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Luo Y, Zhan G, Cong X, Zhang H. Editorial: Photocatalytic functionalization of inert or unsaturated bonds. Front Chem 2024; 12:1372572. [PMID: 38384728 PMCID: PMC10879561 DOI: 10.3389/fchem.2024.1372572] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/18/2024] [Accepted: 01/25/2024] [Indexed: 02/23/2024] Open
Affiliation(s)
- Yong Luo
- School of Pharmaceutical Sciences (Shenzhen), Sun Yat-sen University, Shenzhen, China
| | - Gu Zhan
- State Key Laboratory of Southwestern Chinese Medicine Resources, School of Pharmacy, Chengdu University of Traditional Chinese Medicine, Chengdu, Sichuan, China
| | - Xuefeng Cong
- Institute of Molecular Plus, Tianjin University, Tianjin, China
| | - Hang Zhang
- School of Pharmaceutical Sciences, Zhengzhou University, Zhengzhou, Henan, China
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2
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Al-Karmalawy AA, El-Gamil DS, El-Shesheny R, Sharaky M, Alnajjar R, Kutkat O, Moatasim Y, Elagawany M, Al-Rashood ST, Binjubair FA, Eldehna WM, Noreddin AM, Zakaria MY. Design and statistical optimisation of emulsomal nanoparticles for improved anti-SARS-CoV-2 activity of N-(5-nitrothiazol-2-yl)-carboxamido candidates: in vitro and in silico studies. J Enzyme Inhib Med Chem 2023; 38:2202357. [PMID: 37092260 PMCID: PMC10128464 DOI: 10.1080/14756366.2023.2202357] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 04/25/2023] Open
Abstract
In this article, emulsomes (EMLs) were fabricated to encapsulate the N-(5-nitrothiazol-2-yl)-carboxamido derivatives (3a-3g) in an attempt to improve their biological availability and antiviral activity. Next, both cytotoxicity and anti-SARS-CoV-2 activities of the examined compounds loaded EMLs (F3a-g) were assessed in Vero E6 cells via MTT assay to calculate the CC50 and inhibitory concentration 50 (IC50) values. The most potent 3e-loaded EMLs (F3e) elicited a selectivity index of 18 with an IC50 value of 0.73 μg/mL. Moreover, F3e was selected for further elucidation of a possible mode of action where the results showed that it exhibited a combination of virucidal (>90%), viral adsorption (>80%), and viral replication (>60%) inhibition. Besides, molecular docking and MD simulations towards the SARS-CoV-2 Mpro were performed. Finally, a structure-activity relationship (SAR) study focussed on studying the influence of altering the size, type, and flexibility of the α-substituent to the carboxamide in addition to compound contraction on SARS-CoV-2 activity.HighlightsEmulsomes (EMLs) were fabricated to encapsulate the N-(5-nitrothiazol-2-yl)-carboxamido derivatives (3a-3g).The most potent 3e-loaded EMLs (F3e) showed an IC50 value of 0.73 μg/mL against SARS-CoV-2.F3e exhibited a combination of virucidal (>90%), viral adsorption (>80%), and viral replication (>60%) inhibition.Molecular docking, molecular dynamics (MD) simulations, and MM-GBSA calculations were performed.Structure-activity relationship (SAR) study was discussed to study the influence of altering the size, type, and flexibility of the α-substituent to the carboxamide on the anti-SARS-CoV-2 activity.
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Affiliation(s)
- Ahmed A Al-Karmalawy
- Pharmaceutical Chemistry Department, Faculty of Pharmacy, Ahram Canadian University, Giza, Egypt
| | - Dalia S El-Gamil
- Pharmaceutical Chemistry Department, Faculty of Pharmacy, Ahram Canadian University, Giza, Egypt
| | - Rabeh El-Shesheny
- Water Pollution Research Department, The Center of Scientific Excellence for Influenza Viruses, Environmental Research Institute, National Research Centre, Giza, Egypt
| | - Marwa Sharaky
- Cancer Biology Department, Pharmacology Unit, National Cancer Institute (NCI), Cairo University, Cairo, Egypt
| | - Radwan Alnajjar
- Department of Chemistry, Faculty of Science, University of Benghazi, Benghazi, Libya
- Faculty of Pharmacy, Libyan International Medical University, Benghazi, Libya
- Department of Chemistry, University of Cape Town, Rondebosch, South Africa
| | - Omnia Kutkat
- Water Pollution Research Department, The Center of Scientific Excellence for Influenza Viruses, Environmental Research Institute, National Research Centre, Giza, Egypt
| | - Yassmin Moatasim
- Water Pollution Research Department, The Center of Scientific Excellence for Influenza Viruses, Environmental Research Institute, National Research Centre, Giza, Egypt
| | - Mohamed Elagawany
- Department of Pharmaceutical Chemistry, Faculty of Pharmacy, Damanhour University, Damanhour, Egypt
| | - Sara T Al-Rashood
- Department of Pharmaceutical Chemistry, College of Pharmacy, King Saud University, Riyadh, Saudi Arabia
| | - Faizah A Binjubair
- Department of Pharmaceutical Chemistry, College of Pharmacy, King Saud University, Riyadh, Saudi Arabia
| | - Wagdy M Eldehna
- Department of Pharmaceutical Chemistry, Faculty of Pharmacy, Kafrelsheikh University, Kafrelsheikh, Egypt
- School of Biotechnology, Badr University in Cairo, Badr City, Egypt
| | - Ayman M Noreddin
- Department of Internal Medicine, School of Medicine, University of California Irvine, Irvine, CA, USA
- Department of Clinical Pharmacy, Faculty of Pharmacy, Ahram Canadian University, Giza, Egypt
| | - Mohamed Y Zakaria
- Department of Pharmaceutics and Industrial Pharmacy, Faculty of Pharmacy, Port Said University, Port Said, Egypt
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Jaouadi K, Abdellaoui M, Levernier E, Payard PA, Derat E, Le Saux T, Ollivier C, Torelli S, Jullien L, Plasson R, Fensterbank L, Grimaud L. Regime Switch in the Dual-Catalyzed Coupling of Alkyl Silicates with Aryl Bromides. Chemistry 2023; 29:e202301780. [PMID: 37494564 DOI: 10.1002/chem.202301780] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/03/2023] [Revised: 07/19/2023] [Accepted: 07/25/2023] [Indexed: 07/28/2023]
Abstract
Metallaphotoredox catalyzed cross-coupling of an arylbromide (Ar-Br) with an alkyl bis(catecholato)silicate (R-Si⊖ ) has been analyzed in depth using a continuum of analytical techniques (EPR, fluorine NMR, electrochemistry, photophysics) and modeling (micro-kinetics and DFT calculations). These studies converged on the impact of four control parameters consisting in the initial concentrations of the iridium photocatalyst ([Ir]0 ), nickel precatalyst ([Ni]0 ) and silicate ([R-Si⊖ ]0 ) as well as light intensity I0 for an efficient reaction between Ar-Br and R-Si⊖ . More precisely, two regimes were found to be possibly at play. The first one relies on an equimolar consumption of Ar-Br with R-Si⊖ smoothly leading to Ar-R, with no side-product from R-Si⊖ and a second one in which R-Si⊖ is simultaneously coupled to Ar-Br and degraded to R-H. This integrative approach could serve as a case study for the investigation of other metallaphotoredox catalysis manifolds of synthetic significance.
