1
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Young YA, Nguyen HTH, Nguyen HD, Ganguly T, Nguyen YH, Do LH. A ratiometric substrate for rapid evaluation of transfer hydrogenation efficiency in solution. Dalton Trans 2024; 53:8887-8892. [PMID: 38757518 PMCID: PMC11160331 DOI: 10.1039/d4dt00891j] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/18/2024]
Abstract
A cyclometalated iridium(III) complex bearing a self-immolative quinolinium moiety was developed as a ratiometric substrate for transfer hydrogenation studies. This photoluminescent probe allowed the rapid screening of a variety of Ir catalysts using a microplate reader, offering a convenient method to assess activity using a minimum amount of catalyst sample.
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Affiliation(s)
- Yen-An Young
- Department of Chemistry, University of Houston, 4800 Calhoun Road, Houston, TX 77204, USA.
| | - Huong T H Nguyen
- Department of Chemistry, University of Houston, 4800 Calhoun Road, Houston, TX 77204, USA.
| | - Hieu D Nguyen
- Department of Chemistry, University of Houston, 4800 Calhoun Road, Houston, TX 77204, USA.
| | - Tuhin Ganguly
- Department of Chemistry, University of Houston, 4800 Calhoun Road, Houston, TX 77204, USA.
| | - Yennie H Nguyen
- Department of Chemistry, University of Houston, 4800 Calhoun Road, Houston, TX 77204, USA.
| | - Loi H Do
- Department of Chemistry, University of Houston, 4800 Calhoun Road, Houston, TX 77204, USA.
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2
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Crossley SWM, Tenney L, Pham VN, Xie X, Zhao MW, Chang CJ. A Transfer Hydrogenation Approach to Activity-Based Sensing of Formate in Living Cells. J Am Chem Soc 2024; 146:8865-8876. [PMID: 38470125 DOI: 10.1021/jacs.3c09735] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 03/13/2024]
Abstract
Formate is a major reactive carbon species in one-carbon metabolism, where it serves as an endogenous precursor for amino acid and nucleic acid biosynthesis and a cellular source of NAD(P)H. On the other hand, aberrant elevations in cellular formate are connected to progression of serious diseases, including cancer and Alzheimer's disease. Traditional methods for formate detection in biological environments often rely on sample destruction or extensive processing, resulting in a loss of spatiotemporal information. To help address these limitations, here we present the design, synthesis, and biological evaluation of a first-generation activity-based sensing system for live-cell formate imaging that relies on iridium-mediated transfer hydrogenation chemistry. Formate facilitates an aldehyde-to-alcohol conversion on various fluorophore scaffolds to enable fluorescence detection of this one-carbon unit, including through a two-color ratiometric response with internal calibration. The resulting two-component probe system can detect changes in formate levels in living cells with a high selectivity over potentially competing biological analytes. Moreover, this activity-based sensing system can visualize changes in endogenous formate fluxes through alterations of one-carbon pathways in cell-based models of human colon cancer, presaging the potential utility of this chemical approach to probe the continuum between one-carbon metabolism and signaling in cancer and other diseases.
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3
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Chirila A, Hu Y, Linehan JC, Dixon DA, Wiedner ES. Thermodynamic and Kinetic Activity Descriptors for the Catalytic Hydrogenation of Ketones. J Am Chem Soc 2024; 146:6866-6879. [PMID: 38437011 DOI: 10.1021/jacs.3c13876] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 03/05/2024]
Abstract
Activity descriptors are a powerful tool for the design of catalysts that can efficiently utilize H2 with minimal energy losses. In this study, we develop the use of hydricity and H- self-exchange rates as thermodynamic and kinetic descriptors for the hydrogenation of ketones by molecular catalysts. Two complexes with known hydricity, HRh(dmpe)2 and HCo(dmpe)2, were investigated for the catalytic hydrogenation of ketones under mild conditions (1.5 atm and 25 °C). The rhodium catalyst proved to be an efficient catalyst for a wide range of ketones, whereas the cobalt catalyst could only hydrogenate electron-deficient ketones. Using a combination of experiment and electronic structure theory, thermodynamic hydricity values were established for 46 alkoxide/ketone pairs in both acetonitrile and tetrahydrofuran solvents. Through comparison of the hydricities of the catalysts and substrates, it was determined that catalysis was observed only for catalyst/ketone pairs with an exergonic H- transfer step. Mechanistic studies revealed that H- transfer was the rate-limiting step for catalysis, allowing for the experimental and computation construction of linear free-energy relationships (LFERs) for H- transfer. Further analysis revealed that the LFERs could be reproduced using Marcus theory, in which the H- self-exchange rates for the HRh/Rh+ and ketone/alkoxide pairs were used to predict the experimentally measured catalytic barriers within 2 kcal mol-1. These studies significantly expand the scope of catalytic reactions that can be analyzed with a thermodynamic hydricity descriptor and firmly establish Marcus theory as a valid approach to develop kinetic descriptors for designing catalysts for H- transfer reactions.
