1
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Roy S, Wang Y, Zhao X, Dayananda T, Chu JM, Zhang Y, Fasan R. Stereodivergent Synthesis of Pyridyl Cyclopropanes via Enzymatic Activation of Pyridotriazoles. J Am Chem Soc 2024; 146:19673-19679. [PMID: 39008121 DOI: 10.1021/jacs.4c06103] [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: 07/16/2024]
Abstract
Hemoproteins have recently emerged as powerful biocatalysts for new-to-nature carbene transfer reactions. Despite this progress, these strategies have remained largely limited to diazo-based carbene precursor reagents. Here, we report the development of a biocatalytic strategy for the stereoselective construction of pyridine-functionalized cyclopropanes via the hemoprotein-mediated activation of pyridotriazoles (PyTz) as stable and readily accessible carbene sources. This method enables the asymmetric cyclopropanation of a variety of olefins, including electron-rich and electrodeficient ones, with high activity, high stereoselectivity, and enantiodivergent selectivity, providing access to mono- and diarylcyclopropanes that incorporate a pyridine moiety and thus two structural motifs of high value in medicinal chemistry. Mechanistic studies reveal a multifaceted role of 7-halogen substitution in the pyridotriazole reagent toward favoring multiple catalytic steps in the transformation. This work provides the first example of asymmetric olefin cyclopropanation with pyridotriazoles, paving the way to the exploitation of these attractive and versatile reagents for enzyme-catalyzed carbene-mediated reactions.
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Affiliation(s)
- Satyajit Roy
- Department of Chemistry and Biochemistry, University of Texas at Dallas, 800 W. Campbell Road, Richardson, Texas 75080, United States
| | - Yining Wang
- Department of Chemistry and Biochemistry, University of Texas at Dallas, 800 W. Campbell Road, Richardson, Texas 75080, United States
| | - Xinyi Zhao
- Department of Chemistry and Chemical Biology, Stevens Institute of Technology, 1 Castle Point Terrace, Hoboken, New Jersey 07030, United States
| | - Thakshila Dayananda
- Department of Chemistry, University of Rochester, 120 Trustee Road, Rochester, New York 14627, United States
| | - Jia-Min Chu
- Department of Chemistry and Chemical Biology, Stevens Institute of Technology, 1 Castle Point Terrace, Hoboken, New Jersey 07030, United States
| | - Yong Zhang
- Department of Chemistry and Chemical Biology, Stevens Institute of Technology, 1 Castle Point Terrace, Hoboken, New Jersey 07030, United States
| | - Rudi Fasan
- Department of Chemistry and Biochemistry, University of Texas at Dallas, 800 W. Campbell Road, Richardson, Texas 75080, United States
- Department of Chemistry, University of Rochester, 120 Trustee Road, Rochester, New York 14627, United States
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2
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Chaturvedi SS, Vargas S, Ajmera P, Alexandrova AN. Directed Evolution of Protoglobin Optimizes the Enzyme Electric Field. J Am Chem Soc 2024. [PMID: 38848547 DOI: 10.1021/jacs.4c03914] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/09/2024]
Abstract
To unravel why computational design fails in creating viable enzymes, while directed evolution (DE) succeeds, our research delves into the laboratory evolution of protoglobin. DE has adapted this protein to efficiently catalyze carbene transfer reactions. We show that the previously proposed enhanced substrate access and binding alone cannot account for increased yields during DE. The 3D electric field in the entire active site is tracked through protein dynamics, clustered using the affinity propagation algorithm, and subjected to principal component analysis. This analysis reveals notable changes in the electric field with DE, where distinct field topologies influence transition state energetics and mechanism. A chemically meaningful field component emerges and takes the lead during DE and facilitates crossing the barrier to carbene transfer. Our findings underscore intrinsic electric field dynamic's influence on enzyme function, the ability of the field to switch mechanisms within the same protein, and the crucial role of the field in enzyme design.
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Affiliation(s)
- Shobhit S Chaturvedi
- Department of Chemistry and Biochemistry, University of California, Los Angeles, California 90095, United States
| | - Santiago Vargas
- Department of Chemistry and Biochemistry, University of California, Los Angeles, California 90095, United States
| | - Pujan Ajmera
- Department of Chemistry and Biochemistry, University of California, Los Angeles, California 90095, United States
| | - Anastassia N Alexandrova
- Department of Chemistry and Biochemistry, University of California, Los Angeles, California 90095, United States
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3
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Nam D, Bacik JP, Khade RL, Aguilera MC, Wei Y, Villada JD, Neidig ML, Zhang Y, Ando N, Fasan R. Mechanistic manifold in a hemoprotein-catalyzed cyclopropanation reaction with diazoketone. Nat Commun 2023; 14:7985. [PMID: 38042860 PMCID: PMC10693563 DOI: 10.1038/s41467-023-43559-7] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/21/2023] [Accepted: 11/14/2023] [Indexed: 12/04/2023] Open
Abstract
Hemoproteins have recently emerged as promising biocatalysts for new-to-nature carbene transfer reactions. However, mechanistic understanding of the interplay between productive and unproductive pathways in these processes is limited. Using spectroscopic, structural, and computational methods, we investigate the mechanism of a myoglobin-catalyzed cyclopropanation reaction with diazoketones. These studies shed light on the nature and kinetics of key catalytic steps in this reaction, including the formation of an early heme-bound diazo complex intermediate, the rate-determining nature of carbene formation, and the cyclopropanation mechanism. Our analyses further reveal the existence of a complex mechanistic manifold for this reaction that includes a competing pathway resulting in the formation of an N-bound carbene adduct of the heme cofactor, which was isolated and characterized by X-ray crystallography, UV-Vis, and Mössbauer spectroscopy. This species can regenerate the active biocatalyst, constituting a non-productive, yet non-destructive detour from the main catalytic cycle. These findings offer a valuable framework for both mechanistic analysis and design of hemoprotein-catalyzed carbene transfer reactions.
