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Miller DC, Lal RG, Marchetti LA, Arnold FH. Biocatalytic One-Carbon Ring Expansion of Aziridines to Azetidines via a Highly Enantioselective [1,2]-Stevens Rearrangement. J Am Chem Soc 2022; 144:4739-4745. [PMID: 35258294 PMCID: PMC9022672 DOI: 10.1021/jacs.2c00251] [Citation(s) in RCA: 23] [Impact Index Per Article: 11.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/25/2023]
Abstract
We report enantioselective one-carbon ring expansion of aziridines to make azetidines as a new-to-nature activity of engineered "carbene transferase" enzymes. A laboratory-evolved variant of cytochrome P450BM3, P411-AzetS, not only exerts unparalleled stereocontrol (99:1 er) over a [1,2]-Stevens rearrangement but also overrides the inherent reactivity of aziridinium ylides, cheletropic extrusion of olefins, to perform a [1,2]-Stevens rearrangement. By controlling the fate of the highly reactive aziridinium ylide intermediates, these evolvable biocatalysts promote a transformation which cannot currently be performed using other catalyst classes.
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Affiliation(s)
- David C. Miller
- Division of Chemistry and Chemical Engineering, California Institute of Technology, Pasadena, California 91125, United States
| | - Ravi G. Lal
- Division of Chemistry and Chemical Engineering, California Institute of Technology, Pasadena, California 91125, United States
| | - Luca A. Marchetti
- Division of Chemistry and Chemical Engineering, California Institute of Technology, Pasadena, California 91125, United States
- Present Address: Department of Biosystems Science and Engineering, ETH Zürich, 4058 Basel, Switzerland
| | - Frances H. Arnold
- Division of Chemistry and Chemical Engineering, California Institute of Technology, Pasadena, California 91125, United States
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Kratena N, Gökler T, Maltrovsky L, Oburger E, Stanetty C. A Unified Approach to Phytosiderophore Natural Products. Chemistry 2021; 27:577-580. [PMID: 32897577 PMCID: PMC7821100 DOI: 10.1002/chem.202004004] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/02/2020] [Indexed: 11/10/2022]
Abstract
This work reports on the concise total synthesis of eight natural products of the mugineic acid and avenic acid families (phytosiderophores). An innovative "east-to-west" assembly of the trimeric products resulted in a high degree of divergence enabling the formation of the final products in just 10 or 11 steps each with a minimum of overall synthetic effort. Chiral pool starting materials (l-malic acid, threonines) were employed for the outer building blocks while the middle building blocks were accessed by diastereo- and enantioselective methods. A highlight of this work consists in the straightforward preparation of epimeric hydroxyazetidine amino acids, useful building blocks on their own, enabling the first synthesis of 3''-hydroxymugineic acid and 3''-hydroxy-2'-deoxymugineic acid.
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Affiliation(s)
- Nicolas Kratena
- Institute of Applied Synthetic ChemistryTU WienGetreidemarkt 91060ViennaAustria
| | - Tobias Gökler
- Institute of Applied Synthetic ChemistryTU WienGetreidemarkt 91060ViennaAustria
| | - Lara Maltrovsky
- Institute of Applied Synthetic ChemistryTU WienGetreidemarkt 91060ViennaAustria
| | - Eva Oburger
- Institute of Soil ResearchBOKU ViennaKonrad-Lorenz-Strasse 243430TullnAustria
| | - Christian Stanetty
- Institute of Applied Synthetic ChemistryTU WienGetreidemarkt 91060ViennaAustria
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Reiners F, Joseph E, Nißl B, Didier D. Stereoselective Access to Azetidine-Based α-Amino Acids and Applications to Small Peptide Synthesis. Org Lett 2020; 22:8533-8537. [PMID: 33052683 DOI: 10.1021/acs.orglett.0c03131] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Non-natural azetidine-based amino acids (Aze) present interesting features in protein engineering. A simple organometallic route toward unsaturated carboxylic acid precursors is presented. Subsequent metal-catalyzed asymmetric reduction allowed for the synthesis of a new library of 2-azetidinylcarboxylic acids, which were finally employed in the formation of small peptide chains.