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Affiliation(s)
- Andrei Chirila
- Institute for Integrated Catalysis, Pacific Northwest National Laboratory, Richland, Washington 99352, United States
| | - Yiqin Hu
- Department of Chemistry and Biochemistry, University of Alabama, Tuscaloosa, Alabama 35487, United States
| | - John C Linehan
- Institute for Integrated Catalysis, Pacific Northwest National Laboratory, Richland, Washington 99352, United States
| | - David A Dixon
- Department of Chemistry and Biochemistry, University of Alabama, Tuscaloosa, Alabama 35487, United States
| | - Eric S Wiedner
- Institute for Integrated Catalysis, Pacific Northwest National Laboratory, Richland, Washington 99352, United States
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4
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Nguyen HD, Jana RD, Campbell DT, Tran TV, Do LH. Lewis acid-driven self-assembly of diiridium macrocyclic catalysts imparts substrate selectivity and glutathione tolerance. Chem Sci 2023; 14:10264-10272. [PMID: 37772092 PMCID: PMC10530542 DOI: 10.1039/d3sc02836d] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/02/2023] [Accepted: 09/02/2023] [Indexed: 09/30/2023] Open
Abstract
Molecular inorganic catalysts (MICs) tend to have solvent-exposed metal centers that lack substrate specificity and are easily inhibited by biological nucleophiles. Unfortunately, these limitations exclude many MICs from being considered for in vivo applications. To overcome this challenge, a strategy to spatially confine MICs using Lewis acid-driven self-assembly is presented. It was shown that in the presence of external cations (e.g., Li+, Na+, K+, or Cs+) or phosphate buffered saline, diiridium macrocycles spontaneously formed supramolecular iridium-cation species, which were characterized by X-ray crystallography and dynamic light scattering. These nanoassemblies selectively reduced sterically unhindered C[double bond, length as m-dash]O groups via transfer hydrogenation and tolerated up to 1 mM of glutathione. In contrast, when non-coordinating tetraalkylammonium cations were used, the diiridium catalysts were unable to form higher-ordered structures and discriminate between different aldehyde substrates. This work suggests that in situ coordination self-assembly could be a versatile approach to enable or enhance the integration of MICs with biological hosts.
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Affiliation(s)
- Hieu D Nguyen
- Department of Chemistry, University of Houston 4800 Calhoun Road Houston Texas USA
| | - Rahul D Jana
- Department of Chemistry, University of Houston 4800 Calhoun Road Houston Texas USA
| | - Dylan T Campbell
- Department of Chemistry, University of Houston 4800 Calhoun Road Houston Texas USA
| | - Thi V Tran
- Department of Chemistry, University of Houston 4800 Calhoun Road Houston Texas USA
| | - Loi H Do
- Department of Chemistry, University of Houston 4800 Calhoun Road Houston Texas USA
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5
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Kelani MT, Muller A, Lammertsma K. (2,2'-Bipyrid-yl)(η 6- p-cymene)iodidoruthenium(II) hexa-fluorido-phosphate. IUCRDATA 2023; 8:x230392. [PMID: 37287858 PMCID: PMC10242728 DOI: 10.1107/s2414314623003929] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/28/2023] [Accepted: 05/02/2023] [Indexed: 06/09/2023] Open
Abstract
The title compound, having the mol-ecular formula [RuI(η6-C10H14)(C10H8N2)]PF6, crystallizes in the triclinic P (Z = 2) space group as a half-sandwich complex resembling a three-legged piano stool. Important geometrical parameters include Ru-cymene centroid = 1.6902 (17) Å, Ru-I = 2.6958 (5) Å, [Ru-N]avg = 2.072 (3) Å, N1-Ru-N2 = 76.86 (12)° and a dihedral angle between the planes of the two rings of the bipyridyl system of 5.9 (2)°. The PF6 - ion was treated with a twofold disorder model, refining to a 65.0 (8):35.0 (8) occupancy ratio. The crystal packing features C-H⋯F/I inter-actions.
