1
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Jiao Z, Jaunich KT, Tao T, Gottschall O, Hughes MM, Turlik A, Schuppe A. Unified Approach to Deamination and Deoxygenation Through Isonitrile Hydrodecyanation: A Combined Experimental and Computational Investigation. Angew Chem Int Ed Engl 2024:e202405779. [PMID: 38619535 DOI: 10.1002/anie.202405779] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/25/2024] [Revised: 04/13/2024] [Accepted: 04/15/2024] [Indexed: 04/16/2024]
Abstract
Herein, we describe a general hydrodefunctionalization protocol of alcohols and amines through a common isonitrile intermediate. To cleave the relatively inert C-NC bond, we leveraged dual hydrogen atom transfer (HAT) and photoredox catalysis to generate a nucleophilic boryl radical, which readily forms an imidoyl radical intermediate from the isonitrile. Rapid β-scission then accomplishes defunctionalization. This method has been applied to the hydrodefunctionalization of both amine and alcohol-containing pharmaceuticals, natural products, and biomolecules. We extended this approach to the reduction of carbonyls and olefins to their saturated counterparts, as well as the hydrodecyanation of alkyl nitriles. Both experimental and computational studies demonstrate a facile β-scission of the imidoyl radical, and reconcile differences in reactivity between nitriles and isonitriles within our protocol.
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Affiliation(s)
- Ziqi Jiao
- VANDERBILT UNIVERSITY, Department of Chemistry, UNITED STATES
| | - Kyle T Jaunich
- VANDERBILT UNIVERSITY, Department of Chemistry, UNITED STATES
| | - Thomas Tao
- Skidmore College, Department of Chemistry, UNITED STATES
| | | | | | - Aneta Turlik
- Skidmore College, Department of Chemistry, UNITED STATES
| | - Alexander Schuppe
- Vanderbilt University, Department of Chemistry, 1234 Stevenson Center Ln., 7330 Stevenson Center, 37240, Nashville, UNITED STATES
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2
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Lyu H, Tugwell TH, Chen Z, Kukier GA, Turlik A, Wu Y, Houk KN, Liu P, Dong G. Modular synthesis of 1,2-azaborines via ring-opening BN-isostere benzannulation. Nat Chem 2024; 16:269-276. [PMID: 37783725 DOI: 10.1038/s41557-023-01343-6] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/10/2022] [Accepted: 09/08/2023] [Indexed: 10/04/2023]
Abstract
1,2-Azaborines represent a unique class of benzene isosteres that have attracted interest for developing pharmaceuticals with better potency and bioavailability. However, it remains a long-standing challenge to prepare monocyclic 1,2-azaborines, particularly multi-substituted ones, in an efficient and modular manner. Here we report a straightforward method to directly access diverse multi-substituted 1,2-azaborines from readily available cyclopropyl imines/ketones and dibromoboranes under relatively mild conditions. The reaction is scalable, shows a broad substrate scope, and tolerates a range of functional groups. The utility of this method is demonstrated in the concise syntheses of BN isosteres of a PD-1/PD-L1 inhibitor and pyrethroid insecticide, bifenthrin. Combined experimental and computational mechanistic studies suggest that the reaction pathway involves boron-mediated cyclopropane ring-opening and base-mediated elimination, followed by an unusual low-barrier 6π-electrocyclization accelerated by the BN/CC isomerism. This method is anticipated to find applications for the synthesis of BN-isostere analogues in medicinal chemistry, and the mechanistic insights gained here may guide developing other boron-mediated electrocyclizations.
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Affiliation(s)
- Hairong Lyu
- Department of Chemistry, University of Chicago, Chicago, IL, USA
| | - Thomas H Tugwell
- Department of Chemistry, University of Pittsburgh, Pittsburgh, PA, USA
| | - Zhijie Chen
- Department of Chemistry, University of Chicago, Chicago, IL, USA
| | - Garrett A Kukier
- Department of Chemistry and Biochemistry, University of California, Los Angeles, CA, USA
| | - Aneta Turlik
- Department of Chemistry and Biochemistry, University of California, Los Angeles, CA, USA
| | - Yifei Wu
- Department of Chemistry, University of Chicago, Chicago, IL, USA
| | - K N Houk
- Department of Chemistry and Biochemistry, University of California, Los Angeles, CA, USA.
| | - Peng Liu
- Department of Chemistry, University of Pittsburgh, Pittsburgh, PA, USA.
| | - Guangbin Dong
- Department of Chemistry, University of Chicago, Chicago, IL, USA.
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3
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Goyal K, Kukier GA, Chen X, Turlik A, Houk KN, Sarpong R. Rearrangement of a carboxy-substituted spiro[4.4]nonatriene to annulated fulvenes through a Pd(ii)-mediated 1,5-vinyl shift. Chem Sci 2023; 14:11809-11817. [PMID: 37920349 PMCID: PMC10619539 DOI: 10.1039/d3sc03222a] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/23/2023] [Accepted: 09/19/2023] [Indexed: 11/04/2023] Open
Abstract
A novel synthesis of aryl-substituted, enantioenriched fulvenes from an oxidative Heck cascade and rearrangement of a carboxy-substituted spiro[4.4]nonatriene is disclosed. Mechanistic investigations with density functional theory (DFT) calculations and empirical results support the net transformation occurring through a novel Pd(ii)-mediated 1,5-vinyl shift from a vinyl-palladium intermediate that terminates with protodepalladation. This spiro-to-fused bicycle conversion tolerates a range of electron-rich and deficient arylboronic acids to give a range of mono- and diaryl substituted annulated fulvenes in moderate to good yields and enantiomeric ratios. Overall, this work connects two classes of molecules with a rich history in physical organic chemistry.