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Affiliation(s)
- Khaoula Jaouadi
- LBM, Département de chimie, École Normale Supérieure, PSL University, Sorbonne Université, CNRS, 75005, Paris, France
| | - Mehdi Abdellaoui
- Sorbonne Université, CNRS, Institut Parisien de Chimie Moléculaire, 75005, Paris, France
| | - Etienne Levernier
- Sorbonne Université, CNRS, Institut Parisien de Chimie Moléculaire, 75005, Paris, France
| | - Pierre-Adrien Payard
- LBM, Département de chimie, École Normale Supérieure, PSL University, Sorbonne Université, CNRS, 75005, Paris, France
| | - Etienne Derat
- Sorbonne Université, CNRS, Institut Parisien de Chimie Moléculaire, 75005, Paris, France
| | - Thomas Le Saux
- PASTEUR, Département de chimie, École Normale Supérieure, PSL University, Sorbonne Université, CNRS, 75005, Paris, France
| | - Cyril Ollivier
- Sorbonne Université, CNRS, Institut Parisien de Chimie Moléculaire, 75005, Paris, France
| | - Stéphane Torelli
- Univ. Grenoble Alpes, CNRS, CEA, IRIG Laboratoire de Chimie et Biologie des Métaux, 17 rue des Martyrs, 38054, Grenoble Cedex, France
| | - Ludovic Jullien
- PASTEUR, Département de chimie, École Normale Supérieure, PSL University, Sorbonne Université, CNRS, 75005, Paris, France
| | - Raphaël Plasson
- UMR408 SQPOV Avignon Université/INRAE Campus Jean-Henri Fabre, 301 rue Baruch de Spinoza BP, 21239, 84916, Avignon Cedex 9, France
| | - Louis Fensterbank
- Sorbonne Université, CNRS, Institut Parisien de Chimie Moléculaire, 75005, Paris, France
| | - Laurence Grimaud
- LBM, Département de chimie, École Normale Supérieure, PSL University, Sorbonne Université, CNRS, 75005, Paris, France
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4
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Reisenbauer J, Finkelstein P, Ebert MO, Morandi B. Mechanistic Investigation of the Nickel-Catalyzed Transfer Hydrocyanation of Alkynes. ACS Catal 2023; 13:11548-11555. [PMID: 37671177 PMCID: PMC10476158 DOI: 10.1021/acscatal.3c02977] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/30/2023] [Revised: 07/28/2023] [Indexed: 09/07/2023]
Abstract
The implementation of HCN-free transfer hydrocyanation reactions on laboratory scales has recently been achieved by using HCN donor reagents under nickel- and Lewis acid co-catalysis. More recently, malononitrile-based HCN donor reagents were shown to undergo the C(sp3)-CN bond activation by the nickel catalyst in the absence of Lewis acids. However, there is a lack of detailed mechanistic understanding of the challenging C(sp3)-CN bond cleavage step. In this work, in-depth kinetic and computational studies using alkynes as substrates were used to elucidate the overall reaction mechanism of this transfer hydrocyanation, with a particular focus on the activation of the C(sp3)-CN bond to generate the active H-Ni-CN transfer hydrocyanation catalyst. Comparisons of experimentally and computationally derived 13C kinetic isotope effect data support a direct oxidative addition mechanism of the nickel catalyst into the C(sp3)-CN bond facilitated by the coordination of the second nitrile group to the nickel catalyst.
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Affiliation(s)
| | | | | | - Bill Morandi
- ETH Zürich, Vladimir-Prelog-Weg 3, HCI, 8093 Zürich, Switzerland
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5
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Shiri F, Ariafard A. Factors Influencing the Chemoselectivity of Pd(OAc) 2 -Catalyzed Cyclization Reactions Involving 1,6-Enynes as a Substrate and PhI(OAc) 2 as a Reagent. Chemistry 2023; 29:e202300115. [PMID: 37013931 DOI: 10.1002/chem.202300115] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/13/2023] [Indexed: 04/05/2023]
Abstract
It is well documented in the literature that 1,6-enynes are cyclized using PhI(OAc)2 (PIDA) in the presence of Pd(OAc)2 as a catalyst to yield cyclopropyl ketones. In contrast, it has been reported that when 1,6-enynes are substituted by a hydroxy group at the α-position to the alkyne, the chemoselectivity of the cyclization reaction is altered, and polycyclic oxa-heterocycles are formed. This suggests that the hydroxy substituent plays a crucial role in changing the mechanism of the reaction. The aim of this study is to use density functional theory (DFT) calculations at the SMD/M06-D3/def2TZVP//SMD/M06/SDD,6-31G(d) level of theory to shed light on the reason for this change by investigating the detailed mechanistic aspects of these transformations. This study demonstrates that the electronic nature of the Pd catalyst changes from π-philicity to oxophilicity during the catalytic cycle, and this change plays an essential role in controlling the chemoselectivity of the cyclization reactions. In addition, it was found that (1) the hypervalent iodine reagent PIDA serves not only as an oxidant for the oxidation of Pd(II) to Pd(IV), but also as a nucleophile that drives the acetoxypalladation step of the reaction, (2) the oxidation of Pd(II) to Pd(IV) by the iodonium ion [PhIOAc]+ occurs via an interesting mechanism involving coordination of [PhIOAc]+ to the Pd(II) centre, followed by a twist in the hypervalent iodine, and (3) Pd π-complexes are not very susceptible to oxidation. (4) A Pd(II) complex can be six coordinate if the Pd centre is partially oxidized.