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Affiliation(s)
- Donggeon Nam
- Department of Chemistry, University of Rochester, Rochester, NY, 14627, USA
| | - John-Paul Bacik
- Department of Chemistry and Chemical Biology, Cornell University, Ithaca, NY, 14853, USA
| | - Rahul L Khade
- Department of Chemistry and Chemical Biology, Stevens Institute of Technology, Hoboken, NJ, 07030, USA
| | | | - Yang Wei
- Department of Chemistry and Chemical Biology, Stevens Institute of Technology, Hoboken, NJ, 07030, USA
| | - Juan D Villada
- Department of Chemistry, University of Rochester, Rochester, NY, 14627, USA
- Department of Chemistry and Biochemistry, University of Texas at Dallas, Richardson, TX, 75080, USA
| | - Michael L Neidig
- Inorganic Chemistry Laboratory, Department of Chemistry, University of Oxford, South Parks Road, Oxford, OX1 3QR, UK.
| | - Yong Zhang
- Department of Chemistry and Chemical Biology, Stevens Institute of Technology, Hoboken, NJ, 07030, USA.
| | - Nozomi Ando
- Department of Chemistry and Chemical Biology, Cornell University, Ithaca, NY, 14853, USA.
| | - Rudi Fasan
- Department of Chemistry, University of Rochester, Rochester, NY, 14627, USA.
- Department of Chemistry and Biochemistry, University of Texas at Dallas, Richardson, TX, 75080, USA.
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4
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Zhang Y, Chu JM. Computational Mechanistic Investigations of Biocatalytic Nitrenoid C-H Functionalizations via Engineered Heme Proteins. Chembiochem 2023; 24:e202300260. [PMID: 37134298 DOI: 10.1002/cbic.202300260] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/31/2023] [Revised: 05/01/2023] [Accepted: 05/03/2023] [Indexed: 05/05/2023]
Abstract
Engineered heme proteins were developed to possess numerous excellent biocatalytic nitrenoid C-H functionalizations. Computational approaches such as density functional theory (DFT), hybrid quantum mechanics/molecular mechanics (QM/MM), and molecular dynamics (MD) calculations were employed to help understand some important mechanistic aspects of these heme nitrene transfer reactions. This review summarizes advances of computational reaction pathway results of these biocatalytic intramolecular and intermolecular C-H aminations/amidations, focusing on mechanistic origins of reactivity, regioselectivity, enantioselectivity, diastereoselectivity as well as effects of substrate substituent, axial ligand, metal center, and protein environment. Some important common and distinctive mechanistic features of these reactions were also described with brief outlook of future development.
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Affiliation(s)
- Yong Zhang
- Department of Chemistry and Chemical Biology, Stevens Institute of Technology, 1 Castle Point Terrace, Hoboken, NJ 07030, USA
| | - Jia-Min Chu
- Department of Chemistry and Chemical Biology, Stevens Institute of Technology, 1 Castle Point Terrace, Hoboken, NJ 07030, USA
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5
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Chatterjee R, Jindal G. Role of mutations in a chemoenzymatic enantiodivergent C(sp 3)-H insertion: exploring the mechanism and origin of stereoselectivity. Chem Sci 2023; 14:8810-8822. [PMID: 37621422 PMCID: PMC10445471 DOI: 10.1039/d3sc02788k] [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: 06/01/2023] [Accepted: 07/23/2023] [Indexed: 08/26/2023] Open
Abstract
New-to-nature enzymes have emerged as powerful catalysts in recent years for streamlining various stereoselective organic transformations. While synthetic strategies employing engineered enzymes have witnessed proliferating success, there is limited clarity on the mechanistic front and more so when considering molecular-level insights into the role of selected mutations, dramatically escalating catalytic competency and selectivity. We have investigated the mechanism and correlation between mutations and exquisite stereoselectivity of a lactone carbene insertion into the C(sp3)-H bond of substituted aniline, catalyzed by two mutants of a cytochrome P450 variant, "P411" (engineered through directed evolution) in which the axial cysteine has been mutated to serine, utilizing various computational tools. The pivotal role of S264 and L/R328 mutations in the active site has been delineated computationally using two cluster models, thus rationalizing the enantiodivergence. This report provides much-needed insights into the origin of enantiodivergence, furnishing a mechanistic framework for understanding the anchoring effects of H-bond donor residues with the lactone ring. This study is expected to have important implications in the rational design of stereodivergent enzymes and toward successful in silico enzyme designing.
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Affiliation(s)
- Ritwika Chatterjee
- Department of Organic Chemistry, Chemical Sciences Division, Indian Institute of Science Bangalore 560012 India
| | - Garima Jindal
- Department of Organic Chemistry, Chemical Sciences Division, Indian Institute of Science Bangalore 560012 India
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6
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Huang S, Deng WH, Liao RZ, He C. Repurposing a Nitric Oxide Transport Hemoprotein Nitrophorin 2 for Olefin Cyclopropanation. ACS Catal 2022. [DOI: 10.1021/acscatal.2c03515] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Affiliation(s)
- Shunzhi Huang
- School of Chemistry and Chemical Engineering, South China University of Technology, 510640 Guangzhou, China
| | - Wen-Hao Deng
- School of Chemistry and Chemical Engineering, Huazhong University of Science and Technology, 430074 Wuhan, China
| | - Rong-Zhen Liao
- School of Chemistry and Chemical Engineering, Huazhong University of Science and Technology, 430074 Wuhan, China
| | - Chunmao He
- School of Chemistry and Chemical Engineering, South China University of Technology, 510640 Guangzhou, China
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7
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Wei Y, Conklin M, Zhang Y. Biocatalytic Intramolecular C-H aminations via Engineered Heme Proteins: Full Reaction Pathways and Axial Ligand Effects. Chemistry 2022; 28:e202202006. [PMID: 35840505 PMCID: PMC9804930 DOI: 10.1002/chem.202202006] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/28/2022] [Indexed: 01/09/2023]
Abstract
Engineered heme protein biocatalysts provide an efficient and sustainable approach to develop amine-containing compounds through C-H amination. A quantum chemical study to reveal the complete heme catalyzed intramolecular C-H amination pathway and protein axial ligand effect was reported, using reactions of an experimentally used arylsulfonylazide with hemes containing L=none, SH- , MeO- , and MeOH to simulate no axial ligand, negatively charged Cys and Ser ligands, and a neutral ligand for comparison. Nitrene formation was found as the overall rate-determining step (RDS) and the catalyst with Ser ligand has the best reactivity, consistent with experimental reports. Both RDS and non-RDS (nitrene transfer) transition states follow the barrier trend of MeO-