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Affiliation(s)
- Karan Goyal
- Department of Chemistry, University of California Berkeley CA 94720 USA
| | - Garrett A Kukier
- Department of Chemistry and Biochemistry, University of California Los Angeles CA 90095 USA
| | - Xiangyang Chen
- Department of Chemistry and Biochemistry, University of California Los Angeles CA 90095 USA
| | - Aneta Turlik
- Department of Chemistry and Biochemistry, University of California Los Angeles CA 90095 USA
| | - K N Houk
- Department of Chemistry and Biochemistry, University of California Los Angeles CA 90095 USA
| | - Richmond Sarpong
- Department of Chemistry, University of California Berkeley CA 94720 USA
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4
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Alcock E, Mackey P, Turlik A, Bhatt K, Light ME, Houk KN, McGlacken GP. The Aldol-Tishchenko Reaction of Butanone, Cyclobutanone and a 3-Pentanone Derived Sulfinylimine and DFT Calculations of the Stereo-determining Step. Chemistry 2023; 29:e202203029. [PMID: 36617506 DOI: 10.1002/chem.202203029] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/28/2022] [Revised: 12/12/2022] [Accepted: 12/20/2022] [Indexed: 01/10/2023]
Abstract
Herein, we present a highly diastereoselective method to furnish acyclic 3-amino-1,5-diol derivatives using a tandem double-aldol-Tishchenko protocol (dr up to >99 : 1) using a butanone derived sulfinylimine. In most cases only 1 diastereomer predominates, from a possible 16. The reaction is also regioselective. In addition, the highly challenging cyclobutanone and 3-pentanone derivatives are also amenable to a double-aldol-Tishchenko reaction, although the dr values are modest. Despite that, clean single diastereomers can be isolated, which should prove very useful in medicinal chemistry and other areas. Detailed DFT calculations support the observed stereoselectivities in all cases, providing a rationale for the excellent dr values in the butanone series and the moderate values for the 3-pentanone class.
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Affiliation(s)
- Emma Alcock
- School of Chemistry and Analytical and Biological Research Facility, University College Cork, T12 YN60, Cork, Ireland
| | - Pamela Mackey
- School of Chemistry and Analytical and Biological Research Facility, University College Cork, T12 YN60, Cork, Ireland
| | - Aneta Turlik
- Department of Chemistry and Biochemistry, University of California, Los Angeles, California, 90095-1596, USA
| | - Khushi Bhatt
- Department of Chemistry and Biochemistry, University of California, Los Angeles, California, 90095-1596, USA
| | - Mark E Light
- University of Southampton, Chemistry Department University Road, Southampton, SO17 1BJ, UK
| | - Kendall N Houk
- Department of Chemistry and Biochemistry, University of California, Los Angeles, California, 90095-1596, USA
| | - Gerard P McGlacken
- School of Chemistry and Analytical and Biological Research Facility, University College Cork, T12 YN60, Cork, Ireland
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5
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Abstract
(+)-Matrine and (+)-isomatrine are tetracyclic alkaloids isolated from the plant Sophora flavescens, the roots of which are used in traditional Chinese medicine. Biosynthetically, these alkaloids are proposed to derive from three molecules of (-)-lysine via the intermediacy of the unstable cyclic imine Δ1-piperidine. Inspired by the biosynthesis, a new dearomative annulation reaction has been developed that leverages pyridine as a stable surrogate for Δ1-piperidine. In this key transformation, two molecules of pyridine are joined with a molecule of glutaryl chloride to give the complete tetracyclic framework of the matrine alkaloids in a single step. Using this dearomative annulation, isomatrine is synthesized in four steps from inexpensive commercially available chemicals. Isomatrine then serves as the precursor to additional lupin alkaloids, including matrine, allomatrine, isosophoridine, and sophoridine.
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Affiliation(s)
- Jeff K. Kerkovius
- Division of Chemistry and Chemical Engineering, California Institute of Technology, Pasadena, CA 91125, USA
| | - Andrea Stegner
- Division of Chemistry and Chemical Engineering, California Institute of Technology, Pasadena, CA 91125, USA
| | - Aneta Turlik
- Departmentof Chemistry and Biochemistry University of California, Los Angeles, Los Angeles, CA 90095, USA
| | - Pik Hoi Lam
- Division of Chemistry and Chemical Engineering, California Institute of Technology, Pasadena, CA 91125, USA
| | - Kendall N. Houk
- Departmentof Chemistry and Biochemistry University of California, Los Angeles, Los Angeles, CA 90095, USA
| | - Sarah E. Reisman
- Division of Chemistry and Chemical Engineering, California Institute of Technology, Pasadena, CA 91125, USA
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6
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Wu X, Turlik A, Luan B, He F, Qu J, Houk KN, Chen Y. Nickel-Catalyzed Enantioselective Reductive Alkyl-Carbamoylation of Internal Alkenes. Angew Chem Int Ed Engl 2022; 61:e202207536. [PMID: 35818326 PMCID: PMC9427719 DOI: 10.1002/anie.202207536] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/22/2022] [Indexed: 12/16/2022]
Abstract
Herein, we leverage the Ni-catalyzed enantioselective reductive dicarbofunctionalization of internal alkenes with alkyl iodides to enable the synthesis of chiral pyrrolidinones bearing vicinal stereogenic centers. The application of newly developed 1-Nap Quinim is critical for formation of two contiguous stereocenters in high yield, enantioselectivity, and diastereoselectivity. This catalytic system also improves both the yield and enantioselectivity in the synthesis of α,α-dialkylated γ-lactams. Computational studies reveal that the enantiodetermining step proceeds with a carbamoyl-NiI intermediate that is reduced by the Mn reductant prior to intramolecular migratory insertion. The presence of the t-butyl group of the Quinim ligand leads to an unfavorable distortion of the substrate in the TS that leads to the minor enantiomer. Calculations also support an improvement in enantioselectivity with 1-Nap Quinim compared to p-tol Quinim.