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Affiliation(s)
- Farshad Shiri
- Department of Chemistry, Islamic Azad University, Central, Tehran Branch, Poonak, Tehran, 1469669191, Iran
| | - Alireza Ariafard
- Department of Chemistry, Islamic Azad University, Central, Tehran Branch, Poonak, Tehran, 1469669191, Iran
- School of Natural Sciences (Chemistry), University of Tasmania, Private Bag 75, Hobart, TAS, 7001, Australia
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6
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Sebaaly AP, Dias H, Christ L, Merzoud L, Chermette H, Hoffmann G, Morell C. Insight into the Varying Reactivity of Different Catalysts for CO(2) Cycloaddition into Styrene Oxide: An Experimental and DFT Study. Int J Mol Sci 2023; 24. [PMID: 36768447 DOI: 10.3390/ijms24032123] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/06/2022] [Accepted: 12/20/2022] [Indexed: 01/25/2023] Open
Abstract
The cycloaddition of CO2 into epoxides to form cyclic carbonates is a highly sought-after reaction for its potential to both reduce and use CO2, which is a greenhouse gas. In this paper, we present experimental and theoretical studies and a mechanistic approach for three catalytic systems. First, as Lewis base catalysts, imidazole and its derivatives, then as a Lewis acid catalyst, ZnI2 alone, and after that, the combined system of ZnI2 and imidazole. In the former, we aimed to discover the reasons for the varied reactivities of five Lewis base catalysts. Furthermore, we succeeded in reproducing the experimental results and trends using DFT. To add, we emphasized the importance of non-covalent interactions and their role in reactivity. In our case, the presence of a hydrogen bond was a key factor in decreasing the reactivity of some catalysts, thus leading to lower conversion rates. Finally, mechanistically understanding this 100% atom economy reaction can aid experimental chemists in designing better and more efficient catalytic systems.
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Zhang J, Shan R, Xiao H, Hu S, Sheng Z, Qin X, Zhang Y, Wang L, Li J, Zhang C. Electronic Modification by Transitional Metal Dopants to Tune the Oxidation Activity of Pt-CeO 2-Based Catalysts. Environ Sci Technol 2022; 56:17331-17340. [PMID: 36354790 DOI: 10.1021/acs.est.2c07099] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/16/2023]
Abstract
While utilization of transitional metals as a promoter has been extensively studied to enhance the activity of Pt-based catalysts for the oxidation of formaldehyde (HCHO), there is still a lack of well elucidated property-function relationship for the rational selection of a promoter in catalyst design. Herein, we modified a Pt/CeO2 catalyst with two transitional metal dopants (i.e., Mn and Cu) that showed negligible influence on the physical structure of the Pt-CeO2 matrix but distinct effects on the activity of the catalyst. Complementary characterizations combined with density functional theory modeling revealed that the transitional metal dopants significantly modified the electronic structure of the catalyst and shifted the d-band of Pt to higher energy with different extents, which may tune the bonding strength of HCHO/intermediates with the Pt-CeO2 interface domain. The catalyst with moderate bonding strength (i.e., Pt-Mn/CeO2) displayed the highest reactivity under the ambient condition, while Pt-Cu/CeO2 with the highest bonding strength showed a dramatically decreased activity. No correlation was observed between the abundancy of the active oxygen and catalytic activity, likely due to the oxygen supply having a much higher rate than the rate-determining step. This work contributes to the elucidation about the property-function relationship of a transitional metal dopant in Pt-based catalysts for the oxidation of HCHO.
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Affiliation(s)
- Jianghao Zhang
- State Key Joint Laboratory of Environment Simulation and Pollution Control, Research Center for Eco-environmental Sciences, Chinese Academy of Sciences, Beijing 100085, China
| | - Ruoting Shan
- State Key Joint Laboratory of Environment Simulation and Pollution Control, Research Center for Eco-environmental Sciences, Chinese Academy of Sciences, Beijing 100085, China
- Key Laboratory of Catalysis and Energy Materials Chemistry of Ministry of Education & Hubei Key Laboratory of Catalysis and Materials Science, South-Central Minzu University, Wuhan 430074, China
| | - Hongfei Xiao
- State Key Joint Laboratory of Environment Simulation and Pollution Control, Research Center for Eco-environmental Sciences, Chinese Academy of Sciences, Beijing 100085, China
| | - Shuo Hu
- State Key Joint Laboratory of Environment Simulation and Pollution Control, Research Center for Eco-environmental Sciences, Chinese Academy of Sciences, Beijing 100085, China
| | - Zhenteng Sheng
- Key Laboratory of Catalysis and Energy Materials Chemistry of Ministry of Education & Hubei Key Laboratory of Catalysis and Materials Science, South-Central Minzu University, Wuhan 430074, China
| | - Xiaoxiao Qin
- State Key Joint Laboratory of Environment Simulation and Pollution Control, Research Center for Eco-environmental Sciences, Chinese Academy of Sciences, Beijing 100085, China
- University of Chinese Academy of Sciences, Beijing 100049, China
| | - Yuhua Zhang
- Key Laboratory of Catalysis and Energy Materials Chemistry of Ministry of Education & Hubei Key Laboratory of Catalysis and Materials Science, South-Central Minzu University, Wuhan 430074, China
| | - Li Wang
- Key Laboratory of Catalysis and Energy Materials Chemistry of Ministry of Education & Hubei Key Laboratory of Catalysis and Materials Science, South-Central Minzu University, Wuhan 430074, China
| | - Jinlin Li
- Key Laboratory of Catalysis and Energy Materials Chemistry of Ministry of Education & Hubei Key Laboratory of Catalysis and Materials Science, South-Central Minzu University, Wuhan 430074, China
| | - Changbin Zhang
- State Key Joint Laboratory of Environment Simulation and Pollution Control, Research Center for Eco-environmental Sciences, Chinese Academy of Sciences, Beijing 100085, China
- University of Chinese Academy of Sciences, Beijing 100049, China
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8
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Zhang J, Qin X, Chu X, Chen M, Chen X, Chen J, He H, Zhang C. Tuning Metal-Support Interaction of Pt-CeO 2 Catalysts for Enhanced Oxidation Reactivity. Environ Sci Technol 2021; 55:16687-16698. [PMID: 34847319 DOI: 10.1021/acs.est.1c06400] [Citation(s) in RCA: 13] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/13/2023]
Abstract
Metal-support interaction (MSI) has been widely recognized to be playing a pivotal role in regulating the catalytic activity of various reactions. In this work, the degree of MSI between Pt and CeO2 support was finely tuned by adjusting the activation condition, and the obtained catalysts were tested for the oxidative abatement of CO and HCHO under ambient conditions. The characterization of catalysts shows that activation of strongly interacting Pt-CeO2 at higher temperatures by H2 leads to a weaker MSI with increased electron density of Pt, and this modification of local electronic properties is demonstrated to result in enhanced O2 adsorption/activation to prevent the CO self-poisoning effect, while it abates the activity of CO adsorption/activation and oxidation of adsorbed CO. The Pt-CeO2 catalyst with a moderate MSI, which is able to balance each step in the catalytic cycle over Pt and Pt-CeO2 interface domains, displays the highest activity for CO/HCHO oxidation under ambient conditions.