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Affiliation(s)
- Yang Wei
- Department of Chemistry and Chemical BiologyStevens Institute of Technology1 Castle Point on HudsonHobokenNJ 07030USA
- Department of Chemistry and BiochemistryLoyola University Chicago1032 W Sheridan RdChicagoIL 60660USA
| | - Melissa Conklin
- Department of Chemistry and Chemical BiologyStevens Institute of Technology1 Castle Point on HudsonHobokenNJ 07030USA
| | - Yong Zhang
- Department of Chemistry and Chemical BiologyStevens Institute of Technology1 Castle Point on HudsonHobokenNJ 07030USA
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8
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He Y, Huang Z, Wu K, Ma J, Zhou YG, Yu Z. Recent advances in transition-metal-catalyzed carbene insertion to C-H bonds. Chem Soc Rev 2022; 51:2759-2852. [PMID: 35297455 DOI: 10.1039/d1cs00895a] [Citation(s) in RCA: 82] [Impact Index Per Article: 41.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/29/2023]
Abstract
C-H functionalization has been emerging as a powerful method to establish carbon-carbon and carbon-heteroatom bonds. Many efforts have been devoted to transition-metal-catalyzed direct transformations of C-H bonds. Metal carbenes generated in situ from transition-metal compounds and diazo or its equivalents are usually applied as the transient reactive intermediates to furnish a catalytic cycle for new C-C and C-X bond formation. Using this strategy compounds from unactivated simple alkanes to complex molecules can be further functionalized or transformed to multi-functionalized compounds. In this area, transition-metal-catalyzed carbene insertion to C-H bonds has been paid continuous attention. Diverse catalyst design strategies, synthetic methods, and potential applications have been developed. This critical review will summarize the advance in transition-metal-catalyzed carbene insertion to C-H bonds dated up to July 2021, by the categories of C-H bonds from aliphatic C(sp3)-H, aryl (aromatic) C(sp2)-H, heteroaryl (heteroaromatic) C(sp2)-H bonds, alkenyl C(sp2)-H, and alkynyl C(sp)-H, as well as asymmetric carbene insertion to C-H bonds, and more coverage will be given to the recent work. Due to the rapid development of the C-H functionalization area, future directions in this topic are also discussed. This review will give the authors an overview of carbene insertion chemistry in C-H functionalization with focus on the catalytic systems and synthetic applications in C-C bond formation.
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Affiliation(s)
- Yuan He
- Dalian Institute of Chemical Physics, Chinese Academy of Sciences, 457 Zhongshan Road, Dalian 116023, P. R. China. .,University of Chinese Academy of Sciences, Beijing 100049, P. R. China
| | - Zilong Huang
- Dalian Institute of Chemical Physics, Chinese Academy of Sciences, 457 Zhongshan Road, Dalian 116023, P. R. China. .,University of Chinese Academy of Sciences, Beijing 100049, P. R. China
| | - Kaikai Wu
- Dalian Institute of Chemical Physics, Chinese Academy of Sciences, 457 Zhongshan Road, Dalian 116023, P. R. China.
| | - Juan Ma
- Dalian Institute of Chemical Physics, Chinese Academy of Sciences, 457 Zhongshan Road, Dalian 116023, P. R. China. .,University of Chinese Academy of Sciences, Beijing 100049, P. R. China
| | - Yong-Gui Zhou
- Dalian Institute of Chemical Physics, Chinese Academy of Sciences, 457 Zhongshan Road, Dalian 116023, P. R. China.
| | - Zhengkun Yu
- Dalian Institute of Chemical Physics, Chinese Academy of Sciences, 457 Zhongshan Road, Dalian 116023, P. R. China. .,State Key Laboratory of Organometallic Chemistry, Shanghai Institute of Organic Chemistry, Chinese Academy of Sciences, 354 Fenglin Road, Shanghai 200032, P. R. China.,Innovation Academy for Green Manufacture, Chinese Academy of Sciences, Beijing 100190, P. R. China
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9
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Wang Z, Cheng J, Ding W, Wang D. C(sp3)–H Amination Catalyzed by Ir(Me)-Porphyrin: A Computational Study. Organometallics 2022. [DOI: 10.1021/acs.organomet.1c00668] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/11/2023]
Affiliation(s)
- Zihao Wang
- Key Laboratory of Theoretical and Computational Photochemistry, Ministry of Education, College of Chemistry, Beijing Normal University, Beijing 100875, China
| | - Junhui Cheng
- Key Laboratory of Theoretical and Computational Photochemistry, Ministry of Education, College of Chemistry, Beijing Normal University, Beijing 100875, China
| | - Wanjian Ding
- Key Laboratory of Theoretical and Computational Photochemistry, Ministry of Education, College of Chemistry, Beijing Normal University, Beijing 100875, China
| | - Dongqi Wang
- State Key Laboratory of Fine Chemicals, Liaoning Key Laboratory for Catalytic Conversion of Carbon Resources, School of Chemical Engineering, Dalian University of Technology, Dalian 116024, China
- Multidisciplinary Initiative Center, CAS-HKU Joint Laboratory of Metallomics on Health and Environment, Institute of High Energy Physics, Chinese Academy of Sciences, Beijing 100049, China
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10
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Garcia-Borràs M, Kan SBJ, Lewis RD, Tang A, Jimenez-Osés G, Arnold FH, Houk KN. Origin and Control of Chemoselectivity in Cytochrome c Catalyzed Carbene Transfer into Si-H and N-H bonds. J Am Chem Soc 2021; 143:7114-7123. [PMID: 33909977 DOI: 10.1021/jacs.1c02146] [Citation(s) in RCA: 21] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
A cytochrome c heme protein was recently engineered to catalyze the formation of carbon-silicon bonds via carbene insertion into Si-H bonds, a reaction that was not previously known to be catalyzed by a protein. High chemoselectivity toward C-Si bond formation over competing C-N bond formation was achieved, although this trait was not screened for during directed evolution. Using computational and experimental tools, we now establish that activity and chemoselectivity are modulated by conformational dynamics of a protein loop that covers the substrate access to the iron-carbene active species. Mutagenesis of residues computationally predicted to control the loop conformation altered the protein's chemoselectivity from preferred silylation to preferred amination of a substrate containing both N-H and Si-H functionalities. We demonstrate that information on protein structure and conformational dynamics, combined with knowledge of mechanism, leads to understanding of how non-natural and selective chemical transformations can be introduced into the biological world.