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Affiliation(s)
- Xianqing Wu
- Key Laboratory for Advanced Materials and Joint International Research Laboratory of Precision Chemistry and Molecular Engineering, Feringa Nobel Prize Scientist Joint Research Center, Frontiers Science Center for Materiobiology and Dynamic Chemistry, School of Chemistry and Molecular Engineering, East China University of Science & Technology, Shanghai, 200237, China
| | - Aneta Turlik
- Department of Chemistry and Biochemistry, University of California, Los Angeles
| | - Baixue Luan
- Key Laboratory for Advanced Materials and Joint International Research Laboratory of Precision Chemistry and Molecular Engineering, Feringa Nobel Prize Scientist Joint Research Center, Frontiers Science Center for Materiobiology and Dynamic Chemistry, School of Chemistry and Molecular Engineering, East China University of Science & Technology, Shanghai, 200237, China
| | - Feng He
- Key Laboratory for Advanced Materials and Joint International Research Laboratory of Precision Chemistry and Molecular Engineering, Feringa Nobel Prize Scientist Joint Research Center, Frontiers Science Center for Materiobiology and Dynamic Chemistry, School of Chemistry and Molecular Engineering, East China University of Science & Technology, Shanghai, 200237, China
| | - Jingping Qu
- Key Laboratory for Advanced Materials and Joint International Research Laboratory of Precision Chemistry and Molecular Engineering, Feringa Nobel Prize Scientist Joint Research Center, Frontiers Science Center for Materiobiology and Dynamic Chemistry, School of Chemistry and Molecular Engineering, East China University of Science & Technology, Shanghai, 200237, China
| | - K. N. Houk
- Department of Chemistry and Biochemistry, University of California, Los Angeles
| | - Yifeng Chen
- Key Laboratory for Advanced Materials and Joint International Research Laboratory of Precision Chemistry and Molecular Engineering, Feringa Nobel Prize Scientist Joint Research Center, Frontiers Science Center for Materiobiology and Dynamic Chemistry, School of Chemistry and Molecular Engineering, East China University of Science & Technology, Shanghai, 200237, China
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7
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Wu X, Turlik A, Luan B, He F, Qu J, Houk KN, Chen Y. Nickel‐Catalyzed Enantioselective Reductive Alkyl‐Carbamoylation of Internal Alkenes. Angew Chem Int Ed Engl 2022. [DOI: 10.1002/ange.202207536] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Affiliation(s)
- Xianqing Wu
- East China University of Science and Technology school of chemistry and molecular engeering CHINA
| | - Aneta Turlik
- UCLA: University of California Los Angeles Department of Chemistry and Biochemistry UNITED STATES
| | - Baixue Luan
- East China University of Science and Technology school of chemistry and molecular engineering CHINA
| | - Feng He
- East China University of Science and Technology school of chemistry and molecular engeering CHINA
| | - Jingping Qu
- East China University of Science and Technology school of chemistry and molecular engineering CHINA
| | - Kendall N. Houk
- University of California, Los Angeles 607 Charles E Young Drive East 90095 Los Angeles UNITED STATES
| | - Yifeng Chen
- East China University of Science and Technology School of Chemistry and Molecular Engineering 130 Meilong Road 200237 Shanghai CHINA
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8
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Espinoza RV, Maskeri MA, Turlik A, Nangia A, Khatri Y, Montgomery J, Houk KN, Sherman DH. Epoxidation and Late-Stage C–H Functionalization by P450 TamI Are Mediated by Variant Heme-Iron Oxidizing Species. ACS Catal 2022. [DOI: 10.1021/acscatal.2c00364] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Affiliation(s)
| | - Mark A. Maskeri
- Department of Chemistry and Biochemistry, University of California, Los Angeles, California 90095, United States
| | - Aneta Turlik
- Department of Chemistry and Biochemistry, University of California, Los Angeles, California 90095, United States
| | - Anjanay Nangia
- Department of Chemistry, Emory University, Atlanta, Georgia 30322, United States
| | | | | | - K. N. Houk
- Department of Chemistry and Biochemistry, University of California, Los Angeles, California 90095, United States
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9
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Urner LM, Lee GY, Treacy JW, Turlik A, Khan SI, Houk KN, Jung ME. Intramolecular N-H⋅⋅⋅F Hydrogen Bonding Interaction in a Series of 4-Anilino-5-Fluoroquinazolines: Experimental and Theoretical Characterization of Electronic and Conformational Effects. Chemistry 2022; 28:e202103135. [PMID: 34767667 PMCID: PMC9482468 DOI: 10.1002/chem.202103135] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/03/2021] [Indexed: 01/12/2023]
Abstract
The 4-anilino-6,7-ethylenedioxy-5-fluoroquinazoline scaffold is presented as a novel model system for the characterization of the weak NH⋅⋅⋅F hydrogen bonding (HB) interaction. In this scaffold, the aniline NH proton is forced into close proximity with the nearby fluorine (dH,F ∼2.0 Å, ∠∼138°), and a through-space interaction is observed by NMR spectroscopy with couplings (1h JNH,F ) of 19±1 Hz. A combination of experimental (NMR spectroscopy and X-ray crystallography) and theoretical methods (DFT calculations) were used for the characterization of this weak interaction. In particular, the effects of conformational rigidity and steric compression on coupling were investigated. This scaffold was used for the direct comparison of fluoride with methoxy as HB acceptors, and the susceptibility of the NH⋅⋅⋅F interaction to changes in electron distribution and resonance was probed by preparing a series of molecules with different electron-donating or -withdrawing groups in the positions para to the NH and F. The results support the idea that fluorine can act as a weak HB acceptor, and the HB strength can be modulated through additive and linear electronic substituent effects.