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Affiliation(s)
- Felix Reiners
- Department of Chemistry and Pharmacy, Ludwig-Maximilians-Universität München, Butenandtstraße 5-13, 81377 Munich, Germany
| | - Emanuel Joseph
- Department of Chemistry and Pharmacy, Ludwig-Maximilians-Universität München, Butenandtstraße 5-13, 81377 Munich, Germany
| | - Benedikt Nißl
- Department of Chemistry and Pharmacy, Ludwig-Maximilians-Universität München, Butenandtstraße 5-13, 81377 Munich, Germany
| | - Dorian Didier
- Department of Chemistry and Pharmacy, Ludwig-Maximilians-Universität München, Butenandtstraße 5-13, 81377 Munich, Germany
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Foletti C, Trapp N, Loosli S, Lewandowski B, Wennemers H. 4‐Naphthylmethyl Proline Forms a Channel Structure. Helv Chim Acta 2019. [DOI: 10.1002/hlca.201900052] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/28/2022]
Affiliation(s)
- Carlotta Foletti
- Laboratorium für Organische Chemie, D-CHABETH Zurich Vladimir-Prelog-Weg 3 CH-8093 Zurich
| | - Nils Trapp
- Laboratorium für Organische Chemie, D-CHABETH Zurich Vladimir-Prelog-Weg 3 CH-8093 Zurich
| | - Simon Loosli
- Laboratorium für Organische Chemie, D-CHABETH Zurich Vladimir-Prelog-Weg 3 CH-8093 Zurich
| | - Bartosz Lewandowski
- Laboratorium für Organische Chemie, D-CHABETH Zurich Vladimir-Prelog-Weg 3 CH-8093 Zurich
| | - Helma Wennemers
- Laboratorium für Organische Chemie, D-CHABETH Zurich Vladimir-Prelog-Weg 3 CH-8093 Zurich
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Biswas T, Mukherjee JP, Chattopadhyay SK. Enantiodivergent synthesis of N-protected azetidine-2-carboxylic acid. ACTA ACUST UNITED AC 2012. [DOI: 10.1016/j.tetasy.2012.08.016] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
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Affiliation(s)
- Stephen Hanessian
- Department of Chemistry, Université de Montréal, C.P. 6128, Succursale
Centre-Ville Montréal, Québec H3C 3J7, Canada
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Bouazaoui M, Martinez J, Cavelier F. Direct Access to L-Azetidine-2-carboxylic Acid. European J Org Chem 2009. [DOI: 10.1002/ejoc.200900233] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
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8
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Xu Y, Lu G, Matsunaga S, Shibasaki M. Direct anti-selective catalytic asymmetric Mannich-type reactions of alpha-ketoanilides for the synthesis of gamma-amino amides and azetidine-2-amides. Angew Chem Int Ed Engl 2009; 48:3353-6. [PMID: 19334031 DOI: 10.1002/anie.200900670] [Citation(s) in RCA: 78] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
Abstract
Breaking with convention: A homodinuclear nickel complex derived from a biphenyldiamine-based Schiff base catalyzed an anti-selective Mannich-type reaction of alpha-ketoanilides (see scheme) to afford unique building blocks for the synthesis of azetidine-2-amides and alpha-hydroxy gamma-amino amides. This approach stands in contrast to conventional Mannich-type reactions for the synthesis of beta-amino carbonyl compounds. o-Ns = o-nitrobenzenesulfonyl.