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Affiliation(s)
- Marc Garcia-Borràs
- Department of Chemistry and Biochemistry, University of California, Los Angeles, California 90095, United States.,Institut de Química Computacional i Catàlisi (IQCC) and Departament de Química, Universitat de Girona, Carrer Maria Aurèlia Capmany 69, 17003 Girona, Spain
| | - S B Jennifer Kan
- Division of Chemistry and Chemical Engineering 210-41, California Institute of Technology, 1200 East California Boulevard, Pasadena, California 91125, United States
| | - Russell D Lewis
- Division of Biology and Bioengineering, California Institute of Technology, 1200 East California Boulevard, Pasadena, California 91125, United States
| | - Allison Tang
- Division of Chemistry and Chemical Engineering 210-41, California Institute of Technology, 1200 East California Boulevard, Pasadena, California 91125, United States
| | | | - Frances H Arnold
- Division of Biology and Bioengineering, California Institute of Technology, 1200 East California Boulevard, Pasadena, California 91125, United States.,Division of Chemistry and Chemical Engineering 210-41, California Institute of Technology, 1200 East California Boulevard, Pasadena, California 91125, United States
| | - K N Houk
- Department of Chemistry and Biochemistry, University of California, Los Angeles, California 90095, United States
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11
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Balhara R, Chatterjee R, Jindal G. A computational approach to understand the role of metals and axial ligands in artificial heme enzyme catalyzed C-H insertion. Phys Chem Chem Phys 2021; 23:9500-9511. [PMID: 33885085 DOI: 10.1039/d1cp00412c] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/25/2023]
Abstract
Engineered heme enzymes such as myoglobin and cytochrome P450s metalloproteins are gaining widespread importance due to their efficiency in catalyzing non-natural reactions. In a recent strategy, the naturally occurring Fe metal in the heme unit was replaced with non-native metals such as Ir, Rh, Co, Cu, etc., and axial ligands to generate artificial metalloenzymes. Determining the best metal-ligand for a chemical transformation is not a trivial task. Here we demonstrate how computational approaches can be used in deciding the best metal-ligand combination which would be highly beneficial in designing new enzymes as well as small molecule catalysts. We have used Density Functional Theory (DFT) to shed light on the enhanced reactivity of an Ir system with varying axial ligands. We look at the insertion of a carbene group generated from diazo precursors via N2 extrusion into a C-H bond. For both Ir(Me) and Fe systems, the first step, i.e., N2 extrusion is the rate determining step. Strikingly, neither the better ligand overlap with 5d orbitals on Ir nor the electrophilicity on the carbene centre play a significant role. A comparison of Fe and Ir systems reveals that a lower distortion in the Ir(Me)-porphyrin on moving from the reactant to the transition state renders it catalytically more active. We notice that for both metal porphyrins, the free energy barriers are affected by axial ligand substitution. Further, for Fe porphyrin, the axial ligand also changes the preferred spin state. We show that for the carbene insertion into the C-H bond, Fe porphyrin systems undergo a stepwise HAT (hydrogen atom transfer) instead of a concerted hydride transfer process. Importantly, we find that the substitution of the axial Me ligand on Ir to imidazole or chloride, or without an axial substitution changes the rate determining step of the reaction. Therefore, an optimum ligand that can balance the barriers for both steps of the catalytic cycle is essential. We subsequently used the QM cluster approach to delineate the protein environment's role and mutations in improving the catalytic activity of the Ir(Me) system.
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Affiliation(s)
- Reena Balhara
- Department of Organic Chemistry, Indian Institute of Science, Bangalore 560012, India.
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12
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Abucayon EG, Chu JM, Ayala M, Khade RL, Zhang Y, Richter-Addo GB. Insight into the preferential N-binding versus O-binding of nitrosoarenes to ferrous and ferric heme centers. Dalton Trans 2021; 50:3487-3498. [PMID: 33634802 PMCID: PMC8061117 DOI: 10.1039/d0dt03604h] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Nitrosoarenes (ArNOs) are toxic metabolic intermediates that bind to heme proteins to inhibit their functions. Although much of their biological functions involve coordination to the Fe centers of hemes, the factors that determine N-binding or O-binding of these ArNOs have not been determined. We utilize X-ray crystallography and density functional theory (DFT) analyses of new representative ferrous and ferric ArNO compounds to provide the first theoretical insight into preferential N-binding versus O-binding of ArNOs to hemes. Our X-ray structural results favored N-binding of ArNO to ferrous heme centers, and O-binding to ferric hemes. Results of the DFT calculations rationalize this preferential binding on the basis of the energies of associated spin-states, and reveal that the dominant stabilization forces in the observed ferrous N-coordination and ferric O-coordination are dπ-pπ* and dσ-pπ*, respectively. Our results provide, for the first time, an explanation why in situ oxidation of the ferrous-ArNO compound to its ferric state results in the observed subsequent dissociation of the ligand.
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Affiliation(s)
- Erwin G Abucayon
- Department of Chemistry and Biochemistry, University of Oklahoma, 101 Stephenson Parkway, Norman, OK 73019, USA.
| | - Jia-Min Chu
- Department of Chemistry and Chemical Biology, Stevens Institute of Technology, Castle Point on Hudson, Hoboken, NJ 07030, USA.
| | - Megan Ayala
- Department of Chemistry and Biochemistry, University of Oklahoma, 101 Stephenson Parkway, Norman, OK 73019, USA.
| | - Rahul L Khade
- Department of Chemistry and Chemical Biology, Stevens Institute of Technology, Castle Point on Hudson, Hoboken, NJ 07030, USA.
| | - Yong Zhang
- Department of Chemistry and Chemical Biology, Stevens Institute of Technology, Castle Point on Hudson, Hoboken, NJ 07030, USA.
| | - George B Richter-Addo
- Department of Chemistry and Biochemistry, University of Oklahoma, 101 Stephenson Parkway, Norman, OK 73019, USA.