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Affiliation(s)
- Lorenz M. Urner
- Department of Chemistry and Biochemistry, University of California, Los Angeles, CA 90095 (USA)
| | - Ga Young Lee
- Department of Chemistry and Biochemistry, University of California, Los Angeles, CA 90095 (USA)
| | - Joseph W. Treacy
- Department of Chemistry and Biochemistry, University of California, Los Angeles, CA 90095 (USA)
| | - Aneta Turlik
- Department of Chemistry and Biochemistry, University of California, Los Angeles, CA 90095 (USA)
| | - Saeed I. Khan
- Department of Chemistry and Biochemistry, University of California, Los Angeles, CA 90095 (USA)
| | - K. N. Houk
- Department of Chemistry and Biochemistry, University of California, Los Angeles, CA 90095 (USA)
| | - Michael E. Jung
- Department of Chemistry and Biochemistry, University of California, Los Angeles, CA 90095 (USA)
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10
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Kukier GA, Turlik A, Xue XS, Houk KN. Violations. How Nature Circumvents the Woodward-Hoffmann Rules and Promotes the Forbidden Conrotatory 4 n + 2 Electron Electrocyclization of Prinzbach's Vinylogous Sesquifulvalene. J Am Chem Soc 2021; 143:21694-21704. [PMID: 34911295 DOI: 10.1021/jacs.1c11058] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/04/2023]
Abstract
Woodward and Hoffmann, in their treatise on orbital symmetry in 1969, stated "Violations. There are none!" Prinzbach reported in 1978 that the electrocyclization of vinylogous sesquifulvalene occurs exclusively through the Woodward-Hoffmann orbital-symmetry-forbidden 14π-electron conrotatory pathway, despite the availability of a variety of orbital-symmetry-allowed processes. Prinzbach later demonstrated that an 18π-electron homologue exhibits the same forbidden behavior. And yet, the analogous vinylogous pentafulvalene and heptafulvalene both follow the orbital symmetry rules, each proceeding through its allowed conrotatory 12π and 16π process, respectively. We report the investigation of these reactions with ωB97X-D DFT. The physical origins of the flagrant Prinzbach violations of the Woodward-Hoffmann orbital symmetry selection rules have now been elucidated by these calculations in conjunction with extensive analyses and comparisons to electrocyclizations that obey the Woodward-Hoffmann rules. This remarkable reversal of the Rules (the 14π-electron-forbidden process is found to be 11 kcal/mol more energetically facile than the allowed process) occurs due to the high degree of polarization of this hydrocarbon, such that conrotatory electrocyclization of vinylogous sesquifulvalene behaves like a cyclopentadienide combining with a tropylium. These results are compared to other forbidden pericyclic processes driven by steric constraints and strain release or by diradical character of the reactants that facilitates the formation of diradical transition states for symmetry-forbidden reactions. We predict how strong donor-acceptor substitution can modify nodal properties to level the difference between allowed and forbidden electrocyclic reaction barriers, and we provide computational predictions of two such cases.
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Affiliation(s)
- Garrett A Kukier
- Department of Chemistry and Biochemistry, University of California, Los Angeles, California 90095, United States
| | - Aneta Turlik
- Department of Chemistry and Biochemistry, University of California, Los Angeles, California 90095, United States
| | - Xiao-Song Xue
- Department of Chemistry and Biochemistry, University of California, Los Angeles, California 90095, 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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Abstract
![]()
Pyridyl tetrazines
coordinated to metals like rhenium have been
shown to be more reactive in [4 + 2] cycloadditions than their uncomplexed
counterparts. Using density functional theory calculations, we found
a more favorable interaction energy caused by stronger orbital interactions
as the origin of this increased reactivity. Additionally, the high
regioselectivity is due to a greater degree of charge stabilization
in the transition state, leading to the major product.
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Affiliation(s)
- Aneta Turlik
- Department of Chemistry and Biochemistry, University of California, Los Angeles, California 90095-1569, United States
| | - K N Houk
- Department of Chemistry and Biochemistry, University of California, Los Angeles, California 90095-1569, United States
| | - Dennis Svatunek
- Institute of Applied Synthetic Chemistry, TU Wien, 1060 Vienna, Austria
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12
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Mackey P, Turlik A, Ando K, Light ME, Houk KN, McGlacken GP. Stereoselective Installation of Five Contiguous Stereogenic Centers in a Double Aldol-Tishchenko Cascade and Evaluation of the Key Transition State through DFT Calculation. Org Lett 2021; 23:6372-6376. [PMID: 34374288 PMCID: PMC8383304 DOI: 10.1021/acs.orglett.1c02179] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
![]()
The stereoselective formation of
5 contiguous chiral centers in
a single pot reaction is demonstrated using an aldol, aldol–Tishchenko
reaction of N-tert-butyl sulfinimines.
One diastereoisomer (from 32 possibilities) predominates, and a series
of cyclic and acyclic 3-amino-1,5-diol derivatives are synthesized
in good yields (up to 80%) and excellent diastereoselectivities (up
to >98:2 dr). Investigations support two reversible aldol steps,
and
multiple intermediates which are funnelled through a remarkably selective,
irreversible, Tishchenko reduction, in a Curtin–Hammett phenomenon.
DFT calculations using a disolvated (THF) model reveal the factors
controlling stereoselectivity in the final irreversible Tishchenko
step.