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Affiliation(s)
- Monsuru T. Kelani
- Department of Chemical Sciences, University of Johannesburg, Auckland Park, Johannesburg 2006, South Africa
| | - Alfred Muller
- Department of Chemical Sciences, University of Johannesburg, Auckland Park, Johannesburg 2006, South Africa
| | - Koop Lammertsma
- Department of Chemical Sciences, University of Johannesburg, Auckland Park, Johannesburg 2006, South Africa
- Department of Chemistry and Pharmaceutical Sciences, Faculty of Sciences, Vrije Universiteit Amsterdam, De Boelelaan 1083, 1081 HV Amsterdam, The Netherlands
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6
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Turan N, Akdeniz A. Synthesis, Structural Characterization of Schiff Base Ligands and Their RuII‐p‐Cymene Complexes, and Catalytic Activity in the Transfer Hydrogenation of Ketones. Catal Letters 2022. [DOI: 10.1007/s10562-022-04222-w] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
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7
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Espinosa MR, Ertem MZ, Barakat M, Bruch QJ, Deziel AP, Elsby MR, Hasanayn F, Hazari N, Miller AJM, Pecoraro MV, Smith AM, Smith NE. Correlating Thermodynamic and Kinetic Hydricities of Rhenium Hydrides. J Am Chem Soc 2022; 144:17939-17954. [PMID: 36130605 DOI: 10.1021/jacs.2c07192] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
The kinetics of hydride transfer from Re(Rbpy)(CO)3H (bpy = 4,4'-R-2,2'-bipyridine; R = OMe, tBu, Me, H, Br, COOMe, CF3) to CO2 and seven different cationic N-heterocycles were determined. Additionally, the thermodynamic hydricities of complexes of the type Re(Rbpy)(CO)3H were established primarily using computational methods. Linear free-energy relationships (LFERs) derived by correlating thermodynamic and kinetic hydricities indicate that, in general, the rate of hydride transfer increases as the thermodynamic driving force for the reaction increases. Kinetic isotope effects range from inverse for hydride transfer reactions with a small driving force to normal for reactions with a large driving force. Hammett analysis indicates that hydride transfer reactions with greater thermodynamic driving force are less sensitive to changes in the electronic properties of the metal hydride, presumably because there is less buildup of charge in the increasingly early transition state. Bronsted α values were obtained for a range of hydride transfer reactions and along with DFT calculations suggest the reactions are concerted, which enables the use of Marcus theory to analyze hydride transfer reactions involving transition metal hydrides. It is notable, however, that even slight perturbations in the steric properties of the Re hydride or the hydride acceptor result in large deviations in the predicted rate of hydride transfer based on thermodynamic driving forces. This indicates that thermodynamic considerations alone cannot be used to predict the rate of hydride transfer, which has implications for catalyst design.
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Affiliation(s)
- Matthew R Espinosa
- Department of Chemistry, Yale University, P.O. Box 208107, New Haven, Connecticut 06520, United States
| | - Mehmed Z Ertem
- Chemistry Division, Brookhaven National Laboratory, Upton, New York 11973, United States
| | - Mariam Barakat
- Department of Chemistry, American University of Beirut, Beirut 1107 2020, Lebanon
| | - Quinton J Bruch
- Department of Chemistry, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina 27599, United States
| | - Anthony P Deziel
- Department of Chemistry, Yale University, P.O. Box 208107, New Haven, Connecticut 06520, United States
| | - Matthew R Elsby
- Department of Chemistry, Yale University, P.O. Box 208107, New Haven, Connecticut 06520, United States
| | - Faraj Hasanayn
- Department of Chemistry, American University of Beirut, Beirut 1107 2020, Lebanon
| | - Nilay Hazari
- Department of Chemistry, Yale University, P.O. Box 208107, New Haven, Connecticut 06520, United States
| | - Alexander J M Miller
- Department of Chemistry, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina 27599, United States
| | - Matthew V Pecoraro
- Department of Chemistry, Yale University, P.O. Box 208107, New Haven, Connecticut 06520, United States
| | - Allison M Smith
- Department of Chemistry, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina 27599, United States
| | - Nicholas E Smith
- Department of Chemistry, Yale University, P.O. Box 208107, New Haven, Connecticut 06520, United States
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8
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Bose S, Nguyen HD, Ngo AH, Do LH. Fluorescent half-sandwich iridium picolinamidate complexes for in-cell visualization. J Inorg Biochem 2022; 234:111877. [PMID: 35671630 PMCID: PMC9832325 DOI: 10.1016/j.jinorgbio.2022.111877] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/16/2022] [Revised: 05/16/2022] [Accepted: 05/24/2022] [Indexed: 01/13/2023]
Abstract
In this work, we report on the development of fluorescent half-sandwich iridium complexes using a fluorophore attachment strategy. These constructs consist of pentamethylcyclopentadienyl (Cp*) iridium units ligated by picolinamidate donors conjugated to green-emitting boron-dipyrromethene (bodipy) dyes. Reaction studies in H2O/THF mixtures showed that the fluorescent Ir complexes were active as catalysts for transfer hydrogenation, with activities similar to that of their non-fluorescent counterparts. The iridium complexes were taken up by NIH-3T3 mouse fibroblast cells, with 50% inhibition concentrations ranging from ~20-70 μM after exposure for 3 h. Visualization of the bodipy-functionalized Ir complexes in cells using fluorescence microscopy revealed that they were localized in the mitochondria and lysosome but not the nucleus. These results indicate that our fluorescent iridium complexes could be useful for future biological studies requiring intracellular catalyst tracking.