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Affiliation(s)
- Yingjie Xu
- Graduate School of Pharmaceutical Sciences, The University of Tokyo, Hongo, Bunkyo-ku, Tokyo 113-0033, Japan
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Xu Y, Lu G, Matsunaga S, Shibasaki M. Directanti-Selective Catalytic Asymmetric Mannich-Type Reactions of α-Ketoanilides for the Synthesis of γ-Amino Amides and Azetidine-2-amides. Angew Chem Int Ed Engl 2009. [DOI: 10.1002/ange.200900670] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
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Bragnier N, Guillot R, Scherrmann MC. Diastereoselective addition of sugar radicals to camphorsultam glyoxilic oxime ether: a route toward C-glycosylthreonine and allothreonine. Org Biomol Chem 2009; 7:3918-21. [DOI: 10.1039/b910050d] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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Sajjadi Z, Lubell WD. Amino acid-azetidine chimeras: synthesis of enantiopure 3-substituted azetidine-2-carboxylic acids. ACTA ACUST UNITED AC 2008; 65:298-310. [PMID: 15705172 DOI: 10.1111/j.1399-3011.2005.00228.x] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Azetidine-2-carboxylic acid (Aze) analogs possessing various heteroatomic side chains at the 3-position have been synthesized by modification of 1-9-(9-phenylfluorenyl) (PhF)-3-allyl-Aze tert-butyl ester (2S,3S)-1. 3-Allyl-Aze 1 was synthesized by regioselective allylation of alpha-tert-butyl beta-methyl N-(PhF)aspartate 13, followed by selective omega-carboxylate reduction, tosylation, and intramolecular N-alkylation. Removal of the PhF group and olefin reduction by hydrogenation followed by Fmoc protection produced nor-leucine-Aze chimera 2. Regioselective olefin hydroboration of (2S,3S)-1 produced primary alcohol 23, which was protected as a silyl ether, hydrogenated and N-protected to give 1-Fmoc-3-hydroxypropyl-Aze 26. Enantiopure (2S,3S)-3-(3-azidopropyl)-1-Fmoc-azetidine-2-carboxylic acid tert-butyl ester 3 was prepared as a Lys-Aze chimera by activation of 3-hydroxypropyl-Aze 26 as a methanesulfonate and displacement with sodium azide. Moreover, orthogonally protected azetidine dicarboxylic acid 4 was synthesized as an alpha-aminoadipate-Aze chimera by oxidation of alcohol 26. These orthogonally protected amino acid-Aze chimeras are designed to serve as tools for studying the influence of conformation on peptide activity.
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Affiliation(s)
- Z Sajjadi
- Departement de Chimie, Université de Montréal, C.P.6128 Succursale, Centre Ville, Montréal, Québec, Canada
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Morimoto H, Yoshino T, Yukawa T, Lu G, Matsunaga S, Shibasaki M. Lewis Base Assisted Brønsted Base Catalysis: Bidentate Phosphine Oxides as Activators and Modulators of Brønsted Basic Lanthanum-Aryloxides. Angew Chem Int Ed Engl 2008. [DOI: 10.1002/ange.200803682] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
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13
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Morimoto H, Yoshino T, Yukawa T, Lu G, Matsunaga S, Shibasaki M. Lewis Base Assisted Brønsted Base Catalysis: Bidentate Phosphine Oxides as Activators and Modulators of Brønsted Basic Lanthanum-Aryloxides. Angew Chem Int Ed Engl 2008; 47:9125-9. [DOI: 10.1002/anie.200803682] [Citation(s) in RCA: 48] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
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14
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Burtoloso ACB, Correia CRD. Stereoselective synthesis of azetidine-derived glutamate and aspartate analogues from chiral azetidin-3-ones. Tetrahedron 2008. [DOI: 10.1016/j.tet.2008.08.001] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
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Brandi A, Cicchi S, Cordero FM. Novel Syntheses of Azetidines and Azetidinones. Chem Rev 2008; 108:3988-4035. [DOI: 10.1021/cr800325e] [Citation(s) in RCA: 395] [Impact Index Per Article: 24.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/08/2023]
Affiliation(s)
- Alberto Brandi
- Dipartimento di Chimica Organica “Ugo Schiff”, Laboratorio di Progettazione, Sintesi e Studio di Eterocicli Biologicamente Attivi - HeteroBioLab, Università degli Studi di Firenze, via della Lastruccia 13, 50019 Sesto F.no (FI), Italy
| | - Stefano Cicchi
- Dipartimento di Chimica Organica “Ugo Schiff”, Laboratorio di Progettazione, Sintesi e Studio di Eterocicli Biologicamente Attivi - HeteroBioLab, Università degli Studi di Firenze, via della Lastruccia 13, 50019 Sesto F.no (FI), Italy