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Affiliation(s)
- Pamela Mackey
- School of Chemistry and Analytical and Biological Chemistry Research Facility, University College Cork, Cork, Ireland
| | - Aneta Turlik
- Department of Chemistry and Biochemistry, University of California, Los Angeles, California 90095-1569, United States
| | - Kaori Ando
- Department of Chemistry and Biomolecular Science, Faculty of Engineering, Gifu University, Yanagido 1-1, Gifu 501-1193, Japan
| | - Mark E Light
- University of Southampton, Chemistry Department, University Road, Southampton SO17 1BJ, United Kingdom
| | - K N Houk
- Department of Chemistry and Biochemistry, University of California, Los Angeles, California 90095-1569, United States
| | - Gerard P McGlacken
- School of Chemistry and Analytical and Biological Chemistry Research Facility, University College Cork, Cork, Ireland
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13
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Turlik A, Ando K, Mackey P, Alcock E, Light M, McGlacken GP, Houk KN. Mechanism and Origins of Stereoselectivity of the Aldol-Tishchenko Reaction of Sulfinimines. J Org Chem 2021; 86:4296-4303. [PMID: 33586983 PMCID: PMC8279497 DOI: 10.1021/acs.joc.0c02862] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
![]()
Density functional theory computations
have elucidated the mechanism
and origins of stereoselectivity in McGlacken’s aldol-Tishchenko
reaction for the diastereoselective synthesis of 1,3-amino alcohols
using Ellman’s t-butylsulfinimines as chiral
auxiliaries. Variations of stereochemical outcome are dependent on
the nature of the ketone starting materials used, and the aspects
leading to these differences have been rationalized. The intramolecular
hydride transfer step is the rate- and stereochemistry-determining
step, and all prior steps are reversible.
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Affiliation(s)
- Aneta Turlik
- Department of Chemistry and Biochemistry, University of California, Los Angeles, California 90095-1569, United States
| | - Kaori Ando
- Department of Chemistry and Biomolecular Science, Faculty of Engineering, Gifu University, Yanagido 1-1, Gifu 501-1193, Japan
| | - Pamela Mackey
- School of Chemistry and Analytical and Biological Chemistry Research Facility, University College Cork, Cork, Ireland
| | - Emma Alcock
- School of Chemistry and Analytical and Biological Chemistry Research Facility, University College Cork, Cork, Ireland
| | - Mark Light
- School of Chemistry, University of Southampton, Southampton, SO17 1BJ, United Kingdom
| | - Gerard P McGlacken
- School of Chemistry and Analytical and Biological Chemistry Research Facility, University College Cork, Cork, Ireland
| | - K N Houk
- Department of Chemistry and Biochemistry, University of California, Los Angeles, California 90095-1569, United States
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14
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Li B, Tang H, Turlik A, Wan Z, Xue X, Li L, Yang X, Li J, He G, Houk KN, Chen G. Cooperative Stapling of Native Peptides at Lysine and Tyrosine or Arginine with Formaldehyde. Angew Chem Int Ed Engl 2021; 60:6646-6652. [DOI: 10.1002/anie.202016267] [Citation(s) in RCA: 12] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/07/2020] [Indexed: 12/14/2022]
Affiliation(s)
- Bo Li
- State Key Laboratory and Institute of Elemento-Organic Chemistry College of Chemistry Nankai University Tianjin 300071 China
| | - Hong Tang
- State Key Laboratory and Institute of Elemento-Organic Chemistry College of Chemistry Nankai University Tianjin 300071 China
| | - Aneta Turlik
- Department of Chemistry and Biochemistry University of California Los Angeles CA 90095 USA
| | - Zhao Wan
- State Key Laboratory and Institute of Elemento-Organic Chemistry College of Chemistry Nankai University Tianjin 300071 China
| | - Xiao‐Song Xue
- State Key Laboratory and Institute of Elemento-Organic Chemistry College of Chemistry Nankai University Tianjin 300071 China
- Department of Chemistry and Biochemistry University of California Los Angeles CA 90095 USA
| | - Li Li
- Beijing Key Laboratory of Active Substances Discovery and Druggability Evaluation Institute of Materia Medica Chinese Academy of Medical Sciences Peking Union Medical College Beijing 100050 China
| | - Xiaoxiao Yang
- Beijing Key Laboratory of Active Substances Discovery and Druggability Evaluation Institute of Materia Medica Chinese Academy of Medical Sciences Peking Union Medical College Beijing 100050 China
| | - Jiuyuan Li
- Asymchem Life Science Co., Ltd. TEDA Tianjin 300457 China
| | - Gang He
- State Key Laboratory and Institute of Elemento-Organic Chemistry College of Chemistry Nankai University Tianjin 300071 China
| | - Kendall N. Houk
- Department of Chemistry and Biochemistry University of California Los Angeles CA 90095 USA
| | - Gong Chen
- State Key Laboratory and Institute of Elemento-Organic Chemistry College of Chemistry Nankai University Tianjin 300071 China
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15
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Li B, Tang H, Turlik A, Wan Z, Xue X, Li L, Yang X, Li J, He G, Houk KN, Chen G. Cooperative Stapling of Native Peptides at Lysine and Tyrosine or Arginine with Formaldehyde. Angew Chem Int Ed Engl 2021. [DOI: 10.1002/ange.202016267] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Affiliation(s)
- Bo Li
- State Key Laboratory and Institute of Elemento-Organic Chemistry College of Chemistry Nankai University Tianjin 300071 China
| | - Hong Tang
- State Key Laboratory and Institute of Elemento-Organic Chemistry College of Chemistry Nankai University Tianjin 300071 China
| | - Aneta Turlik
- Department of Chemistry and Biochemistry University of California Los Angeles CA 90095 USA
| | - Zhao Wan
- State Key Laboratory and Institute of Elemento-Organic Chemistry College of Chemistry Nankai University Tianjin 300071 China
| | - Xiao‐Song Xue
- State Key Laboratory and Institute of Elemento-Organic Chemistry College of Chemistry Nankai University Tianjin 300071 China
- Department of Chemistry and Biochemistry University of California Los Angeles CA 90095 USA
| | - Li Li
