), С. 623 - 632

Опубликована: Март 1, 2024

Язык: Английский

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C–H functionalization of pyridines

Organic & Biomolecular Chemistry, Год журнала: 2023, Номер 21(28), С. 5671 - 5690

Опубликована: Янв. 1, 2023

This review discusses known approaches for selective pyridine C–H editing, focusing on recent discoveries uniquely suited to pyridines.

Язык: Английский

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Photoredox-catalyzed protecting-group-free C-glycosylation with glycosyl sulfinate via the Giese reaction

Chemical Communications, Год журнала: 2023, Номер 59(55), С. 8564 - 8567

Опубликована: Янв. 1, 2023

C-Glycoside analogs of naturally occurring glycoconjugates are useful tools for chemical biology studies, but their synthesis usually requires protection the hydroxyl groups glycosyl donors. Here we report protecting-group-free and photoredox-catalyzed C-glycosylation with sulfinates Michael acceptors via Giese radical addition.

Язык: Английский

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Carbohydrate–DNA Conjugation Enabled by Glycosyl Radicals Generated from Glycosyl Sulfinates

Organic Letters, Год журнала: 2023, Номер 26(14), С. 2686 - 2690

Опубликована: Апрель 26, 2023

Herein, we report a method that enables the synthesis of carbohydrate–DNA conjugates by radical addition. Key to success is use readily available, bench-stable, and unprotected glycosyl sulfinates as precursors radicals. The redox neutral reaction proceeds under mild simple conditions tolerates broad substrate scope. A small library was prepared.

Язык: Английский

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Visible-Light-Mediated Synthesis of C-Alkyl Glycosides via Glycosyl Radical Addition and Aryl Migration

Organic Letters, Год журнала: 2023, Номер 25(33), С. 6099 - 6104

Опубликована: Авг. 14, 2023

A visible-light-induced glycoarylation of activated olefins has been accomplished. Glycosyl radicals are generated via radical transfer strategies between (TMS)3SiOH and glycosyl bromides. Subsequent translocation rapid 1,4-aryl migration form β-sugar amide derivatives, eight types sugars compatible with this reaction. Further, the cascade reaction produced a quaternary carbon center good functional group adaptability high regioselectivity in mild conditions.

Язык: Английский

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Electrochemical Glycosylation via Halogen-Atom-Transfer for C-Glycoside Assembly

ACS Catalysis, Год журнала: 2024, Номер 14(15), С. 11532 - 11544

Опубликована: Июль 19, 2024

Glycosyl donor activation emerged as an enabling technology for anomeric functionalization, but aimed primarily at O-glycosylation. In contrast, we herein disclose mechanistically distinct electrochemical glycosyl bromide activations via halogen-atom transfer and C-glycosylation. The radical addition to alkenes led C-alkyl glycoside synthesis under precious metal-free reaction conditions from readily available bromides. robustness of our e-XAT strategy was further mirrored by C-aryl C-acyl glycosides assembly through nickela-electrocatalysis. Our approach provides orthogonal with expedient scope, hence representing a general method direct C-glycosides assembly.

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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