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Affiliation(s)
- Sohini Bose
- Department of Chemistry, University of Houston, Houston, Texas 77004, United States
| | - Hieu D. Nguyen
- Department of Chemistry, University of Houston, Houston, Texas 77004, United States
| | - Anh H. Ngo
- Department of Chemistry, University of Houston, Houston, Texas 77004, United States
| | - Loi H. Do
- Department of Chemistry, University of Houston, Houston, Texas 77004, United States,Corresponding author, (L. H. Do)
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9
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Wang J, Liu C, Cao L, Xiong Y, Ye J, Liu Z, Cheng R. Theoretical investigation of mechanism and ligand effects on half-sandwich iridium complexes for direct reductive amination. MOLECULAR CATALYSIS 2022. [DOI: 10.1016/j.mcat.2021.112050] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/19/2022]
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10
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Tyagi N, Viji M, Ramaiah D. μ-Oxo-bridged iron( iii) complexes for the selective reduction of aromatic ketones catalyzed through base promoted in situ nanoparticle formation. NEW J CHEM 2022. [DOI: 10.1039/d2nj01053d] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Selective TH of aromatic ketones catalyzed by μ-oxo-diiron complexes and in situ NP formation in the presence of a base gave excellent yields (∼99–100%).
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Affiliation(s)
- Nidhi Tyagi
- Photosciences and Photonics, Chemical Sciences and Technology Division, National Institute for Interdisciplinary Science and Technology CSIR, Trivandrum – 695 019, Kerala, India
- Institute of Nano Science and Technology, Knowledge City, Sector-81, Mohali, Punjab – 140306, India
| | - Mambattakkara Viji
- Photosciences and Photonics, Chemical Sciences and Technology Division, National Institute for Interdisciplinary Science and Technology CSIR, Trivandrum – 695 019, Kerala, India
- Academy of Scientific and Innovative Research (AcSIR), CSIR-NIIST Campus, India
| | - Danaboyina Ramaiah
- Photosciences and Photonics, Chemical Sciences and Technology Division, National Institute for Interdisciplinary Science and Technology CSIR, Trivandrum – 695 019, Kerala, India
- Department of Chemistry, Birla Institute of Technology and Science (BITS) Pilani, Hyderabad Campus, India
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11
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Kumah RT, Vijayan P, Ojwach SO. Carboxamide carbonyl-ruthenium(ii) complexes: detailed structural and mechanistic studies in the transfer hydrogenation of ketones. NEW J CHEM 2022. [DOI: 10.1039/d1nj05657c] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/28/2023]
Abstract
The organo-carboxamide carbonyl-ruthenium(ii) complexes displayed moderate catalytic activities in the transfer hydrogenation of a broad spectrum of ketones.
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Affiliation(s)
- Robert T. Kumah
- School of Chemistry and Physics, University of KwaZulu-Natal, Pietermaritzburg Campus, Private Bag X01, Scottsville, Pietermaritzburg 3209, South Africa
| | - Paranthaman Vijayan
- School of Chemistry and Physics, University of KwaZulu-Natal, Pietermaritzburg Campus, Private Bag X01, Scottsville, Pietermaritzburg 3209, South Africa
| | - Stephen O. Ojwach
- School of Chemistry and Physics, University of KwaZulu-Natal, Pietermaritzburg Campus, Private Bag X01, Scottsville, Pietermaritzburg 3209, South Africa
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12
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Yadav S, Vijayan P, Gupta R. Ruthenium complexes of N/O/S based multidentate ligands: Structural diversities and catalysis perspectives. J Organomet Chem 2021. [DOI: 10.1016/j.jorganchem.2021.122081] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
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13
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Stein A, Chen D, Igareta NV, Cotelle Y, Rebelein JG, Ward TR. A Dual Anchoring Strategy for the Directed Evolution of Improved Artificial Transfer Hydrogenases Based on Carbonic Anhydrase. ACS CENTRAL SCIENCE 2021; 7:1874-1884. [PMID: 34849402 PMCID: PMC8620556 DOI: 10.1021/acscentsci.1c00825] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 07/08/2021] [Indexed: 06/13/2023]
Abstract
Artificial metalloenzymes result from anchoring a metal cofactor within a host protein. Such hybrid catalysts combine the selectivity and specificity of enzymes with the versatility of (abiotic) transition metals to catalyze new-to-nature reactions in an evolvable scaffold. With the aim of improving the localization of an arylsulfonamide-bearing iridium-pianostool catalyst within human carbonic anhydrase II (hCAII) for the enantioselective reduction of prochiral imines, we introduced a covalent linkage between the host and the guest. Herein, we show that a judiciously positioned cysteine residue reacts with a p-nitropicolinamide ligand bound to iridium to afford an additional sulfonamide covalent linkage. Three rounds of directed evolution, performed on the dually anchored cofactor, led to improved activity and selectivity for the enantioselective reduction of harmaline (up to 97% ee (R) and >350 turnovers on a preparative scale). To evaluate the substrate scope, the best hits of each generation were tested with eight substrates. X-ray analysis, carried out at various stages of the evolutionary trajectory, was used to scrutinize (i) the nature of the covalent linkage between the cofactor and the host as well as (ii) the remodeling of the substrate-binding pocket.