- Beijing Key Laboratory of Active Substances Discovery and Druggability Evaluation Institute of Materia Medica Chinese Academy of Medical Sciences Peking Union Medical College Beijing 100050 China
| | - Xiaoxiao Yang
- Beijing Key Laboratory of Active Substances Discovery and Druggability Evaluation Institute of Materia Medica Chinese Academy of Medical Sciences Peking Union Medical College Beijing 100050 China
| | - Jiuyuan Li
- Asymchem Life Science Co., Ltd. TEDA Tianjin 300457 China
| | - Gang He
- State Key Laboratory and Institute of Elemento-Organic Chemistry College of Chemistry Nankai University Tianjin 300071 China
| | - Kendall N. Houk
- Department of Chemistry and Biochemistry University of California Los Angeles CA 90095 USA
| | - Gong Chen
- State Key Laboratory and Institute of Elemento-Organic Chemistry College of Chemistry Nankai University Tianjin 300071 China
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16
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Bogart JW, Kramer NJ, Turlik A, Bleich RM, Catlin DS, Schroeder FC, Nair SK, Williamson RT, Houk KN, Bowers AA. Interception of the Bycroft-Gowland Intermediate in the Enzymatic Macrocyclization of Thiopeptides. J Am Chem Soc 2020; 142:13170-13179. [PMID: 32609512 DOI: 10.1021/jacs.0c05639] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022]
Abstract
Thiopeptides are a broad class of macrocyclic, heavily modified peptide natural products that are unified by the presence of a substituted, nitrogen-containing heterocycle core. Early work indicated that this core might be fashioned from two dehydroalanines by an enzyme-catalyzed aza-[4 + 2] cycloaddition to give a cyclic-hemiaminal intermediate. This common intermediate could then follow a reductive path toward a dehydropiperidine, as in the thiopeptide thiostrepton, or an aromatization path to yield the pyridine groups observed in many other thiopeptides. Although several of the enzymes proposed to perform this cycloaddition have been reconstituted, only pyridine products have been isolated and any hemiaminal intermediates have yet to be observed. Here, we identify the conditions and substrates that decouple the cycloaddition from subsequent steps and allow interception and characterization of this long hypothesized intermediate. Transition state modeling indicates that the key amide-iminol tautomerization is the major hurdle in an otherwise energetically favorable cycloaddition. An anionic model suggests that deprotonation and polarization of this amide bond by TbtD removes this barrier and provides a sufficient driving force for facile (stepwise) cycloaddition. This work provides evidence for a mechanistic link between disparate cyclases in thiopeptide biosynthesis.
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Affiliation(s)
- Jonathan W Bogart
- Division of Chemical Biology and Medicinal Chemistry, UNC Eshelman School of Pharmacy, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina 27599, United States
| | - Nicholas J Kramer
- Division of Chemical Biology and Medicinal Chemistry, UNC Eshelman School of Pharmacy, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina 27599, United States
| | - Aneta Turlik
- Department of Chemistry and Biochemistry, University of California, Los Angeles, California 90095, United States
| | - Rachel M Bleich
- Division of Chemical Biology and Medicinal Chemistry, UNC Eshelman School of Pharmacy, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina 27599, United States
| | - Daniel S Catlin
- Department of Biochemistry, University of Illinois at Urbana-Champaign, Urbana, Illinois 61801, United States
| | - Frank C Schroeder
- Boyce Thompson Institute and Department of Chemistry and Chemical Biology, Ithaca, New York 14853, United States
| | - Satish K Nair
- Department of Biochemistry, University of Illinois at Urbana-Champaign, Urbana, Illinois 61801, United States.,Center for Biophysics and Computational Biology, University of Illinois at Urbana-Champaign, Urbana, Illinois 61801, United States
| | - R Thomas Williamson
- Department of Chemistry and Biochemistry, University of North Carolina Wilmington, Wilmington, North Carolina 28403, United States
| | - K N Houk
- Department of Chemistry and Biochemistry, University of California, Los Angeles, California 90095, United States
| | - Albert A Bowers
- Division of Chemical Biology and Medicinal Chemistry, UNC Eshelman School of Pharmacy, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina 27599, United States.,Department of Chemistry, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina 27599, United States
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17
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Debrauwer V, Turlik A, Rummler L, Prescimone A, Blanchard N, Houk KN, Bizet V. Ligand-Controlled Regiodivergent Palladium-Catalyzed Hydrogermylation of Ynamides. J Am Chem Soc 2020; 142:11153-11164. [DOI: 10.1021/jacs.0c03556] [Citation(s) in RCA: 36] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022]
Affiliation(s)
- Vincent Debrauwer
- Université de Haute-Alsace, Université de Strasbourg, CNRS, LIMA, UMR 7042, 68000 Mulhouse, France
| | - Aneta Turlik
- Department of Chemistry and Biochemistry, University of California, Los Angeles, California 90095, United States
| | - Lénaic Rummler
- Université de Haute-Alsace, Université de Strasbourg, CNRS, LIMA, UMR 7042, 68000 Mulhouse, France
| | - Alessandro Prescimone
- Chemistry Department, University of Basel, Mattenstrasse 24a, 4058 Basel, Switzerland
| | - Nicolas Blanchard
- Université de Haute-Alsace, Université de Strasbourg, CNRS, LIMA, UMR 7042, 68000 Mulhouse, France
| | - K. N. Houk
- Department of Chemistry and Biochemistry, University of California, Los Angeles, California 90095, United States
| | - Vincent Bizet
- Université de Haute-Alsace, Université de Strasbourg, CNRS, LIMA, UMR 7042, 68000 Mulhouse, France
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18
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Sun DL, Poddar S, Pan RD, Rosser EW, Abt ER, Van Valkenburgh J, Le TM, Lok V, Hernandez SP, Song J, Li J, Turlik A, Chen X, Cheng CA, Chen W, Mona CE, Stuparu AD, Vergnes L, Reue K, Damoiseaux R, Zink JI, Czernin J, Donahue TR, Houk KN, Jung ME, Radu CG. Isoquinoline thiosemicarbazone displays potent anticancer activity with in vivo efficacy against aggressive leukemias. RSC Med Chem 2020; 11:392-410. [PMID: 33479645 DOI: 10.1039/c9md00594c] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/26/2019] [Accepted: 02/12/2020] [Indexed: 11/21/2022] Open
