1
|
Bushkov NS, Rumyantsev AV, Zhizhin AA, Strelkova TV, Novikov RA, Gutsul EI, Takazova RU, Kitaeva DK, Ustynyuk NA, Zhizhko PA, Zarubin DN. Tungsten Oxide Dispersed on Silica as Robust and Readily Available Oxo/Imido Heterometathesis Catalyst. Chempluschem 2024; 89:e202400029. [PMID: 38589286 DOI: 10.1002/cplu.202400029] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/13/2024] [Revised: 04/04/2024] [Accepted: 04/08/2024] [Indexed: 04/10/2024]
Abstract
Continuing our investigation of catalytic oxo/imido heterometathesis as novel water-free method for C=N bond construction, we report here the application of classical transition metal oxides dispersed on silica (MOx/SiO2, M=V, Mo, W) as cheap, robust and readily available alternative to the catalysts prepared via Surface Organometallic Chemistry (SOMC). The oxide materials demonstrated activity in heterometathetical imidation of ketones, WO3/SiO2 being the most efficient. We also describe a new well-defined supported W imido complex (≡SiO)W(=NMes)2(Me2Pyr) (Mes=2,4,6-Me3C6H2, Me2Pyr=2,5-dimethylpyrrolyl) and characterize it with SOMC protocols, which allowed us to identify the position of W on the oxo/imido heterometathesis activity scale (Mo
Collapse
Affiliation(s)
- Nikolai S Bushkov
- A. N. Nesmeyanov Institute of Organoelement Compounds, Russian Academy of Sciences, Vavilov str., 28, 119334, Moscow, Russia
| | - Andrey V Rumyantsev
- A. N. Nesmeyanov Institute of Organoelement Compounds, Russian Academy of Sciences, Vavilov str., 28, 119334, Moscow, Russia
- Chemistry Department, Moscow State University, Vorob'evy Gory, 1, 119992, Moscow, Russia
| | - Anton A Zhizhin
- A. N. Nesmeyanov Institute of Organoelement Compounds, Russian Academy of Sciences, Vavilov str., 28, 119334, Moscow, Russia
| | - Tatyana V Strelkova
- A. N. Nesmeyanov Institute of Organoelement Compounds, Russian Academy of Sciences, Vavilov str., 28, 119334, Moscow, Russia
| | - Roman A Novikov
- N. D. Zelinsky Institute of Organic Chemistry, Russian Academy of Sciences, Leninsky prosp., 47, 119991, Moscow, Russia
| | - Evgenii I Gutsul
- A. N. Nesmeyanov Institute of Organoelement Compounds, Russian Academy of Sciences, Vavilov str., 28, 119334, Moscow, Russia
| | - Rina U Takazova
- A. N. Nesmeyanov Institute of Organoelement Compounds, Russian Academy of Sciences, Vavilov str., 28, 119334, Moscow, Russia
| | - Dinara K Kitaeva
- A. N. Nesmeyanov Institute of Organoelement Compounds, Russian Academy of Sciences, Vavilov str., 28, 119334, Moscow, Russia
| | - Nikolai A Ustynyuk
- A. N. Nesmeyanov Institute of Organoelement Compounds, Russian Academy of Sciences, Vavilov str., 28, 119334, Moscow, Russia
| | - Pavel A Zhizhko
- A. N. Nesmeyanov Institute of Organoelement Compounds, Russian Academy of Sciences, Vavilov str., 28, 119334, Moscow, Russia
| | - Dmitry N Zarubin
- A. N. Nesmeyanov Institute of Organoelement Compounds, Russian Academy of Sciences, Vavilov str., 28, 119334, Moscow, Russia
| |
Collapse
|
2
|
Lu J, Huang L, Liang H, Wang Z, Kato T, Liu Y, Maruoka K. Asymmetric Phase-Transfer Alkylation of Readily Available Aryl Aldehyde Schiff Bases of Amino Acid Ethyl Esters. Org Lett 2024; 26:4163-4167. [PMID: 38289671 DOI: 10.1021/acs.orglett.3c04290] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/25/2024]
Abstract
Asymmetric phase-transfer alkylation of the N-(arylmethylene)-α-alkylamino acid ethyl esters and N-(arylmethylene)glycine ethyl esters was found to be catalyzed by the (R)- or (S)-Simplified Maruoka Catalyst with high efficiency and excellent enantioselectivity. This approach was successfully applied to the enantioselective formal synthesis of the angiotensin II type 2 receptor (AT2R) antagonists Olodanrigan and LX9211, and the practical aspect is demonstrated by the kilogram-scale synthesis of a key intermediate for the synthesis of LX9211.