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Affiliation(s)
- Alina Stein
- Department
of Chemistry, University of Basel, BPR 1096, Mattenstrasse 24a, 4058 Basel, Switzerland
- National
Center of Competence in Research “Molecular Systems Engineering”, 4058 Basel, Switzerland
| | - Dongping Chen
- Department
of Chemistry, University of Basel, BPR 1096, Mattenstrasse 24a, 4058 Basel, Switzerland
- National
Center of Competence in Research “Molecular Systems Engineering”, 4058 Basel, Switzerland
| | - Nico V. Igareta
- Department
of Chemistry, University of Basel, BPR 1096, Mattenstrasse 24a, 4058 Basel, Switzerland
- National
Center of Competence in Research “Molecular Systems Engineering”, 4058 Basel, Switzerland
| | - Yoann Cotelle
- Aix-Marseille
Université, CNRS, Centrale Marseille, iSm2, 13284 Marseille, France
| | - Johannes G. Rebelein
- Max
Planck Institute for Terrestrial Microbiology, Karl-von-Frisch-Strasse 10, D-35043 Marburg, Germany
| | - Thomas R. Ward
- Department
of Chemistry, University of Basel, BPR 1096, Mattenstrasse 24a, 4058 Basel, Switzerland
- National
Center of Competence in Research “Molecular Systems Engineering”, 4058 Basel, Switzerland
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14
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Ramos R, Zimbron JM, Thorimbert S, Chamoreau LM, Munier A, Botuha C, Karaiskou A, Salmain M, Sobczak-Thépot J. Insights into the antiproliferative mechanism of (C^N)-chelated half-sandwich iridium complexes. Dalton Trans 2021; 49:17635-17641. [PMID: 33226042 DOI: 10.1039/d0dt03414b] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022]
Abstract
Transition metal-based anticancer compounds, as an alternative to platinum derivatives, are raising scientific interest as they may present distinct although poorly understood mechanisms of action. We used a structure-activity relationship-based methodology to investigate the chemical and biological features of a series of ten (C^N)-chelated half-sandwich iridiumIII complexes of the general formula [IrCp*(phox)Cl], where (phox) is a 2-phenyloxazoline ligand forming a 5-membered metallacycle. This series of compounds undergoes a fast exchange of their chlorido ligand once solubilised in DMSO. They were cytotoxic to HeLa cells with IC50 values in the micromolar range and induced a rapid activation of caspase-3, an apoptosis marker. In vitro, the oxidative power of all the complexes towards NADH was highlighted but only the complexes bearing substituents on the oxazoline ring were able to produce H2O2 at the micromolar range. However, we demonstrated using a powerful HyPer protein redox sensor-based flow cytometry assay that most complexes rapidly raised intracellular levels of H2O2. Hence, this study shows that oxidative stress can partly explain the cytotoxicity of these complexes on the HeLa cell line and gives a first entry to their mechanism of action.
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Affiliation(s)
- Robin Ramos
- Institut Parisien de Chimie Moléculaire (IPCM), Sorbonne Université, CNRS, 4 place Jussieu, F-75005 Paris, France.
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15
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Abstract
Although the application of arene-osmium(II) complexes in homogeneous catalysis has been much less studied than that of their ruthenium analogues, different works have shown that, in some instances, a comparable or even superior effectiveness can be achieved with this particular class of compounds. This review article focuses on the catalytic applications of arene-osmium(II) complexes. Among others, transfer hydrogenation, hydrogenation, oxidation, and nitrile hydration reactions, as well as different C-C bond forming processes, are comprehensively discussed.