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Affiliation(s)
- Jianghao Zhang
- State Key Joint Laboratory of Environment Simulation and Pollution Control, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing 100085, China
| | - Xiaoxiao Qin
- State Key Joint Laboratory of Environment Simulation and Pollution Control, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing 100085, China
- University of Chinese Academy of Sciences, Beijing 100049, China
| | - Xuefeng Chu
- State Key Joint Laboratory of Environment Simulation and Pollution Control, National Engineering Laboratory for Multi Flue Gas Pollution Control Technology and Equipment, School of Environment, Tsinghua University, Beijing 100084, China
| | - Min Chen
- State Key Joint Laboratory of Environment Simulation and Pollution Control, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing 100085, China
| | - Xueyan Chen
- State Key Joint Laboratory of Environment Simulation and Pollution Control, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing 100085, China
| | - Jianjun Chen
- State Key Joint Laboratory of Environment Simulation and Pollution Control, National Engineering Laboratory for Multi Flue Gas Pollution Control Technology and Equipment, School of Environment, Tsinghua University, Beijing 100084, China
| | - Hong He
- State Key Joint Laboratory of Environment Simulation and Pollution Control, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing 100085, China
- University of Chinese Academy of Sciences, Beijing 100049, China
| | - Changbin Zhang
- State Key Joint Laboratory of Environment Simulation and Pollution Control, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing 100085, China
- University of Chinese Academy of Sciences, Beijing 100049, China
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Xiao J, Cui Y, Li C, Xu H, Zhai Y, Zhang X, Ma S. Room Temperature Allenation of Terminal Alkynes with Aldehydes. Angew Chem Int Ed Engl 2021; 60:25708-25713. [PMID: 34595806 DOI: 10.1002/anie.202109879] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/23/2021] [Revised: 09/17/2021] [Indexed: 11/10/2022]
Abstract
A gold-catalyzed room temperature allenation of terminal alkynes (ATA) with aldehydes affording 1,3-disubstituted allenes with diverse functional groups has been developed by identifying a gold(I) catalyst and an amine. The practicality of this reaction has been demonstrated by a ten gram-scale synthesis and the synthetic potentials have been demonstrated via various transformations and formal total synthesis of (-)-centrolobine. Mechanistic studies revealed that the gold catalyst, the aldehyde effect, the fluoroalkyl hydroxyl solvent (TFE or HFIP) and the structure of amine are vital in this room temperature ATA reaction.
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Affiliation(s)
- Junzhe Xiao
- State Key Laboratory of Organometallic Chemistry, Shanghai Institute of Organic Chemistry, Chinese Academy of Sciences, 345 Lingling Lu, Shanghai, 200032, P. R. China.,University of Chinese Academy of Sciences, Beijing, 100049, P. R. China
| | - Yifan Cui
- State Key Laboratory of Organometallic Chemistry, Shanghai Institute of Organic Chemistry, Chinese Academy of Sciences, 345 Lingling Lu, Shanghai, 200032, P. R. China.,University of Chinese Academy of Sciences, Beijing, 100049, P. R. China
| | - Can Li
- State Key Laboratory of Organometallic Chemistry, Shanghai Institute of Organic Chemistry, Chinese Academy of Sciences, 345 Lingling Lu, Shanghai, 200032, P. R. China.,University of Chinese Academy of Sciences, Beijing, 100049, P. R. China
| | - Haibo Xu
- State Key Laboratory of Organometallic Chemistry, Shanghai Institute of Organic Chemistry, Chinese Academy of Sciences, 345 Lingling Lu, Shanghai, 200032, P. R. China.,University of Chinese Academy of Sciences, Beijing, 100049, P. R. China
| | - Yizhan Zhai
- State Key Laboratory of Organometallic Chemistry, Shanghai Institute of Organic Chemistry, Chinese Academy of Sciences, 345 Lingling Lu, Shanghai, 200032, P. R. China.,University of Chinese Academy of Sciences, Beijing, 100049, P. R. China
| | - Xue Zhang
- State Key Laboratory of Organometallic Chemistry, Shanghai Institute of Organic Chemistry, Chinese Academy of Sciences, 345 Lingling Lu, Shanghai, 200032, P. R. China
| | - Shengming Ma
- State Key Laboratory of Organometallic Chemistry, Shanghai Institute of Organic Chemistry, Chinese Academy of Sciences, 345 Lingling Lu, Shanghai, 200032, P. R. China.,Research Centre for Molecular Recognition and Synthesis, Department of Chemistry, Fudan University, 220 Handan Lu, Shanghai, 200433, P. R. China
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10
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Nnamdi FU, Diner C, Champagne PA, Organ MG. Experimental and Computational Study on the Anti-Markovnikov Hydrofunctionalization of Olefins Using Glycine-Extended AQ-Auxiliaries. Chemistry 2021; 27:3855-3860. [PMID: 33617055 DOI: 10.1002/chem.202004881] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/08/2020] [Indexed: 11/07/2022]
Abstract
Two similar tridentate directing groups derived from glycine and 8-aminoquinoline were shown to enable the palladium-catalyzed anti-Markovnikov hydrofunctionalization of 4-pentenylamine with drastically different efficiencies. A computational investigation into the origin of the reactivity difference between these isomeric, carbonyl-transposed auxiliaries suggests that protonation state, thus charge of the substrate-metal complex prior to nucleopalladation is key. These investigations have culminated in a directing group design that can undergo Pd-catalyzed hydrofunctionalization under relatively mild conditions, as low as room temperature.
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Affiliation(s)
- Fred U Nnamdi
- Centre for Catalysis Research and Innovation (CCRI), Department of Chemistry and Biomolecular Sciences, University of Ottawa, Ottawa, Ontario, K1N 6N5, Canada
| | - Colin Diner
- Centre for Catalysis Research and Innovation (CCRI), Department of Chemistry and Biomolecular Sciences, University of Ottawa, Ottawa, Ontario, K1N 6N5, Canada
| | - Pier Alexandre Champagne
- Department of Chemistry and Environmental Science, New Jersey Institute of Technology, Newark, NJ, 07102, USA
| | - Michael G Organ
- Centre for Catalysis Research and Innovation (CCRI), Department of Chemistry and Biomolecular Sciences, University of Ottawa, Ottawa, Ontario, K1N 6N5, Canada
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Khatua S, Biswas P. Flexible Luminescent MOF: Trapping of Less Stable Conformation of Rotational Isomers, In Situ Guest-Responsive Turn-Off and Turn-On Luminescence and Mechanistic Study. ACS Appl Mater Interfaces 2020; 12:22335-22346. [PMID: 32319280 DOI: 10.1021/acsami.0c02891] [Citation(s) in RCA: 22] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/11/2023]
Abstract
Flexible and dynamic CuI metal-organic framework [Cu(I)-MOF (1)] with well-defined nanoporous channel built with flexible terpyridine ligand offers a scaffold for the inclusion of different classes of guest molecules through a single-crystal-to-single-crystal (SCSC) transformation in the vapor phase at ambient conditions with visual color change. Thus, Cu(I)-MOF (1) offers a potential platform for molecular recognition and undergoes guest-responsive structural dynamism that can be triggered by interfacial interactions. Despite having the stable conformation of the rotational isomers, it selectively encapsulates the less stable conformation (eclipsed and gauche) into its cavity from their vapor phases in the SCSC process. All of the guest-exchanged processes are reversible. It shows selectivity toward less polar guest in a class. The intermediate of all of the guest-exchanged processes appeared as a black material (H2O@Cu(I)-MOF) (1z) prior to the encapsulation of each guest that happens through the SCSC manner followed by encapsulation of the guests replacing H2O in situ at ambient conditions through SCSC transformation. This confirms that the process is a two-step process leading to a common intermediate. The MOF loses its luminescence behavior with H2O removing lattice solvents in situ and appears as a black material, and it regains its luminescence property with the guests replacing H2O. Thus, the MOF displays both luminescence "turn-off" and "turn-on" before and after incorporation of the guests, respectively, leading to a common turn-off mechanism. A fluorescence titration experiment shows selectivity toward aniline among benzene and its derivatives.