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13
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Casali E, Gallo E, Toma L. An In-Depth Computational Study of Alkene Cyclopropanation Catalyzed by Fe(porphyrin)(OCH 3) Complexes. The Environmental Effects on the Energy Barriers. Inorg Chem 2020; 59:11329-11336. [PMID: 32799510 PMCID: PMC8009515 DOI: 10.1021/acs.inorgchem.0c00912] [Citation(s) in RCA: 12] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
Iron porphyrin methoxy complexes, of the general formula [Fe(porphyrin)(OCH3)], are able to catalyze the reaction of diazo compounds with alkenes to give cyclopropane products with very high efficiency and selectivity. The overall mechanism of these reactions was thoroughly investigated with the aid of a computational approach based on density functional theory calculations. The energy profile for the processes catalyzed by the oxidized [FeIII(Por)(OCH3)] (Por = porphine) as well as the reduced [FeII(Por)(OCH3)]- forms of the iron porphyrin was determined. The main reaction step is the same in both of the cases, that is, the one leading to the terminal-carbene intermediate [Fe(Por)(OCH3)(CHCO2Et)] with simultaneous dinitrogen loss; however, the reduced species performs much better than the oxidized one. Contrarily to the iron(III) profile in which the carbene intermediate is directly obtained from the starting reactant complex, the favored iron(II) process is more intricate. The initially formed reactant adduct between [FeII(Por)(OCH3)]- and ethyl diazoacetate (EDA) is converted into a closer reactant adduct, which is in turn converted into the terminal iron porphyrin carbene [Fe(Por)(OCH3)(CHCO2Et)]-. The two corresponding transition states are almost isoenergetic, thus raising the question of whether the rate-determining step corresponds to dinitrogen loss or to the previous structural and electronic rearrangement. The ethylene addition to the terminal carbene is a downhill process, which, on the open-shell singlet surface, presents a defined but probably short-living diradicaloid intermediate, though other spin-state surfaces do not show this intermediate allowing a direct access to the cyclopropane product. For the crucial stationary points, the more complex catalyst [Fe(2)(OCH3)], in which a sterically hindered chiral bulk is mounted onto the porphyrin, was investigated. The corresponding computational data disclose the very significant effect of the porphyrin skeleton on the reaction energy profile. Though the geometrical features around the reactive core of the system remain unchanged, the energy barriers become much lower, thus revealing the profound effects that can be exerted by the three-dimensional organic scaffold surrounding the reaction site.
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Affiliation(s)
- Emanuele Casali
- Dipartimento di Chimica, Università di Pavia, Via Taramelli 12, 27100 Pavia, Italy
| | - Emma Gallo
- Dipartimento di Chimica, Università di Milano, Via Golgi 19, 20133 Milano, Italy
| | - Lucio Toma
- Dipartimento di Chimica, Università di Pavia, Via Taramelli 12, 27100 Pavia, Italy
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14
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Affiliation(s)
- Vasco F. Batista
- LAQV-REQUIMTE and Department of Chemistry, University of Aveiro, Campus de Santiago, 3810-193, Aveiro, Portugal
| | - Diana C. G. A. Pinto
- LAQV-REQUIMTE and Department of Chemistry, University of Aveiro, Campus de Santiago, 3810-193, Aveiro, Portugal
| | - Artur M. S. Silva
- LAQV-REQUIMTE and Department of Chemistry, University of Aveiro, Campus de Santiago, 3810-193, Aveiro, Portugal
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15
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Empel C, Jana S, Koenigs RM. C-H Functionalization via Iron-Catalyzed Carbene-Transfer Reactions. Molecules 2020; 25:molecules25040880. [PMID: 32079259 PMCID: PMC7070285 DOI: 10.3390/molecules25040880] [Citation(s) in RCA: 25] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/04/2020] [Revised: 02/04/2020] [Accepted: 02/05/2020] [Indexed: 12/17/2022] Open
Abstract
The direct C-H functionalization reaction is one of the most efficient strategies by which to introduce new functional groups into small organic molecules. Over time, iron complexes have emerged as versatile catalysts for carbine-transfer reactions with diazoalkanes under mild and sustainable reaction conditions. In this review, we discuss the advances that have been made using iron catalysts to perform C-H functionalization reactions with diazoalkanes. We give an overview of early examples employing stoichiometric iron carbene complexes and continue with recent advances in the C-H functionalization of C(sp2)-H and C(sp3)-H bonds, concluding with the latest developments in enzymatic C-H functionalization reactions using iron-heme-containing enzymes.
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16
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Li X, Dong L, Liu Y. Theoretical Study of Iron Porphyrin Nitrene: Formation Mechanism, Electronic Nature, and Intermolecular C–H Amination. Inorg Chem 2020; 59:1622-1632. [DOI: 10.1021/acs.inorgchem.9b02216] [Citation(s) in RCA: 16] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Affiliation(s)
- Xinyi Li
- School of Chemistry and Chemical Engineering, Shandong University, Jinan, Shandong 250100, China
| | - Lihua Dong
- School of Chemistry and Chemical Engineering, Qilu Normal University, Jinan, Shandong 250013, China
| | - Yongjun Liu
- School of Chemistry and Chemical Engineering, Shandong University, Jinan, Shandong 250100, China
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17
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Damiano C, Sonzini P, Gallo E. Iron catalysts with N-ligands for carbene transfer of diazo reagents. Chem Soc Rev 2020; 49:4867-4905. [DOI: 10.1039/d0cs00221f] [Citation(s) in RCA: 44] [Impact Index Per Article: 11.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
This review provides an overview of the catalytic activity of iron complexes of nitrogen ligands in driving carbene transfers towards CC, C–H and X–H bonds. The reactivity of diazo reagents is discussed as well as the proposed reaction mechanisms.
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Affiliation(s)
| | - Paolo Sonzini
- Department of Chemistry
- University of Milan
- 20133 Milan
- Italy
| | - Emma Gallo
- Department of Chemistry
- University of Milan
- 20133 Milan
- Italy
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18
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Liu Y, You T, Wang HX, Tang Z, Zhou CY, Che CM. Iron- and cobalt-catalyzed C(sp3)–H bond functionalization reactions and their application in organic synthesis. Chem Soc Rev 2020; 49:5310-5358. [DOI: 10.1039/d0cs00340a] [Citation(s) in RCA: 62] [Impact Index Per Article: 15.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Abstract
This review highlights the developments in iron and cobalt catalyzed C(sp3)–H bond functionalization reactions with emphasis on their applications in organic synthesis, i.e. natural products and pharmaceuticals synthesis and/or modification.