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16
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Mas‐Roselló J, Cope CJ, Tan E, Pinson B, Robinson A, Smejkal T, Cramer N. Iridium‐Catalyzed Acid‐Assisted Hydrogenation of Oximes to Hydroxylamines. Angew Chem Int Ed Engl 2021. [DOI: 10.1002/ange.202103806] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
Affiliation(s)
- Josep Mas‐Roselló
- Laboratory of Asymmetric Catalysis and Synthesis Institute of Chemical Sciences and Engineering Ecole Polytechnique Fédérale de Lausanne (EPFL) Lausanne Switzerland
| | - Christopher J. Cope
- Process Chemistry Research Syngenta Crop Protection AG Schaffhauserstrasse 101 4332 Stein AG Switzerland
| | - Eric Tan
- Process Chemistry Research Syngenta Crop Protection AG Schaffhauserstrasse 101 4332 Stein AG Switzerland
| | - Benjamin Pinson
- Process Chemistry Research Syngenta Crop Protection AG Schaffhauserstrasse 101 4332 Stein AG Switzerland
| | - Alan Robinson
- Process Chemistry Research Syngenta Crop Protection AG Schaffhauserstrasse 101 4332 Stein AG Switzerland
| | - Tomas Smejkal
- Process Chemistry Research Syngenta Crop Protection AG Schaffhauserstrasse 101 4332 Stein AG Switzerland
| | - Nicolai Cramer
- Laboratory of Asymmetric Catalysis and Synthesis Institute of Chemical Sciences and Engineering Ecole Polytechnique Fédérale de Lausanne (EPFL) Lausanne Switzerland
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17
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Mas-Roselló J, Cope CJ, Tan E, Pinson B, Robinson A, Smejkal T, Cramer N. Iridium-Catalyzed Acid-Assisted Hydrogenation of Oximes to Hydroxylamines. Angew Chem Int Ed Engl 2021; 60:15524-15532. [PMID: 33886142 DOI: 10.1002/anie.202103806] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/17/2021] [Indexed: 11/11/2022]
Abstract
We found that cyclometalated cyclopentadienyl iridium(III) complexes are uniquely efficient catalysts in homogeneous hydrogenation of oximes to hydroxylamine products. A stable iridium C,N-chelation is crucial, with alkoxy-substituted aryl ketimine ligands providing the best catalytic performance. Several Ir-complexes were mapped by X-ray crystal analysis in order to collect steric parameters that might guide a rational design of even more active catalysts. A broad range of oximes and oxime ethers were activated with stoichiometric amounts of methanesulfonic acid and reduced at room temperature, remarkably without cleavage of the fragile N-O bond. The exquisite functional group compatibility of our hydrogenation system was further demonstrated by additive tests. Experimental mechanistic investigations support an ionic hydrogenation platform, and suggest a role for the Brønsted acid beyond a proton source. Our studies provide deep understanding of this novel acidic hydrogenation and may facilitate its improvement and application to other challenging substrates.
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Affiliation(s)
- Josep Mas-Roselló
- Laboratory of Asymmetric Catalysis and Synthesis, Institute of Chemical Sciences and Engineering, Ecole Polytechnique Fédérale de Lausanne (EPFL), Lausanne, Switzerland
| | - Christopher J Cope
- Process Chemistry Research, Syngenta Crop Protection AG, Schaffhauserstrasse 101, 4332, Stein, AG, Switzerland
| | - Eric Tan
- Process Chemistry Research, Syngenta Crop Protection AG, Schaffhauserstrasse 101, 4332, Stein, AG, Switzerland
| | - Benjamin Pinson
- Process Chemistry Research, Syngenta Crop Protection AG, Schaffhauserstrasse 101, 4332, Stein, AG, Switzerland
| | - Alan Robinson
- Process Chemistry Research, Syngenta Crop Protection AG, Schaffhauserstrasse 101, 4332, Stein, AG, Switzerland
| | - Tomas Smejkal
- Process Chemistry Research, Syngenta Crop Protection AG, Schaffhauserstrasse 101, 4332, Stein, AG, Switzerland
| | - Nicolai Cramer
- Laboratory of Asymmetric Catalysis and Synthesis, Institute of Chemical Sciences and Engineering, Ecole Polytechnique Fédérale de Lausanne (EPFL), Lausanne, Switzerland
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18
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Nguyen DP, Nguyen HTH, Do LH. Tools and Methods for Investigating Synthetic Metal-Catalyzed Reactions in Living Cells. ACS Catal 2021; 11:5148-5165. [PMID: 34824879 PMCID: PMC8612649 DOI: 10.1021/acscatal.1c00438] [Citation(s) in RCA: 19] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022]
Abstract
Although abiotic catalysts are capable of promoting numerous new-to-nature reactions, only a small subset has so far been successfully integrated into living systems. Research in intracellular catalysis requires an interdisciplinary approach that takes advantage of both chemical and biological tools as well as state-of-the-art instrumentations. In this perspective, we will focus on the techniques that have made studying metal-catalyzed reactions in cells possible using representative examples from the literature. Although the lack of quantitative data in vitro and in vivo has somewhat limited progress in the catalyst development process, recent advances in characterization methods should help overcome some of these deficiencies. Given its tremendous potential, we believe that intracellular catalysis will play a more prominent role in the development of future biotechnologies and therapeutics.
