Organoelectrophotocatalytic Generation of Acyl Radicals from Formamides and Aldehydes: Access to Acylated 3-CF₃-2-Oxindoles

Organic Letters, Journal Year: 2023, Volume and Issue: 25(38), P. 7014 - 7019

Published: Sept. 18, 2023

Organoelectrophotocatalytic generation of acyl radicals from formamides and aldehydes to synthesize acylated 3-CF3-2-oxindoles has been developed. This protocol features a monocatalytic system using 9,10-phenanthrenequinone (PQ) both as catalyst hydrogen atom transfer (HAT) reagent, which avoids the use an external HAT metal oxidant. A variety have obtained in satisfactory yields CF3-substituted N-arylacrylamides via tandem radical cyclization.

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

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

Published: Jan. 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.

Language: Английский

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Visible‐Light‐Mediated Photocatalyst‐Free Hydroacylation of Azodicarboxylic Acid Derivatives with 4‐Acyl‐1,4‐dihydropyridines

Chinese Journal of Chemistry, Journal Year: 2024, Volume and Issue: 42(11), P. 1230 - 1236

Published: Feb. 5, 2024

Comprehensive Summary A visible‐light‐enabled, photocatalyst‐free hydroacylation reaction of azodicarboxylic acid derivatives was described. This radical conjugate addition (RCA) protocol relied on the dual role 4‐acyl‐1,4‐dihydropyridine (acyl‐DHP) reagents that besides being as reservoirs, they also enabled conversion adducts to anion intermediates via reduction. Under “catalyst‐oxidant‐additive free” conditions, a wide range structurally different acyl hydrazide products were readily obtained in 56%—99% yields. The utility this transformation further demonstrated by scale‐up synthesis and downstream derivatization.

Language: Английский

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Multifunctional Lipidated Protein Carrier with a Built-In Adjuvant as a Universal Vaccine Platform Potently Elevates Immunogenicity of Weak Antigens

Journal of Medicinal Chemistry, Journal Year: 2024, Volume and Issue: 67(8), P. 6822 - 6838

Published: April 8, 2024

Weak antigens represented by MUC1 are poorly immunogenic, which greatly constrains the development of relevant vaccines. Herein, we developed a multifunctional lipidated protein as carrier, in TLR1/2 agonist Pam3CSK4 was conjugated to N-terminus MUC1-loaded carrier BSA through pyridoxal 5′-phosphate-mediated transamination reaction. The resulting Pam3CSK4–BSA-MUC1 conjugate subsequently incorporated into liposomes, biomimics membrane structure tumor cells. results indicated that this significantly enhanced antigen uptake APCs and obviously augmented retention vaccine at injection site. Compared with BSA-MUC1 + groups, evoked 22- 11-fold increases MUC1-specific IgG titers. Importantly, elicited robust cellular immunity inhibited growth. This is first time constructed enhance immunogenicity, universal platform exhibits promise for utilization various vaccines, holding potential further clinical application.

Language: Английский

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Photoinduced carbamoylation reactions: unlocking new reactivities towards amide synthesis

Chemical Communications, Journal Year: 2022, Volume and Issue: 58(60), P. 8322 - 8339

Published: Jan. 1, 2022

In this review, we summarize the latest advances for amide moiety installation through photoinduced carbamoylation protocols.

Language: Английский

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Visible-Light-Induced Synthesis of 1,2-Dicarboxyl Compounds from Carbon Dioxide, Carbamoyl-dihydropyridine, and Styrene

Organic Letters, Journal Year: 2024, Volume and Issue: 26(4), P. 860 - 865

Published: Jan. 22, 2024

β-Amidated carboxylic acids, or succinamic acid derivatives, constitute a valuable chemical scaffold with broad applications in pharmaceuticals, agrochemicals, and polymer sciences. Herein, we report redox-neutral multicomponent reaction for the synthesis of derivatives good yields. This protocol involves styrene, CO2 1,4-carbamoyl-dihydropyridine as radical precursors. The method exhibits substrate scope under mild conditions, including late-stage functionalization. Moreover, by employing 13CO2, enables labeled 1,2-dicarboxylic compounds.

Language: Английский

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Minisci‐Type Carbamoylation of Azauracils with Oxamic Acids

European Journal of Organic Chemistry, Journal Year: 2024, Volume and Issue: 27(7)

Published: Jan. 19, 2024

Abstract A Minisci‐type carbamoylation of azauracils was developed to afford 6‐carbamoyl in yields up 94 %. In this transformation, oxamic acids were employed as the carbamoyl radical sources under metal‐free conditions. It features high atom economy, good functional group compatibility and convenient operation.

Language: Английский

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The Interaction Mechanism of Picolinamide Fungicide Targeting on the Cytochrome bc₁ Complex and Its Structural Modification

Journal of Agricultural and Food Chemistry, Journal Year: 2024, Volume and Issue: 72(7), P. 3755 - 3762

Published: Feb. 12, 2024

Picolinamide fungicides, structurally related to UK-2A and antimycin-A, bind into the Qi-site in bc1 complex. However, detailed binding mode of picolinamide fungicides remains unknown. In present study, antimycin-A were selected study inhibitors with four protonation states by integrating molecular dynamics simulation, docking, mechanics Generalized Born surface area (MM/GBSA) calculations. Subsequently, a series new derivatives designed synthesized further understand effects substituents on tail phenyl ring. The computational results indicated that substituted aromatic rings pharmacophore fragments made primary contribution when bound protein. Compound 9g-hydrolysis formed H-bonds Hie201 Ash228 showed an IC50 value 6.05 ± 0.24 μM against porcine 9c, simpler chemical structure, higher control than florylpicoxamid cucumber downy mildew expanded fungicidal spectrum fungicides. structural mechanistic insights obtained from will provide valuable clue for future designing promising inhibitors.

Language: Английский

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Organocatalyzed Photoelectrochemistry for the Generation of Acyl and Phosphoryl Radicals through Hydrogen Atom-Transfer Process

The Journal of Organic Chemistry, Journal Year: 2024, Volume and Issue: 89(11), P. 7531 - 7540

Published: May 18, 2024

An organocatalyzed photoelectrochemical method for the generation of acyl and phosphoryl radicals from formamides, aldehydes, phosphine oxides has been developed. This protocol utilizes 9,10-phenanthrenequinone (PQ) as both a molecular catalyst hydrogen atom-transfer (HAT) reagent, eliminating requirement external metal-based reagents, HAT oxidants. The generated can be applied to range radical-mediated transformation reactions, including C–H carbamoylation heteroarenes, intermolecular tandem radical cyclization CF3-substituted N-arylacrylamides, well intramolecular reactions. use in these transformations offers an efficient sustainable approach accessing structurally diverse carbonyl compounds.

Language: Английский

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