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Affiliation(s)
- Yungen Liu
- Department of Chemistry
- Southern University of Science and Technology
- Shenzhen
- P. R. China
| | - Tingjie You
- Department of Chemistry
- State Key Laboratory of Synthetic Chemistry
- The University of Hong Kong
- Hong Kong
- P. R. China
| | - Hai-Xu Wang
- Department of Chemistry
- State Key Laboratory of Synthetic Chemistry
- The University of Hong Kong
- Hong Kong
- P. R. China
| | - Zhou Tang
- Department of Chemistry
- State Key Laboratory of Synthetic Chemistry
- The University of Hong Kong
- Hong Kong
- P. R. China
| | - Cong-Ying Zhou
- Department of Chemistry
- State Key Laboratory of Synthetic Chemistry
- The University of Hong Kong
- Hong Kong
- P. R. China
| | - Chi-Ming Che
- Department of Chemistry
- Southern University of Science and Technology
- Shenzhen
- P. R. China
- Department of Chemistry
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19
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Cailler LP, Clémancey M, Barilone J, Maldivi P, Latour JM, Sorokin AB. Comparative Study of the Electronic Structures of μ-Oxo, μ-Nitrido, and μ-Carbido Diiron Octapropylporphyrazine Complexes and Their Catalytic Activity in Cyclopropanation of Olefins. Inorg Chem 2019; 59:1104-1116. [DOI: 10.1021/acs.inorgchem.9b02718] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Affiliation(s)
- Lucie P. Cailler
- Institut de Recherches sur la Catalyse et l’Environnement de Lyon IRCELYON, UMR 5256, CNRS - Université Lyon 1, 2 avenue A. Einstein, 69626 Villeurbanne cedex, France
| | - Martin Clémancey
- Univ. Grenoble-Alpes, CEA, CNRS, IRIG-SyMMES, Grenoble 38000, France
| | - Jessica Barilone
- Univ. Grenoble-Alpes, CEA, CNRS, IRIG, CBM, Grenoble 38000, France
- Univ. Grenoble-Alpes, CEA, CNRS, IRIG-SyMMES, Grenoble 38000, France
| | - Pascale Maldivi
- Univ. Grenoble-Alpes, CEA, CNRS, IRIG, CBM, Grenoble 38000, France
| | - Jean-Marc Latour
- Univ. Grenoble-Alpes, CEA, CNRS, IRIG-SyMMES, Grenoble 38000, France
| | - Alexander B. Sorokin
- Institut de Recherches sur la Catalyse et l’Environnement de Lyon IRCELYON, UMR 5256, CNRS - Université Lyon 1, 2 avenue A. Einstein, 69626 Villeurbanne cedex, France
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20
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Abstract
On the occasion of Professor Frances H. Arnold's recent acceptance of the 2018 Nobel Prize in Chemistry, we honor her numerous contributions to the fields of directed evolution and biocatalysis. Arnold pioneered the development of directed evolution methods for engineering enzymes as biocatalysts. Her highly interdisciplinary research has provided a ground not only for understanding the mechanisms of enzyme evolution but also for developing commercially viable enzyme biocatalysts and biocatalytic processes. In this Account, we highlight some of her notable contributions in the past three decades in the development of foundational directed evolution methods and their applications in the design and engineering of enzymes with desired functions for biocatalysis. Her work has created a paradigm shift in the broad catalysis field.
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Affiliation(s)
- Rudi Fasan
- Department of Chemistry, University of Rochester, Rochester, New York 14627, United States
| | - S. B. Jennifer Kan
- Division of Chemistry and Chemical Engineering, California Institute of Technology, Pasadena, California 91125, United States
| | - Huimin Zhao
- Departments of Chemical and Biomolecular Engineering, Chemistry, and Biochemistry, Carl R. Woese Institute for Genomic Biology, University of Illinois at Urbana−Champaign, Urbana, Illinois 61801, United States
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21
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Zhang Y. Computational Investigations of Heme Carbenes and Heme Carbene Transfer Reactions. Chemistry 2019; 25:13231-13247. [DOI: 10.1002/chem.201901984] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/30/2019] [Revised: 06/19/2019] [Indexed: 12/15/2022]
Affiliation(s)
- Yong Zhang
- Department of Chemistry and Chemical Biology Stevens Institute of Technology 1 Castle Point on Hudson Hoboken NJ 07030 USA
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22
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Davethu PA, de Visser SP. CO2 Reduction on an Iron-Porphyrin Center: A Computational Study. J Phys Chem A 2019; 123:6527-6535. [DOI: 10.1021/acs.jpca.9b05102] [Citation(s) in RCA: 29] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022]
Affiliation(s)
- Paul A. Davethu
- The Manchester Institute of Biotechnology and School of Chemical Engineering and Analytical Science, the University of Manchester, 131 Princess Street, Manchester M1 7DN, United Kingdom
| | - Sam P. de Visser
- The Manchester Institute of Biotechnology and School of Chemical Engineering and Analytical Science, the University of Manchester, 131 Princess Street, Manchester M1 7DN, United Kingdom
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23
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Khade RL, Chandgude AL, Fasan R, Zhang Y. Mechanistic Investigation of Biocatalytic Heme Carbenoid Si-H Insertions. ChemCatChem 2019; 11:3101-3108. [PMID: 31428208 PMCID: PMC6699785 DOI: 10.1002/cctc.201801755] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/29/2018] [Indexed: 12/28/2022]
Abstract
Recent studies reported the development of biocatalytic heme carbenoid Si-H insertions for the selective formation of carbon-silicon bonds, but many mechanistic questions remain unaddressed. To this end, a DFT mechanistic investigation was performed which reveals an FeII-based concerted hydride transfer mechanism with early transition state feature. The results from these computational analyses are consistent with experimental data of radical trapping, kinetic isotope effects, and structure-reactivity data using engineered variants of hemoproteins. Detailed geometric and electronic profiles along the heme catalyzed Si-H insertion pathways were provided to help understand the origin of experimental reactivity trends. Quantitative relationships between reaction barriers and some properties such as charge transfer from substrate to heme carbene and Si-H bond length change from reactant to transition state were found. Results suggest catalyst modifications to facilitate the charge transfer from the silane substrate to the carbene, which was determined to be a major electronic driving force of this reaction, should enable the development of improved biocatalysts for Si-H carbene insertion reactions.