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Affiliation(s)
- Sajal Khatua
- School of Chemical Sciences, Indian Association for the Cultivation of Science, 2A & 2B Raja S. C. Mullick Road, Kolkata 700032, West Bengal, India
| | - Protap Biswas
- School of Chemical Sciences, Indian Association for the Cultivation of Science, 2A & 2B Raja S. C. Mullick Road, Kolkata 700032, West Bengal, India
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Buszewski B, Žuvela P, Sagandykova G, Walczak-Skierska J, Pomastowski P, David J, Wong MW. Mechanistic Chromatographic Column Characterization for the Analysis of Flavonoids Using Quantitative Structure-Retention Relationships Based on Density Functional Theory. Int J Mol Sci 2020; 21:E2053. [PMID: 32192096 PMCID: PMC7139519 DOI: 10.3390/ijms21062053] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/14/2020] [Revised: 03/12/2020] [Accepted: 03/13/2020] [Indexed: 11/16/2022] Open
Abstract
This work aimed to unravel the retention mechanisms of 30 structurally different flavonoids separated on three chromatographic columns: conventional Kinetex C18 (K-C18), Kinetex F5 (K-F5), and IAM.PC.DD2. Interactions between analytes and chromatographic phases governing the retention were analyzed and mechanistically interpreted via quantum chemical descriptors as compared to the typical 'black box' approach. Statistically significant consensus genetic algorithm-partial least squares (GA-PLS) quantitative structure retention relationship (QSRR) models were built and comprehensively validated. Results showed that for the K-C18 column, hydrophobicity and solvent effects were dominating, whereas electrostatic interactions were less pronounced. Similarly, for the K-F5 column, hydrophobicity, dispersion effects, and electrostatic interactions were found to be governing the retention of flavonoids. Conversely, besides hydrophobic forces and dispersion effects, electrostatic interactions were found to be dominating the IAM.PC.DD2 retention mechanism. As such, the developed approach has a great potential for gaining insights into biological activity upon analysis of interactions between analytes and stationary phases imitating molecular targets, giving rise to an exceptional alternative to existing methods lacking exhaustive interpretations.
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Affiliation(s)
- Bogusław Buszewski
- Department of Environmental Chemistry and Bioanalytics, Faculty of Chemistry, Gagarina 7, 87-100 Torun, Poland;
- Interdisciplinary Centre for Modern Technologies, Nicolaus Copernicus University, Wileńska 4, 87-100 Torun, Poland; (J.W.-S.); (P.P.)
| | - Petar Žuvela
- Department of Chemistry, National University of Singapore, 3 Science Drive 3, Singapore 117543, Singapore; (P.Ž.); (J.D.)
| | - Gulyaim Sagandykova
- Department of Environmental Chemistry and Bioanalytics, Faculty of Chemistry, Gagarina 7, 87-100 Torun, Poland;
- Interdisciplinary Centre for Modern Technologies, Nicolaus Copernicus University, Wileńska 4, 87-100 Torun, Poland; (J.W.-S.); (P.P.)
| | - Justyna Walczak-Skierska
- Interdisciplinary Centre for Modern Technologies, Nicolaus Copernicus University, Wileńska 4, 87-100 Torun, Poland; (J.W.-S.); (P.P.)
| | - Paweł Pomastowski
- Interdisciplinary Centre for Modern Technologies, Nicolaus Copernicus University, Wileńska 4, 87-100 Torun, Poland; (J.W.-S.); (P.P.)
| | - Jonathan David
- Department of Chemistry, National University of Singapore, 3 Science Drive 3, Singapore 117543, Singapore; (P.Ž.); (J.D.)
| | - Ming Wah Wong
- Department of Chemistry, National University of Singapore, 3 Science Drive 3, Singapore 117543, Singapore; (P.Ž.); (J.D.)
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13
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Al-Hussaini L, Launay F, Galvez E. Vanadium-Substituted Phosphomolybdic Acids for the Aerobic Cleavage of Lignin Models-Mechanistic Aspect and Extension to Lignin. Materials (Basel) 2020; 13:ma13040812. [PMID: 32053950 PMCID: PMC7079653 DOI: 10.3390/ma13040812] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 01/23/2020] [Revised: 02/07/2020] [Accepted: 02/07/2020] [Indexed: 06/10/2023]
Abstract
This work deals with the aerobic oxidative cleavage of C-C and C-O bonds catalyzed by the Keggin-type phosphovanadomolybdic acid (H6[PMo9V3O40], noted H6PV3). The latter was synthesized by an adapted hydrothermal procedure classically used for lower vanadium content and was tested as a catalyst for the aerobic cleavage of 2-phenoxyacetophenone (noted K1HH) and 1-phenyl-2-phenoxyethanol (A1HH) used as two lignin models. The operative conditions (solvent, catalytic loading, etc.) were adjusted on K1HH and extrapolated to A1HH. The cleavage of the alcohol model required more drastic conditions and therefore further optimization. Preliminary attempts on an Organosolv wheat straw lignin were performed too. From the kinetic study, high performance liquid chromatography (HPLC) and gas chromatography-mass spectrometry (GC-MS) data, a mechanism of the cleavage of both models was proposed.