Abstract
A potent class of isoquinoline-based α-N-heterocyclic carboxaldehyde thiosemicarbazone (HCT) compounds has been rediscovered; based upon this scaffold, three series of antiproliferative agents were synthesized through iterative rounds of methylation and fluorination modifications, with anticancer activities being potentiated by physiologically relevant levels of copper. The lead compound, HCT-13, was highly potent against a panel of pancreatic, small cell lung carcinoma, prostate cancer, and leukemia models, with IC50 values in the low-to-mid nanomolar range. Density functional theory (DFT) calculations showed that fluorination at the 6-position of HCT-13 was beneficial for ligand-copper complex formation, stability, and ease of metal-center reduction. Through a chemical genomics screen, we identify DNA damage response/replication stress response (DDR/RSR) pathways, specifically those mediated by ataxia-telangiectasia and Rad3-related protein kinase (ATR), as potential compensatory mechanism(s) of action following HCT-13 treatment. We further show that the cytotoxicity of HCT-13 is copper-dependent, that it promotes mitochondrial electron transport chain (mtETC) dysfunction, induces production of reactive oxygen species (ROS), and selectively depletes guanosine nucleotide pools. Lastly, we identify metabolic hallmarks for therapeutic target stratification and demonstrate the in vivo efficacy of HCT-13 against aggressive models of acute leukemias in mice.
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Affiliation(s)
- Daniel L Sun
- Department of Molecular and Medical Pharmacology , University of California, Los Angeles , California 90095 , USA . .,Ahmanson Translational Imaging Division , University of California, Los Angeles , California 90095 , USA.,Department of Chemistry and Biochemistry , University of California, Los Angeles , California 90095 , USA .
| | - Soumya Poddar
- Department of Molecular and Medical Pharmacology , University of California, Los Angeles , California 90095 , USA . .,Ahmanson Translational Imaging Division , University of California, Los Angeles , California 90095 , USA
| | - Roy D Pan
- Department of Molecular and Medical Pharmacology , University of California, Los Angeles , California 90095 , USA . .,Ahmanson Translational Imaging Division , University of California, Los Angeles , California 90095 , USA.,Department of Chemistry and Biochemistry , University of California, Los Angeles , California 90095 , USA .
| | - Ethan W Rosser
- Department of Molecular and Medical Pharmacology , University of California, Los Angeles , California 90095 , USA . .,Ahmanson Translational Imaging Division , University of California, Los Angeles , California 90095 , USA.,Department of Chemistry and Biochemistry , University of California, Los Angeles , California 90095 , USA .
| | - Evan R Abt
- Department of Molecular and Medical Pharmacology , University of California, Los Angeles , California 90095 , USA . .,Ahmanson Translational Imaging Division , University of California, Los Angeles , California 90095 , USA
| | - Juno Van Valkenburgh
- Department of Molecular and Medical Pharmacology , University of California, Los Angeles , California 90095 , USA . .,Ahmanson Translational Imaging Division , University of California, Los Angeles , California 90095 , USA.,Department of Chemistry and Biochemistry , University of California, Los Angeles , California 90095 , USA .
| | - Thuc M Le
- Department of Molecular and Medical Pharmacology , University of California, Los Angeles , California 90095 , USA . .,Ahmanson Translational Imaging Division , University of California, Los Angeles , California 90095 , USA
| | - Vincent Lok
- Department of Molecular and Medical Pharmacology , University of California, Los Angeles , California 90095 , USA .
| | - Selena P Hernandez
- Department of Chemistry and Biochemistry , University of California, Los Angeles , California 90095 , USA .
| | - Janet Song
- Department of Molecular and Medical Pharmacology , University of California, Los Angeles , California 90095 , USA .
| | - Joanna Li
- Department of Molecular and Medical Pharmacology , University of California, Los Angeles , California 90095 , USA .
| | - Aneta Turlik
- Department of Chemistry and Biochemistry , University of California, Los Angeles , California 90095 , USA .
| | - Xiaohong Chen
- Department of Chemistry and Biochemistry , University of California, Los Angeles , California 90095 , USA .
| | - Chi-An Cheng
- Department of Chemistry and Biochemistry , University of California, Los Angeles , California 90095 , USA . .,Department of Bioengineering , University of California, Los Angeles , CA 90095 , USA
| | - Wei Chen
- Department of Chemistry and Biochemistry , University of California, Los Angeles , California 90095 , USA .
| | - Christine E Mona
- Department of Molecular and Medical Pharmacology , University of California, Los Angeles , California 90095 , USA . .,Ahmanson Translational Imaging Division , University of California, Los Angeles , California 90095 , USA
| | - Andreea D Stuparu
- Department of Molecular and Medical Pharmacology , University of California, Los Angeles , California 90095 , USA . .,Ahmanson Translational Imaging Division , University of California, Los Angeles , California 90095 , USA
| | - Laurent Vergnes
- Department of Human Genetics , David Geffen School of Medicine , University of California, Los Angeles , California 90095 , USA
| | - Karen Reue
- Department of Human Genetics , David Geffen School of Medicine , University of California, Los Angeles , California 90095 , USA.,Molecular Biology Institute , University of California, Los Angeles , California 90095 , USA
| | - Robert Damoiseaux
- UCLA Metabolomic Center , University of California, Los Angeles , Los Angeles , California 90095 , USA
| | - Jeffrey I Zink
- Department of Chemistry and Biochemistry , University of California, Los Angeles , California 90095 , USA .