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Affiliation(s)
- Rahul L Khade
- Department of Chemistry and Chemical Biology, Stevens Institute of Technology, 1 Castle Point on Hudson, Hoboken, NJ 07030 (USA)
| | - Ajay L Chandgude
- Department of Chemistry, University of Rochester, 120 Trustee Road, Rochester, NY 14627 (USA)
| | - Rudi Fasan
- Department of Chemistry, University of Rochester, 120 Trustee Road, Rochester, NY 14627 (USA)
| | - Yong Zhang
- Department of Chemistry and Chemical Biology, Stevens Institute of Technology, 1 Castle Point on Hudson, Hoboken, NJ 07030 (USA)
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24
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Tinoco A, Wei Y, Bacik JP, Carminati DM, Moore EJ, Ando N, Zhang Y, Fasan R. Origin of high stereocontrol in olefin cyclopropanation catalyzed by an engineered carbene transferase. ACS Catal 2019; 9:1514-1524. [PMID: 31134138 DOI: 10.1021/acscatal.8b04073] [Citation(s) in RCA: 39] [Impact Index Per Article: 7.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022]
Abstract
Recent advances in metalloprotein engineering have led to the development of a myoglobin-based catalyst, Mb(H64V,V68A), capable of promoting the cyclopropanation of vinylarenes with high efficiency and high diastereo- and enantioselectivity. Whereas many enzymes evolved in nature often exhibit catalytic proficiency and exquisite stereoselectivity, how these features are achieved for a non-natural reaction has remained unclear. In this work, the structural determinants responsible for chiral induction and high stereocontrol in Mb(H64V,V68A)-catalyzed cyclopropanation were investigated via a combination of crystallographic, computational (DFT), and structure-activity analyses. Our results show the importance of steric complementarity and non-covalent interactions involving first-sphere active site residues, heme-carbene, and the olefin substrate, in dictating the stereochemical outcome of the cyclopropanation reaction. High stereocontrol is achieved through two major mechanisms. First, by enforcing a specific conformation of the heme-bound carbene within the active site. Second, by controlling the geometry of attack of the olefin on the carbene via steric occlusion, attractive van der Waals forces and protein-mediated π-π interactions with the olefin substrate. These insights could be leveraged to expand the substrate scope of the myoglobin-based cyclopropanation catalyst toward non-activated olefins and to increase its cyclopropanation activity in the presence of a bulky α-diazo-ester. This work sheds first light into the origin of enzyme-catalyzed enantioselective cyclopropanation, furnishing a mechanistic framework for both understanding the reactivity of current systems and guiding the future development of biological catalysts for this class of synthetically important, abiotic transformations.
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Affiliation(s)
- Antonio Tinoco
- Department of Chemistry, University of Rochester, Rochester, New York 14627, United States
| | - Yang Wei
- Department of Chemistry and Chemical Biology, Stevens Institute of Technology, Hoboken, New Jersey 07030, United States
| | - John-Paul Bacik
- Department of Chemistry, Princeton University, Princeton, New Jersey 08544, United States
| | - Daniela M. Carminati
- Department of Chemistry, University of Rochester, Rochester, New York 14627, United States
| | - Eric J. Moore
- Department of Chemistry, University of Rochester, Rochester, New York 14627, United States
| | - Nozomi Ando
- Department of Chemistry, Princeton University, Princeton, New Jersey 08544, United States
| | - Yong Zhang
- Department of Chemistry and Chemical Biology, Stevens Institute of Technology, Hoboken, New Jersey 07030, United States
| | - Rudi Fasan
- Department of Chemistry, University of Rochester, Rochester, New York 14627, United States
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25
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Herndon JW. The chemistry of the carbon-transition metal double and triple bond: Annual survey covering the year 2017. Coord Chem Rev 2018. [DOI: 10.1016/j.ccr.2018.08.007] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
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26
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Zhang RK, Huang X, Arnold FH. Selective CH bond functionalization with engineered heme proteins: new tools to generate complexity. Curr Opin Chem Biol 2018; 49:67-75. [PMID: 30343008 DOI: 10.1016/j.cbpa.2018.10.004] [Citation(s) in RCA: 98] [Impact Index Per Article: 16.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/08/2018] [Revised: 09/27/2018] [Accepted: 10/02/2018] [Indexed: 12/13/2022]
Abstract
CH functionalization is an attractive strategy to construct and diversify molecules. Heme proteins, predominantly cytochromes P450, are responsible for an array of CH oxidations in biology. Recent work has coupled concepts from synthetic chemistry, computation, and natural product biosynthesis to engineer heme protein systems to deliver products with tailored oxidation patterns. Heme protein catalysis has been shown to go well beyond these native reactions and now accesses new-to-nature CH transformations, including CN and CC bond forming processes. Emerging work with these systems moves us along the ambitious path of building complexity from the ubiquitous CH bond.
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Affiliation(s)
- Ruijie K Zhang
- Division of Chemistry and Chemical Engineering, California Institute of Technology, 1200 East California Boulevard, MC 210-41, Pasadena, CA 91125, United States
| | - Xiongyi Huang
- Division of Chemistry and Chemical Engineering, California Institute of Technology, 1200 East California Boulevard, MC 210-41, Pasadena, CA 91125, United States
| | - Frances H Arnold
- Division of Chemistry and Chemical Engineering, California Institute of Technology, 1200 East California Boulevard, MC 210-41, Pasadena, CA 91125, United States.