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Affiliation(s)
- Louay Al-Hussaini
- Centre National de la Recherche Scientifique, UMR 7197, Laboratoire de Réactivité de Surface (LRS), Sorbonne Université, F-75005 Paris, France;
- Centre National de la Recherche Scientifique, UMR 7190, Institut Jean le Rond d’Alembert, Sorbonne Université, F-75005 Paris, France;
| | - Franck Launay
- Centre National de la Recherche Scientifique, UMR 7197, Laboratoire de Réactivité de Surface (LRS), Sorbonne Université, F-75005 Paris, France;
| | - Elena Galvez
- Centre National de la Recherche Scientifique, UMR 7190, Institut Jean le Rond d’Alembert, Sorbonne Université, F-75005 Paris, France;
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14
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Ding S, Xu L, Miao Z. Unsymmetrical Diboron Reagents: Application in Borylation Reactions of Unsaturated Bonds. Molecules 2019; 24:E1325. [PMID: 30987277 DOI: 10.3390/molecules24071325] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/14/2019] [Revised: 03/29/2019] [Accepted: 04/01/2019] [Indexed: 01/04/2023] Open
Abstract
In the past decades, borylation reactions have received extensive research interest and have developed into effective tools in the synthesis of versatile organoboron compounds. Boranes and symmetrical diboron compounds are commonly utilized as borylating reagents in these transformations, especially in the borylation reactions of unsaturated bonds. More recently, several types of unsymmetrical diboron reagents have been synthesized and applied in these borylation reactions, allowing for complementary chemo- and regioselectivity. This review aimed to highlight the recent development in this rising research field, focusing on new reactivity and selectivity that originates from the use of these unsymmetrical diboron reagents.
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15
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Zhou B, Huang J, Yan L, Liu X, Song N, Tao L, Zhang Q. Probing Energy Migration through Precise Control of Interfacial Energy Transfer in Nanostructure. Adv Mater 2019; 31:e1806308. [PMID: 30548941 DOI: 10.1002/adma.201806308] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/29/2018] [Revised: 11/17/2018] [Indexed: 06/09/2023]
Abstract
A novel mechanistic strategy for probing the energy migration through constructing the interfacial energy transfer (IET) in a core-shell-shell nanostructure is reported. In this design, the trilayer nanostructure is composed of a sensitizing core, a migratory interlayer, and a detective shell layer that interact with each other only by IET and the latter two shell layers are nonresponsive to the incident irradiation. This model is well applied in investigating the energy migration over the Tb, Gd, and Yb sublattices, and the results show that the Gd sublattice holds the best energy migratory performance. Moreover, the finding of energy migration over the Yb sublattice enables the 808 nm excited long-lived upconversion of Tb3+ and Eu3+ , which exhibits unique time-gating performance for information security. The results provide a facile and powerful nanosized model for an in-depth understanding of the fundamentals involving lanthanide interactions, which will further help excite new chances for the frontier applications of lanthanide-based luminescent materials.
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Affiliation(s)
- Bo Zhou
- State Key Laboratory of Luminescent Materials and Devices, Guangdong Provincial Key Laboratory of Fiber Laser Materials and Applied Techniques, and Institute of Optical Communication Materials, South China University of Technology, Guangzhou, 510641, China
| | - Jinshu Huang
- State Key Laboratory of Luminescent Materials and Devices, Guangdong Provincial Key Laboratory of Fiber Laser Materials and Applied Techniques, and Institute of Optical Communication Materials, South China University of Technology, Guangzhou, 510641, China
| | - Long Yan
- State Key Laboratory of Luminescent Materials and Devices, Guangdong Provincial Key Laboratory of Fiber Laser Materials and Applied Techniques, and Institute of Optical Communication Materials, South China University of Technology, Guangzhou, 510641, China
| | - Xuelong Liu
- State Key Laboratory of Luminescent Materials and Devices, Guangdong Provincial Key Laboratory of Fiber Laser Materials and Applied Techniques, and Institute of Optical Communication Materials, South China University of Technology, Guangzhou, 510641, China
| | - Nan Song
- State Key Laboratory of Luminescent Materials and Devices, Guangdong Provincial Key Laboratory of Fiber Laser Materials and Applied Techniques, and Institute of Optical Communication Materials, South China University of Technology, Guangzhou, 510641, China
| | - Lili Tao
- School of Materials and Energy, Guangdong University of Technology, Guangzhou, 510006, China
| | - Qinyuan Zhang
- State Key Laboratory of Luminescent Materials and Devices, Guangdong Provincial Key Laboratory of Fiber Laser Materials and Applied Techniques, and Institute of Optical Communication Materials, South China University of Technology, Guangzhou, 510641, China
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16
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Song N, Zhou B, Yan L, Huang J, Zhang Q. Understanding the Role of Yb 3+ in the Nd/Yb Coupled 808-nm-Responsive Upconversion. Front Chem 2019; 6:673. [PMID: 30740392 PMCID: PMC6355672 DOI: 10.3389/fchem.2018.00673] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/30/2018] [Accepted: 12/24/2018] [Indexed: 12/15/2022] Open
Abstract
The realization of upconversion at 808 nm excitation has shown great advantages in advancing the broad bioapplications of lanthanide-doped nanomaterials. In an 808 nm responsive system, Nd3+ and Yb3+ are both needed where Nd3+ acts as a sensitizer through absorbing the excitation irradiation. However, few studies have been dedicated to the role of Yb3+. Here, we report a systemic investigation on the role of Yb3+ by designing a set of core-shell-based nanostructures. We find that energy migration over the ytterbium sublattice plays a key role in facilitating the energy transportation, and moreover, we show that the interfacial energy transfer occurring at the core-shell interface also has a contribution to the upconversion. By optimizing the dopant concentration and surface anchoring the infrared indocyanine green dye, the 808 nm responsive upconversion is markedly enhanced. These results present an in-depth understanding of the fundamental interactions among lanthanides, and more importantly, they offer new possibilities to tune and control the upconversion of lanthanide-based luminescent materials.
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Affiliation(s)
| | - Bo Zhou
- State Key Laboratory of Luminescent Materials and Devices, Guangdong Provincial Key Laboratory of Fiber Laser Materials and Applied Techniques, Institute of Optical Communication Materials, South China University of Technology, Guangzhou, China
| | | | | | - Qinyuan Zhang
- State Key Laboratory of Luminescent Materials and Devices, Guangdong Provincial Key Laboratory of Fiber Laser Materials and Applied Techniques, Institute of Optical Communication Materials, South China University of Technology, Guangzhou, China
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17
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Panda A, Sharma PK, Narasimha Murthy S. Effect of Mild Hyperthermia on Transdermal Absorption of Nicotine from Patches. AAPS PharmSciTech 2019; 20:77. [PMID: 30635802 DOI: 10.1208/s12249-019-1299-x] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/28/2018] [Accepted: 12/26/2018] [Indexed: 11/30/2022] Open
Abstract
Application of heat (hyperthermic conditions) on skin is known to enhance drug transfer and facilitate skin penetration of molecules. The aim of this work was to study the effect of hyperthermia on the drug release and skin permeation from nicotine transdermal patches. The drug release and skin permeation were characterized by in vitro release test and in vitro permeation test. The temperature was maintained at 32 °C as control (simulating normal physiological skin temperature) and 42 °C as hyperthermia condition. The in vitro release test was carried out using USP apparatus 5-Paddle over disk method for a transdermal patch. Skin permeation study was carried out across porcine skin using the flow through cells (PermeGear, Inc.) with an active diffusion area of 0.94 cm2. Mechanistic studies (parameters such as partition coefficient, TEWL and electrical resistivity) were also performed to understand the mechanisms involved in determining the influence of hyperthermia on drug delivery from transdermal patches of nicotine. The rate and extent of drug release from nicotine patch was not significantly different at two temperatures (Cumulative release after 12 h was 43.99 ± 3.29% at 32 °C and 53.70 ± 5.14% at 42 °C). Whereas, in case of in vitro permeation studies, the nicotine transdermal permeation flux for patch was threefold higher at 42 °C (100.1 ± 14.83 μg/cm2/h) than at 32 °C (33.3 ± 14.83 μg/cm2/h). The mechanistic studies revealed that the predominant mechanism of enhancement of drug permeation by hyperthermia condition is by the way of increasing the skin permeability. There is a potential concern of dumping of higher dose of nicotine via transdermal route.