| | - Franca M. Cordero
- Dipartimento di Chimica Organica “Ugo Schiff”, Laboratorio di Progettazione, Sintesi e Studio di Eterocicli Biologicamente Attivi - HeteroBioLab, Università degli Studi di Firenze, via della Lastruccia 13, 50019 Sesto F.no (FI), Italy
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Kulkarni NA, Yao CF, Chen K. On the scope of diastereoselective allylation of various chiral glyoxylic oxime ethers with allyltributylstannane in the presence of a Lewis acid and triallylaluminum. Tetrahedron 2007. [DOI: 10.1016/j.tet.2007.05.091] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/23/2022]
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17
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Ghorai MK, Das K, Kumar A. A convenient synthetic route to enantiopure N-tosylazetidines from α-amino acids. Tetrahedron Lett 2007. [DOI: 10.1016/j.tetlet.2007.02.033] [Citation(s) in RCA: 36] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/01/2022]
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Couty F, Evano G. AZETIDINE-2-CARBOXYLIC ACID. FROM LILY OF THE VALLEY TO KEY PHARMACEUTICALS. A JUBILEE REVIEW. ORG PREP PROCED INT 2006. [DOI: 10.1080/00304940609356436] [Citation(s) in RCA: 44] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/20/2022]
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19
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Morimoto H, Wiedemann SH, Yamaguchi A, Harada S, Chen Z, Matsunaga S, Shibasaki M. Trichloromethyl Ketones as Synthetically Versatile Donors: Application in Direct Catalytic Mannich-Type Reactions and the Stereoselective Synthesis of Azetidines. Angew Chem Int Ed Engl 2006. [DOI: 10.1002/ange.200600227] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
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20
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Morimoto H, Wiedemann SH, Yamaguchi A, Harada S, Chen Z, Matsunaga S, Shibasaki M. Trichloromethyl Ketones as Synthetically Versatile Donors: Application in Direct Catalytic Mannich-Type Reactions and the Stereoselective Synthesis of Azetidines. Angew Chem Int Ed Engl 2006; 45:3146-50. [PMID: 16596693 DOI: 10.1002/anie.200600227] [Citation(s) in RCA: 66] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Affiliation(s)
- Hiroyuki Morimoto
- Graduate School of Pharmaceutical Sciences, University of Tokyo, Hongo, Bunkyo-ku, Tokyo 113-0033, Japan
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de Talancé VL, Banide E, Bertin B, Comesse S, Kadouri-Puchot C. Synthesis of enantiopure azetidines: a route to new β-amino alcohols. Tetrahedron Lett 2005. [DOI: 10.1016/j.tetlet.2005.09.061] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
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Couty F, Evano G, Vargas-Sanchez M, Bouzas G. Practical Asymmetric Preparation of Azetidine-2-carboxylic Acid. J Org Chem 2005; 70:9028-31. [PMID: 16238345 DOI: 10.1021/jo0515881] [Citation(s) in RCA: 51] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
[reaction: see text] Facile and straightforward syntheses of both enantiomers of azetidine-2-carboxylic acid are described. The syntheses depart from inexpensive chemicals and allow for the production, in five to six steps, of practical quantities of each enantiomer. Synthetic highlights include the construction of the azetidine ring using an intramolecular alkylation and the use of optically active alpha-methylbenzylamine as chiral auxiliary.
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Affiliation(s)
- Francois Couty
- Laboratoire SIRCOB, UMR CNRS 8086, Université de Versailles Saint Quentin en Yvelines, France
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Bentz EL, Goswami R, Moloney MG, Westaway SM. Stereoselective synthesis of conformationally constrained ω-amino acid analogues from pyroglutamic acid. Org Biomol Chem 2005; 3:2872-82. [PMID: 16032366 DOI: 10.1039/b503994k] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Bicyclic lactams derived from pyroglutamic acid provide a useful scaffold for synthesis of conformationally restricted analogues of lysine, ornithine and glutamine, as well as an Ala-Ala dipeptide analogue. Amino alcohol and carboxylic acid derivatives are accessible from a common intermediate. In this strategy, the bicyclic lactam system not only controls, but also facilitates the determination of the stereochemistry of the synthetic intermediates.