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27
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Su H, Ma G, Liu Y. Theoretical Insights into the Mechanism and Stereoselectivity of Olefin Cyclopropanation Catalyzed by Two Engineered Cytochrome P450 Enzymes. Inorg Chem 2018; 57:11738-11745. [DOI: 10.1021/acs.inorgchem.8b01875] [Citation(s) in RCA: 21] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Hao Su
- Key Lab of Colloid and Interface Chemistry, Ministry of Education, School of Chemistry and Chemical Engineering, Shandong University, Jinan, Shandong 250100, China
| | - Guangcai Ma
- Key Lab of Colloid and Interface Chemistry, Ministry of Education, School of Chemistry and Chemical Engineering, Shandong University, Jinan, Shandong 250100, China
- College of Geography and Environmental Sciences, Zhejiang Normal University, Jinhua, Zhejiang 321004, China
| | - Yongjun Liu
- Key Lab of Colloid and Interface Chemistry, Ministry of Education, School of Chemistry and Chemical Engineering, Shandong University, Jinan, Shandong 250100, China
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28
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Lewis RD, Garcia-Borràs M, Chalkley MJ, Buller AR, Houk KN, Kan SBJ, Arnold FH. Catalytic iron-carbene intermediate revealed in a cytochrome c carbene transferase. Proc Natl Acad Sci U S A 2018; 115:7308-7313. [PMID: 29946033 PMCID: PMC6048479 DOI: 10.1073/pnas.1807027115] [Citation(s) in RCA: 84] [Impact Index Per Article: 14.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
Recently, heme proteins have been discovered and engineered by directed evolution to catalyze chemical transformations that are biochemically unprecedented. Many of these nonnatural enzyme-catalyzed reactions are assumed to proceed through a catalytic iron porphyrin carbene (IPC) intermediate, although this intermediate has never been observed in a protein. Using crystallographic, spectroscopic, and computational methods, we have captured and studied a catalytic IPC intermediate in the active site of an enzyme derived from thermostable Rhodothermus marinus (Rma) cytochrome c High-resolution crystal structures and computational methods reveal how directed evolution created an active site for carbene transfer in an electron transfer protein and how the laboratory-evolved enzyme achieves perfect carbene transfer stereoselectivity by holding the catalytic IPC in a single orientation. We also discovered that the IPC in Rma cytochrome c has a singlet ground electronic state and that the protein environment uses geometrical constraints and noncovalent interactions to influence different IPC electronic states. This information helps us to understand the impressive reactivity and selectivity of carbene transfer enzymes and offers insights that will guide and inspire future engineering efforts.
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Affiliation(s)
- Russell D Lewis
- Division of Biology and Bioengineering, California Institute of Technology, Pasadena, CA 91125
| | - Marc Garcia-Borràs
- Department of Chemistry and Biochemistry, University of California, Los Angeles, CA 90095
| | - Matthew J Chalkley
- Division of Chemistry and Chemical Engineering, California Institute of Technology, Pasadena, CA 91125
| | - Andrew R Buller
- Division of Chemistry and Chemical Engineering, California Institute of Technology, Pasadena, CA 91125
| | - K N Houk
- Department of Chemistry and Biochemistry, University of California, Los Angeles, CA 90095;
| | - S B Jennifer Kan
- Division of Chemistry and Chemical Engineering, California Institute of Technology, Pasadena, CA 91125
| | - Frances H Arnold
- Division of Biology and Bioengineering, California Institute of Technology, Pasadena, CA 91125;
- Division of Chemistry and Chemical Engineering, California Institute of Technology, Pasadena, CA 91125
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29
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de Brito Sá E, Rimola A, Rodríguez-Santiago L, Sodupe M, Solans-Monfort X. Reactivity of Metal Carbenes with Olefins: Theoretical Insights on the Carbene Electronic Structure and Cyclopropanation Reaction Mechanism. J Phys Chem A 2018; 122:1702-1712. [DOI: 10.1021/acs.jpca.7b11656] [Citation(s) in RCA: 21] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- E. de Brito Sá
- Departament
de Química, Universitat Autònoma de Barcelona, 08193 Bellaterra, Spain
- Universidade Federal do Piauí, Campus Ministro Reis Velloso, 64202-020 Parnaíba, Piauí, Brazil
| | - A. Rimola
- Departament
de Química, Universitat Autònoma de Barcelona, 08193 Bellaterra, Spain
| | | | - M. Sodupe
- Departament
de Química, Universitat Autònoma de Barcelona, 08193 Bellaterra, Spain
| | - X. Solans-Monfort
- Departament
de Química, Universitat Autònoma de Barcelona, 08193 Bellaterra, Spain
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30
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Wei Y, Tinoco A, Steck V, Fasan R, Zhang Y. Cyclopropanations via Heme Carbenes: Basic Mechanism and Effects of Carbene Substituent, Protein Axial Ligand, and Porphyrin Substitution. J Am Chem Soc 2018; 140:1649-1662. [PMID: 29268614 PMCID: PMC5875692 DOI: 10.1021/jacs.7b09171] [Citation(s) in RCA: 94] [Impact Index Per Article: 15.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Abstract
![]()
Catalytic carbene
transfer to olefins is a useful approach to synthesize
cyclopropanes, which are key structural motifs in many drugs and biologically
active natural products. While catalytic methods for olefin cyclopropanation
have largely relied on rare transition-metal-based catalysts, recent
studies have demonstrated the promise and synthetic value of iron-based
heme-containing proteins for promoting these reactions with excellent
catalytic activity and selectivity. Despite this progress, the mechanism
of iron-porphyrin and hemoprotein-catalyzed olefin cyclopropanation
has remained largely unknown. Using a combination of quantum chemical
calculations and experimental mechanistic analyses, the present study
shows for the first time that the increasingly useful C=C functionalizations
mediated by heme carbenes feature an FeII-based, nonradical,
concerted nonsynchronous mechanism, with early transition state character.
This mechanism differs from the FeIV-based, radical, stepwise
mechanism of heme-dependent monooxygenases. Furthermore, the effects
of the carbene substituent, metal coordinating axial ligand, and porphyrin
substituent on the reactivity of the heme carbenes was systematically
investigated, providing a basis for explaining experimental reactivity
results and defining strategies for future catalyst development. Our
results especially suggest the potential value of electron-deficient
porphyrin ligands for increasing the electrophilicity and thus the
reactivity of the heme carbene. Metal-free reactions were also studied
to reveal temperature and carbene substituent effects on catalytic
vs noncatalytic reactions. This study sheds new light into the mechanism
of iron-porphyrin and hemoprotein-catalyzed cyclopropanation reactions
and it is expected to facilitate future efforts toward sustainable
carbene transfer catalysis using these systems.
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Affiliation(s)
- Yang Wei
- Department of Chemistry and Chemical Biology, Stevens Institute of Technology , 1 Castle Point on Hudson, Hoboken, New Jersey 07030, United States of America
| | - Antonio Tinoco
- Department of Chemistry, University of Rochester , 120 Trustee Road, Rochester, New York 14627, United States of America
| | - Viktoria Steck
- Department of Chemistry, University of Rochester , 120 Trustee Road, Rochester, New York 14627, United States of America
| | - Rudi Fasan
- Department of Chemistry, University of Rochester , 120 Trustee Road, Rochester, New York 14627, United States of America
| | - Yong Zhang
- Department of Chemistry and Chemical Biology, Stevens Institute of Technology , 1 Castle Point on Hudson, Hoboken, New Jersey 07030, United States of America
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