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18
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Kankala S, Thota N, Björkling F, Taylor MK, Vadde R, Balusu R. Silver carbene complexes: An emerging class of anticancer agents. Drug Dev Res 2018; 80:188-199. [PMID: 30387164 DOI: 10.1002/ddr.21478] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/11/2018] [Revised: 09/19/2018] [Accepted: 09/20/2018] [Indexed: 12/15/2022]
Abstract
Cancer is a major global health problem with large therapeutic challenges. Although substantial progress has been made in cancer therapy, there still remains a need to develop novel and effective treatment strategies to treat several relapsed and refractory cancers. Recently, there has been growing demand for considering organometallics as antineoplastic agents. This review is focused on a group of organometallics, silver N-heterocyclic carbene complexes (SCCs) and their anticancer efficacy in targeting multiple pathways in various in vitro cancer model systems. However, the precise molecular mechanism of SCCs anticancer properties remains unclear. Here, we discuss the SCCs chemistry, potential molecular targets, possible molecular mechanism of action, and their application in cancer therapies.
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Affiliation(s)
| | - Niranjan Thota
- Department of Drug Design and Pharmacology, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark
| | - Fredrik Björkling
- Department of Drug Design and Pharmacology, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark
| | - Myles K Taylor
- University of Kansas Medical Center, Kansas City, Kansas
| | - Ravinder Vadde
- Department of Chemistry, Kakatiya University, Warangal, Telangana State, India
| | - Ramesh Balusu
- University of Kansas Medical Center, Kansas City, Kansas.,Division of Hematologic Malignancies and Cellular Therapeutics, Department of Internal Medicine, University of Kansas Medical Center, Kansas City, Kansas
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19
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Chipman A, Gouranourimi A, Farshadfar K, Olding A, Yates BF, Ariafard A. A Computational Mechanistic Investigation into Reduction of Gold(III) Complexes by Amino Acid Glycine: A New Variant for Amine Oxidation. Chemistry 2018; 24:8361-8368. [PMID: 29655208 DOI: 10.1002/chem.201800403] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/26/2018] [Revised: 04/02/2018] [Indexed: 01/10/2023]
Abstract
Density functional theory (DFT) was utilized to explore the reduction of gold(III) complexes by the amino acid glycine (Gly). Interestingly, when the nitrogen atom of Gly coordinates to the gold(III) center, its Cα -hydrogen atom becomes so acidic that it can be easily deprotonated by a mild base like water. The deprotonation converts the amino acid into a potent reductant by which gold(III) is reduced to gold(I) with a moderate activation energy. To our knowledge, this is the first contribution suggesting that primary amines are oxidized to imines via direct α-carbon deprotonation. This finding may provide new insights into the mechanistic interpretation of amine oxidations catalyzed/mediated by a center with high cathodic reduction potential. This work also provides a rationalization behind why gold(III) complexes with amine-based polydentate ligands are reluctant to undergo a redox process. Gold(III) reduction occurs most efficiently if the Cα proton leaves in the plane of the Cα , N and Au atoms. Chelation prevents this alignment, resulting in the gold(III) complex being unreactive toward reduction. It has been experimentally found that gold(III) is capable of oxidizing Gly to glyoxylic acid (GA) as the initial product. The latter, in the presence of another gold(III) complex, has been reported to undergo oxidative decarboxylation to afford CO2 and HCOOH. This process is found to be mediated by formation of a geminal diol intermediate produced by reaction of water with the aldehyde functional group of the coordinated GA.
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Affiliation(s)
- Antony Chipman
- School of Physical Sciences (Chemistry), University of Tasmania, Private Bag 75, Hobart, TAS, 7001, Australia
| | - Ali Gouranourimi
- School of Physical Sciences (Chemistry), University of Tasmania, Private Bag 75, Hobart, TAS, 7001, Australia
| | - Kaveh Farshadfar
- Department of Chemistry, Islamic Azad University, Central Tehran Branch, Shohrak Gharb, Tehran, Iran
| | - Angus Olding
- School of Physical Sciences (Chemistry), University of Tasmania, Private Bag 75, Hobart, TAS, 7001, Australia
| | - Brian F Yates
- School of Physical Sciences (Chemistry), University of Tasmania, Private Bag 75, Hobart, TAS, 7001, Australia
| | - Alireza Ariafard
- School of Physical Sciences (Chemistry), University of Tasmania, Private Bag 75, Hobart, TAS, 7001, Australia.,Department of Chemistry, Islamic Azad University, Central Tehran Branch, Shohrak Gharb, Tehran, Iran
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20
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Stridfeldt E, Lindstedt E, Reitti M, Blid J, Norrby P, Olofsson B. Competing Pathways in O-Arylations with Diaryliodonium Salts: Mechanistic Insights. Chemistry 2017; 23:13249-13258. [PMID: 28792102 PMCID: PMC5639379 DOI: 10.1002/chem.201703057] [Citation(s) in RCA: 46] [Impact Index Per Article: 6.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/03/2017] [Indexed: 01/11/2023]
Abstract
A mechanistic study of arylations of aliphatic alcohols and hydroxide with diaryliodonium salts, to give alkyl aryl ethers and diaryl ethers, has been performed using experimental techniques and DFT calculations. Aryne intermediates have been trapped, and additives to avoid by-product formation originating from arynes have been found. An alcohol oxidation pathway was observed in parallel to arylation; this is suggested to proceed by an intramolecular mechanism. Product formation pathways via ligand coupling and arynes have been compared, and 4-coordinated transition states were found to be favored in reactions with alcohols. Furthermore, a novel, direct nucleophilic substitution pathway has been identified in reactions with electron-deficient diaryliodonium salts.