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Affiliation(s)
- Emilie L Bentz
- Department of Chemistry, University of Oxford, Chemistry Research Laboratory, Mansfield Road, Oxford, UK
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Bräuner-Osborne H, Bunch L, Chopin N, Couty F, Evano G, Jensen AA, Kusk M, Nielsen B, Rabasso N. Azetidinic amino acids: stereocontrolled synthesis and pharmacological characterization as ligands for glutamate receptors and transporters. Org Biomol Chem 2005; 3:3926-36. [PMID: 16240010 DOI: 10.1039/b509514j] [Citation(s) in RCA: 46] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
A set of ten azetidinic amino acids, that can be envisioned as C-4 alkyl substituted analogues of trans-2-carboxyazetidine-3-acetic acid (t-CAA) and/or conformationally constrained analogues of (R)- or (S)-glutamic acid (Glu) have been synthesized in a diastereo- and enantiomerically pure form from beta-amino alcohols through a straightforward five step sequence. The key step of this synthesis is an original anionic 4-exo-tet ring closure that forms the azetidine ring upon an intramolecular Michael addition. This reaction was proven to be reversible and to lead to a thermodynamic distribution of two diastereoisomers that were easily separated and converted in two steps into azetidinic amino acids. Azetidines 35-44 were characterized in binding studies on native ionotropic Glu receptors and in functional assays at cloned metabotropic receptors mGluR1, 2 and 4, representing group I, II and III mGlu receptors, respectively. Furthermore, azetidine analogues 35, 36, and 40 were also characterized as potential ligands at the glutamate transporter subtypes EAAT1-3 in the FLIPR Membrane Potential (FMP) assay. The (2R)-azetidines 35, 37, 39, 41 and 43 were inactive in iGlu, mGlu and EAAT assays, whereas a marked change in the pharmacological profile at the iGlu receptors was observed when a methyl group was introduced in the C-4 position, compound 36 versus t-CAA. At EAAT1-3, compound 35 was inactive, whereas azetidines 36 and 40 were both identified as inhibitors and showed selectivity for the EAAT2 subtype.
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Affiliation(s)
- Hans Bräuner-Osborne
- Department of Medicinal Chemistry, Danish University of Pharmaceutical Sciences, Universitetsparken 2, DK-2100, Copenhagen, Denmark
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Enders D, Gries J, Kim ZS. Asymmetric Synthesis of 2-Mono- and 2,3-trans-Disubstituted Azetidines. European J Org Chem 2004. [DOI: 10.1002/ejoc.200400473] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
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26
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Synthesis of enantiopure azetidine 2-carboxylic acids and their incorporation into peptides. ACTA ACUST UNITED AC 2003. [DOI: 10.1016/s0957-4166(03)00493-2] [Citation(s) in RCA: 39] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
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Abstract
The structure and stereochemistry of polyoximic acid, a degradation product of polyoxins, was originally designated as trans-3-ethylidene-L-azetidine-2-carboxylic acid. However, total synthesis revealed that the correct structure was in fact cis-3-ethylidene-L-azetidine-2-carboxylic acid, which was confirmed by X-ray crystallography. The synthesis of the trans-isomer was also done and its identity was confirmed by X-ray analysis as well. The key step for constructing the four-membered ring was a rhodium catalyzed carbenoid insertion into the NH bond of a beta-amino acid derivative. The stereoselectivity of the exo-double bond was controlled by conducting a Horner-Emmons-Wadsworth or a Wittig reaction to generate the trans- and cis-isomers, respectively. Weinreb's amide was used as a latent methyl group for the separation of trans and cis mixtures. The double bond stereochemistry of polyoximic acid in the parent polyoxin was also confirmed to be cis by extensive 2D NMR studies.Key words: diazoinsertion, azetidine, olefination.
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