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Affiliation(s)
- Dat P. Nguyen
- Department of Chemistry, University of Houston, 4800 Calhoun Rd, Houston, Texas 77004, United States
| | - Huong T. H. Nguyen
- Department of Chemistry, University of Houston, 4800 Calhoun Rd, Houston, Texas 77004, United States
| | - Loi H. Do
- Department of Chemistry, University of Houston, 4800 Calhoun Rd, Houston, Texas 77004, United States
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19
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Bolitho EM, Coverdale JPC, Bridgewater HE, Clarkson GJ, Quinn PD, Sanchez‐Cano C, Sadler PJ. Tracking Reactions of Asymmetric Organo-Osmium Transfer Hydrogenation Catalysts in Cancer Cells. Angew Chem Int Ed Engl 2021; 60:6462-6472. [PMID: 33590607 PMCID: PMC7985874 DOI: 10.1002/anie.202016456] [Citation(s) in RCA: 15] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/11/2020] [Revised: 01/16/2020] [Indexed: 12/21/2022]
Abstract
Most metallodrugs are prodrugs that can undergo ligand exchange and redox reactions in biological media. Here we have investigated the cellular stability of the anticancer complex [OsII [(η6 -p-cymene)(RR/SS-MePh-DPEN)] [1] (MePh-DPEN=tosyl-diphenylethylenediamine) which catalyses the enantioselective reduction of pyruvate to lactate in cells. The introduction of a bromide tag at an unreactive site on a phenyl substituent of Ph-DPEN allowed us to probe the fate of this ligand and Os in human cancer cells by a combination of X-ray fluorescence (XRF) elemental mapping and inductively coupled plasma-mass spectrometry (ICP-MS). The BrPh-DPEN ligand is readily displaced by reaction with endogenous thiols and translocated to the nucleus, whereas the Os fragment is exported from the cells. These data explain why the efficiency of catalysis is low, and suggests that it could be optimised by developing thiol resistant analogues. Moreover, this work also provides a new way for the delivery of ligands which are inactive when administered on their own.
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Affiliation(s)
- Elizabeth M. Bolitho
- Department of ChemistryUniversity of WarwickCoventryCV4 7ALUK
- I14 Imaging BeamlineDiamond Light SourceOxfordOX11 0DEUK
| | | | | | - Guy J. Clarkson
- Department of ChemistryUniversity of WarwickCoventryCV4 7ALUK
| | - Paul D. Quinn
- I14 Imaging BeamlineDiamond Light SourceOxfordOX11 0DEUK
| | - Carlos Sanchez‐Cano
- Center for Cooperative Research in Biomaterials (CIC biomaGUNE)Basque Research and Technology Alliance (BRTA)Paseo de Miramon 18220014San SebastiánSpain
| | - Peter J. Sadler
- Department of ChemistryUniversity of WarwickCoventryCV4 7ALUK
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20
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Bolitho EM, Coverdale JPC, Bridgewater HE, Clarkson GJ, Quinn PD, Sanchez‐Cano C, Sadler PJ. Tracking Reactions of Asymmetric Organo‐Osmium Transfer Hydrogenation Catalysts in Cancer Cells. Angew Chem Int Ed Engl 2021. [DOI: 10.1002/ange.202016456] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Affiliation(s)
- Elizabeth M. Bolitho
- Department of Chemistry University of Warwick Coventry CV4 7AL UK
- I14 Imaging Beamline Diamond Light Source Oxford OX11 0DE UK
| | | | | | - Guy J. Clarkson
- Department of Chemistry University of Warwick Coventry CV4 7AL UK
| | - Paul D. Quinn
- I14 Imaging Beamline Diamond Light Source Oxford OX11 0DE UK
| | - Carlos Sanchez‐Cano
- Center for Cooperative Research in Biomaterials (CIC biomaGUNE) Basque Research and Technology Alliance (BRTA) Paseo de Miramon 182 20014 San Sebastián Spain
| | - Peter J. Sadler
- Department of Chemistry University of Warwick Coventry CV4 7AL UK
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21
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Nguyen HTH, Do LH. Organoiridium-quinone conjugates for facile hydrogen peroxide generation. Chem Commun (Camb) 2020; 56:13381-13384. [PMID: 33034316 PMCID: PMC7642182 DOI: 10.1039/d0cc04970k] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022]
Abstract
An organoiridium complex bearing a quinone moiety was shown to significantly accelerate the rate of H2O2 formation in the presence of air and sodium formate at low catalyst concentrations. This reaction is proposed to operate through a synergistic mechanism involving transfer hydrogenation catalysis and radical chemistry. Our bifunctional iridium complex could potentially be used in anti-cancer chemotherapy or other applications requiring rapid generation of reactive oxygen species.
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Affiliation(s)
- Huong T H Nguyen
- Department of Chemistry, University of Houston, 4800 Calhoun Road, Houston, TX 77204, USA.