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Affiliation(s)
- Elin Stridfeldt
- Department of Organic ChemistryArrhenius LaboratoryStockholm University106 91StockholmSweden
| | - Erik Lindstedt
- Department of Organic ChemistryArrhenius LaboratoryStockholm University106 91StockholmSweden
| | - Marcus Reitti
- Department of Organic ChemistryArrhenius LaboratoryStockholm University106 91StockholmSweden
| | - Jan Blid
- Department of Organic ChemistryArrhenius LaboratoryStockholm University106 91StockholmSweden
| | - Per‐Ola Norrby
- Pharmaceutical SciencesAstraZeneca Gothenburg431 83MölndalSweden
| | - Berit Olofsson
- Department of Organic ChemistryArrhenius LaboratoryStockholm University106 91StockholmSweden
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21
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Homs A, Obradors C, Lebœuf D, Echavarren AM. Dissecting Anion Effects in Gold(I)-Catalyzed Intermolecular Cycloadditions. Adv Synth Catal 2014; 356:221-228. [PMID: 26190958 PMCID: PMC4498468 DOI: 10.1002/adsc.201300704] [Citation(s) in RCA: 79] [Impact Index Per Article: 7.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/04/2013] [Revised: 10/10/2013] [Indexed: 12/13/2022]
Abstract
From a series of gold complexes of the type [t-BuXPhosAu(MeCN)]X (X=anion), the best results in intermolecular gold(I)-catalyzed reactions are obtained with the complex with the bulky and soft anion BAr4F- [BAr4F-=3,5-bis(trifluoromethyl)phenylborate] improving the original protocols by 10-30% yield. A kinetic study on the [2+2] cycloaddition reaction of alkynes with alkenes is consistent with an scenario in which the rate-determining step is the ligand exchange to generate the (η2-phenylacetylene)gold(I) complex. We have studied in detail the subtle differences that can be attributed to the anion in this formation, which result in a substantial decrease in the formation of unproductive σ,π-(alkyne)digold(I) complexes by destabilizing the conjugated acid formed.
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Affiliation(s)
- Anna Homs
- Institute of Chemical Research of Catalonia (ICIQ), Av. Països Catalans 16 43007 Tarragona, Spain, ; e-mail:
| | - Carla Obradors
- Institute of Chemical Research of Catalonia (ICIQ), Av. Països Catalans 16 43007 Tarragona, Spain, ; e-mail:
| | - David Lebœuf
- Institute of Chemical Research of Catalonia (ICIQ), Av. Països Catalans 16 43007 Tarragona, Spain, ; e-mail:
| | - Antonio M Echavarren
- Institute of Chemical Research of Catalonia (ICIQ), Av. Països Catalans 16 43007 Tarragona, Spain, ; e-mail: ; Departament de Química Analítica i Química Orgànica, Universitat Rovira i Virgili C/Marcel⋅li Domingo s/n, 43007 Tarragona, Spain
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22
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Abstract
The mechanism of the reaction of CuFL1 (FL1 = 2-{2-chloro-6-hydroxy-5-[(2-methylquinolin-8-ylamino)methyl]-3-oxo-3H-xanthen-9-yl}benzoic acid) with nitric oxide (NO) to form the N-nitrosated product FL1-NO in buffered aqueous solutions was investigated. The reaction is first-order in [CuFL1], [NO], and [OH(-)]. The observed rate saturation at high base concentrations is consistent with a mechanism in which the protonation state of the secondary amine of the ligand is important for reactivity. This information provides a rationale for designing faster-reacting probes by lowering the pK(a) of the secondary amine. Activation parameters for the reaction of CuFL1 with NO indicate an associative mechanism (DeltaS(double dagger) = -120 +/- 10 J/mol.K) with a modest thermal barrier (DeltaH(double dagger) = 41 +/- 2 kJ/mol; E(a) = 43 +/- 2 kJ/mol). Variable-pH electron paramagnetic resonance experiments reveal that, as the secondary amine of CuFL1 is deprotonated, electron density shifts to yield a new spin-active species having electron density localized on the deprotonated amine nitrogen atom. This result suggests that FL1-NO formation occurs when NO attacks the deprotonated secondary amine of the coordinated ligand, followed by inner-sphere electron transfer to Cu(II) to form Cu(I) and release of FL1-NO from the metal.
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Affiliation(s)
- Lindsey E. McQuade
- Contribution from the Department of Chemistry, Massachusetts Institute of Technology, Cambridge, Massachusetts 02139
| | - Michael D. Pluth
- Contribution from the Department of Chemistry, Massachusetts Institute of Technology, Cambridge, Massachusetts 02139
| | - Stephen J. Lippard
- Contribution from the Department of Chemistry, Massachusetts Institute of Technology, Cambridge, Massachusetts 02139
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23
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Abraham CJ, Paull DH, Bekele T, Scerba MT, Dudding T, Lectka T. A surprising mechanistic "switch" in Lewis acid activation: a bifunctional, asymmetric approach to alpha-hydroxy acid derivatives. J Am Chem Soc 2008; 130:17085-94. [PMID: 19053448 PMCID: PMC2651146 DOI: 10.1021/ja806818a] [Citation(s) in RCA: 50] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
We report a detailed synthetic and mechanistic study of an unusual bifunctional, sequential hetero-Diels-Alder/ring-opening reaction in which chiral, metal complexed ketene enolates react with o-quinones to afford highly enantioenriched, alpha-hydroxylated carbonyl derivatives in excellent yield. A number of Lewis acids were screened in tandem with cinchona alkaloid derivatives; surprisingly, trans-(Ph(3)P)(2)PdCl(2) was found to afford the most dramatic increase in yield and rate of reaction. A series of Lewis acid binding motifs were explored through molecular modeling, as well as IR, UV, and NMR spectroscopy. Our observations document a fundamental mechanistic "switch", namely the formation of a tandem Lewis base/Lewis acid activated metal enolate in preference to a metal-coordinated quinone species (as observed in other reactions of o-quinone derivatives). This new method was applied to the syntheses of several pharmaceutical targets, each of which was obtained in high yield and enantioselectivity.
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Affiliation(s)
- Ciby J. Abraham
- Department of Chemistry, New Chemistry Building, Johns Hopkins University, 3400 North Charles Street, Baltimore, Maryland 21218, and Department of Chemistry, Brock University, St. Catharines, Ontario L2S 3A1, Canada
| | - Daniel H. Paull
- Department of Chemistry, New Chemistry Building, Johns Hopkins University, 3400 North Charles Street, Baltimore, Maryland 21218, and Department of Chemistry, Brock University, St. Catharines, Ontario L2S 3A1, Canada
| | | | - Michael T. Scerba
- Department of Chemistry, New Chemistry Building, Johns Hopkins University, 3400 North Charles Street, Baltimore, Maryland 21218, and Department of Chemistry, Brock University, St. Catharines, Ontario L2S 3A1, Canada
| | | | - Thomas Lectka
- Department of Chemistry, New Chemistry Building, Johns Hopkins University, 3400 North Charles Street, Baltimore, Maryland 21218, and Department of Chemistry, Brock University, St. Catharines, Ontario L2S 3A1, Canada
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