| | - Johannes Czernin
- Department of Molecular and Medical Pharmacology , University of California, Los Angeles , California 90095 , USA . .,Ahmanson Translational Imaging Division , University of California, Los Angeles , California 90095 , USA
| | - Timothy R Donahue
- Department of Molecular and Medical Pharmacology , University of California, Los Angeles , California 90095 , USA . .,Ahmanson Translational Imaging Division , University of California, Los Angeles , California 90095 , USA.,Department of Surgery , University of California, Los Angeles , CA 90095 , USA
| | - Kendall N Houk
- Department of Chemistry and Biochemistry , University of California, Los Angeles , California 90095 , USA .
| | - Michael E Jung
- Department of Chemistry and Biochemistry , University of California, Los Angeles , California 90095 , USA .
| | - Caius G Radu
- Department of Molecular and Medical Pharmacology , University of California, Los Angeles , California 90095 , USA . .,Ahmanson Translational Imaging Division , University of California, Los Angeles , California 90095 , USA
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Abstract
The total synthesis of principinol D, a rearranged kaurane diterpenoid, is reported. This grayanane natural product is constructed via a convergent fragment coupling approach, wherein the central seven-membered ring is synthesized at a late stage. The bicyclo[3.2.1]octane fragment is accessed by a Ni-catalyzed α-vinylation reaction. Strategic reductions include a diastereoselective SmI2-mediated ketone reduction with PhSH and a new protocol for selective ester reduction in the presence of ketones. The convergent strategy reported herein may be an entry point to the larger class of kaurane diterpenoids.
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Affiliation(s)
- Aneta Turlik
- Department of Chemistry, Yale University, 225 Prospect Street, New Haven, Connecticut 06520-8107, United States
| | - Yifeng Chen
- Department of Chemistry, Yale University, 225 Prospect Street, New Haven, Connecticut 06520-8107, United States
| | - Anthony C. Scruse
- Department of Chemistry, Yale University, 225 Prospect Street, New Haven, Connecticut 06520-8107, United States
| | - Timothy R. Newhouse
- Department of Chemistry, Yale University, 225 Prospect Street, New Haven, Connecticut 06520-8107, United States
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20
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Elkin M, Scruse AC, Turlik A, Newhouse TR. Computational and Synthetic Investigation of Cationic Rearrangement in the Putative Biosynthesis of Justicane Triterpenoids. Angew Chem Int Ed Engl 2019; 58:1025-1029. [PMID: 30575223 PMCID: PMC6499374 DOI: 10.1002/anie.201810566] [Citation(s) in RCA: 16] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/13/2018] [Revised: 10/30/2018] [Indexed: 02/06/2023]
Abstract
A biomimetic cationic structural rearrangement of the oleanolic acid framework is reported for the gram-scale synthesis and structural reassignment of justicioside E aglycone. The mechanism of the putative biosynthetic rearrangement is investigated with kinetic, computational, and synthetic approaches. The precursor to rearrangement was accessed through two strategic advancements: (1) synthesis of a 1,3-diketone via oxidation of a β-silyl enone, and (2) diastereoselective 1,3-diketone reduction to form a syn-1,3-diol using SmI2 with PhSH as a key additive.
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Affiliation(s)
- Masha Elkin
- Department of Chemistry, Yale University, 225 Prospect Street, PO Box 20817, New Haven, CT, 06511, USA
| | - Anthony C Scruse
- Department of Chemistry, Yale University, 225 Prospect Street, PO Box 20817, New Haven, CT, 06511, USA
| | - Aneta Turlik
- Department of Chemistry, Yale University, 225 Prospect Street, PO Box 20817, New Haven, CT, 06511, USA
| | - Timothy R Newhouse
- Department of Chemistry, Yale University, 225 Prospect Street, PO Box 20817, New Haven, CT, 06511, USA
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21
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Elkin M, Scruse AC, Turlik A, Newhouse TR. Computational and Synthetic Investigation of Cationic Rearrangement in the Putative Biosynthesis of Justicane Triterpenoids. Angew Chem Int Ed Engl 2018. [DOI: 10.1002/ange.201810566] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
Affiliation(s)
- Masha Elkin
- Department of ChemistryYale University 225 Prospect Street, PO Box 20817 New Haven CT 06511 USA
| | - Anthony C. Scruse
- Department of ChemistryYale University 225 Prospect Street, PO Box 20817 New Haven CT 06511 USA
| | - Aneta Turlik
- Department of ChemistryYale University 225 Prospect Street, PO Box 20817 New Haven CT 06511 USA
| | - Timothy R. Newhouse
- Department of ChemistryYale University 225 Prospect Street, PO Box 20817 New Haven CT 06511 USA
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22
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Newhouse T, Turlik A, Chen Y. Dehydrogenation Adjacent to Carbonyls Using Palladium–Allyl Intermediates. Synlett 2016. [DOI: 10.1055/s-0035-1560427] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/22/2022]
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23
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Abstract
A practical and direct method for the α,β-dehydrogenation of amides is reported using allyl-palladium catalysis. Critical to the success of this process was the synthesis and application of a novel lithium N-cyclohexyl anilide (LiCyan). The reaction conditions tolerate a wide variety of substrates, including those with acidic heteroatom nucleophiles.
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Affiliation(s)
- Yifeng Chen
- Department of Chemistry, Yale University , 275 Prospect Street, New Haven, Connecticut 06520-8107, United States
| | - Aneta Turlik
- Department of Chemistry, Yale University , 275 Prospect Street, New Haven, Connecticut 06520-8107, United States
| | - Timothy R Newhouse
- Department of Chemistry, Yale University , 275 Prospect Street, New Haven, Connecticut 06520-8107, United States
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