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22
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Nguyen DP, Sladek RN, Do LH. Scope and Limitations of Reductive Amination Catalyzed by Half-Sandwich Iridium Complexes Under Mild Reaction Conditions. Tetrahedron Lett 2020; 61. [PMID: 32728300 DOI: 10.1016/j.tetlet.2020.152196] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
The conversion of aldehydes and ketones to 1° amines could be promoted by half-sandwich iridium complexes using ammonium formate as both the nitrogen and hydride source. To optimize this method for green chemical synthesis, we tested various carbonyl substrates in common polar solvents at physiological temperature (37 °C) and ambient pressure. We found that in methanol, excellent selectivity for the amine over alcohol/amide products could be achieved for a broad assortment of carbonyl-containing compounds. In aqueous media, selective reduction of carbonyls to 1° amines was achieved in the absence of acids. Unfortunately, at Ir catalyst concentrations of <1 mM in water, reductive amination efficiency dropped significantly, which suggest that this catalytic methodology might be not suitable for aqueous applications where very low catalyst concentration is required (e.g., inside living cells).
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Affiliation(s)
- Dat P Nguyen
- Department of Chemistry, University of Houston, Houston, Texas 77004, United States
| | - Rudolph N Sladek
- Department of Chemistry, University of Houston, Houston, Texas 77004, United States
| | - Loi H Do
- Department of Chemistry, University of Houston, Houston, Texas 77004, United States
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23
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Zhang WY, Banerjee S, Hughes GM, Bridgewater HE, Song JI, Breeze BG, Clarkson GJ, Coverdale JPC, Sanchez-Cano C, Ponte F, Sicilia E, Sadler PJ. Ligand-centred redox activation of inert organoiridium anticancer catalysts. Chem Sci 2020; 11:5466-5480. [PMID: 34094073 PMCID: PMC8159363 DOI: 10.1039/d0sc00897d] [Citation(s) in RCA: 31] [Impact Index Per Article: 7.8] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/15/2020] [Accepted: 04/21/2020] [Indexed: 12/14/2022] Open
Abstract
Organometallic complexes with novel activation mechanisms are attractive anticancer drug candidates. Here, we show that half-sandwich iodido cyclopentadienyl iridium(iii) azopyridine complexes exhibit potent antiproliferative activity towards cancer cells, in most cases more potent than cisplatin. Despite their inertness towards aquation, these iodido complexes can undergo redox activation by attack of the abundant intracellular tripeptide glutathione (GSH) on the chelated azopyridine ligand to generate paramagnetic intermediates, and hydroxyl radicals, together with thiolate-bridged dinuclear iridium complexes, and liberate reduced hydrazopyridine ligand. DFT calculations provided insight into the mechanism of this activation. GS- attack on the azo bond facilitates the substitution of iodide by GS-, and leads to formation of GSSG and superoxide if O2 is present as an electron-acceptor, in a largely exergonic pathway. Reactions of these iodido complexes with GSH generate Ir-SG complexes, which are catalysts for GSH oxidation. The complexes promoted elevated levels of reactive oxygen species (ROS) in human lung cancer cells. This remarkable ligand-centred activation mechanism coupled to redox reactions adds a new dimension to the design of organoiridium anticancer prodrugs.
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Affiliation(s)
- Wen-Ying Zhang
- Department of Chemistry, University of Warwick Coventry CV4 7AL UK
| | - Samya Banerjee
- Department of Chemistry, University of Warwick Coventry CV4 7AL UK
| | - George M Hughes
- Department of Chemistry, University of Warwick Coventry CV4 7AL UK
| | | | - Ji-Inn Song
- Department of Chemistry, University of Warwick Coventry CV4 7AL UK
| | - Ben G Breeze
- Spectroscopy Research Technology Platform, University of Warwick Coventry CV4 7AL UK
| | - Guy J Clarkson
- Department of Chemistry, University of Warwick Coventry CV4 7AL UK
| | | | | | - Fortuna Ponte
- Department of Chemistry and Chemical Technologies, University of Calabria via Pietro Bucci 87036 Arcavacata di Rende Cs Italy
| | - Emilia Sicilia
- Department of Chemistry and Chemical Technologies, University of Calabria via Pietro Bucci 87036 Arcavacata di Rende Cs Italy
| | - Peter J Sadler
- Department of Chemistry, University of Warwick Coventry CV4 7AL UK
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Brereton KR, Smith NE, Hazari N, Miller AJM. Thermodynamic and kinetic hydricity of transition metal hydrides. Chem Soc Rev 2020; 49:7929-7948. [DOI: 10.1039/d0cs00405g] [Citation(s) in RCA: 29] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
This review of thermodynamic and kinetic hydricity provides conceptual overviews, tutorials on how to determine hydricity both experimentally and computationally, and salient case studies.
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Affiliation(s)
| | | | - Nilay Hazari
- Department of Chemistry
- Yale University
- New Haven
- USA
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