Collapse
Affiliation(s)
- Jinying Lu
- School of Chemical Engineering and Light Industry, Guangdong University of Technology, Guangzhou 510006, China
- Guangdong Provincial Key Laboratory of Plant Resources Biorefinery, Guangdong University of Technology, Guangzhou 510006, China
| | - Lei Huang
- School of Chemical Engineering and Light Industry, Guangdong University of Technology, Guangzhou 510006, China
- Guangdong Provincial Key Laboratory of Plant Resources Biorefinery, Guangdong University of Technology, Guangzhou 510006, China
| | - Huatai Liang
- School of Chemical Engineering and Light Industry, Guangdong University of Technology, Guangzhou 510006, China
- Guangdong Provincial Key Laboratory of Plant Resources Biorefinery, Guangdong University of Technology, Guangzhou 510006, China
| | - Zhe Wang
- School of Chemical Engineering and Light Industry, Guangdong University of Technology, Guangzhou 510006, China
- Guangdong Provincial Key Laboratory of Plant Resources Biorefinery, Guangdong University of Technology, Guangzhou 510006, China
| | - Terumasa Kato
- School of Chemical Engineering and Light Industry, Guangdong University of Technology, Guangzhou 510006, China
- Guangdong Provincial Key Laboratory of Plant Resources Biorefinery, Guangdong University of Technology, Guangzhou 510006, China
- Laboratory of Organocatalytic Chemistry, Graduate School of Pharmaceutical Sciences, Kyoto University, Sakyo, Kyoto 606-8501, Japan
| | - Yan Liu
- School of Chemical Engineering and Light Industry, Guangdong University of Technology, Guangzhou 510006, China
- Guangdong Provincial Key Laboratory of Plant Resources Biorefinery, Guangdong University of Technology, Guangzhou 510006, China
| | - Keiji Maruoka
- School of Chemical Engineering and Light Industry, Guangdong University of Technology, Guangzhou 510006, China
- Guangdong Provincial Key Laboratory of Plant Resources Biorefinery, Guangdong University of Technology, Guangzhou 510006, China
- Laboratory of Organocatalytic Chemistry, Graduate School of Pharmaceutical Sciences, Kyoto University, Sakyo, Kyoto 606-8501, Japan
| |
Collapse
|
3
|
Derrien B, Leblanc K, Evanno L, Drège E. Enantioselective Total Synthesis of the Neurotoxin Caramboxin. J Org Chem 2024; 89:6489-6493. [PMID: 38607991 DOI: 10.1021/acs.joc.4c00541] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 04/14/2024]
Abstract
Herein, we report the first and efficient asymmetric total synthesis of the neurotoxin (-)-caramboxin. The key to success is the creation of a stereogenic center by using enantioselective catalytic phase-transfer α-alkylation of glycine imines, affording this unusual α-amino acid in good yields and up to 99% ee. This work validates the S configuration of the natural product.
Collapse
Affiliation(s)
- Benoit Derrien
- CNRS, BioCIS, Université Paris-Saclay, Orsay 91400, France
| | - Karine Leblanc
- CNRS, BioCIS, Université Paris-Saclay, Orsay 91400, France
| | - Laurent Evanno
- CNRS, BioCIS, Université Paris-Saclay, Orsay 91400, France
| | | |
Collapse
|
4
|
Pecchini P, Fochi M, Bartoccini F, Piersanti G, Bernardi L. Enantioselective organocatalytic strategies to access noncanonical α-amino acids. Chem Sci 2024; 15:5832-5868. [PMID: 38665517 PMCID: PMC11041364 DOI: 10.1039/d4sc01081g] [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: 02/15/2024] [Accepted: 03/23/2024] [Indexed: 04/28/2024] Open
Abstract
Organocatalytic asymmetric synthesis has evolved over the years and continues to attract the interest of many researchers worldwide. Enantiopure noncanonical amino acids (ncAAs) are valuable building blocks in organic synthesis, medicinal chemistry, and chemical biology. They are employed in the elaboration of peptides and proteins with enhanced activities and/or improved properties compared to their natural counterparts, as chiral catalysts, in chiral ligand design, and as chiral building blocks for asymmetric syntheses of complex molecules, including natural products. The linkage of ncAA synthesis and enantioselective organocatalysis, the subject of this perspective, tries to imitate the natural biosynthetic process. Herein, we present contemporary and earlier developments in the field of organocatalytic activation of simple feedstock materials, providing potential ncAAs with diverse side chains, unique three-dimensional structures, and a high degree of functionality. These asymmetric organocatalytic strategies, useful for forging a wide range of C-C, C-H, and C-N bonds and/or combinations thereof, vary from classical name reactions, such as Ugi, Strecker, and Mannich reactions, to the most advanced concepts such as deracemisation, transamination, and carbene N-H insertion. Concurrently, we present some interesting mechanistic studies/models, providing information on the chirality transfer process. Finally, this perspective highlights, through the diversity of the amino acids (AAs) not selected by nature for protein incorporation, the most generic modes of activation, induction, and reactivity commonly used, such as chiral enamine, hydrogen bonding, Brønsted acids/bases, and phase-transfer organocatalysis, reflecting their increasingly important role in organic and applied chemistry.
Collapse
Affiliation(s)
- Pietro Pecchini
- Department of Industrial Chemistry "Toso Montanari", Center for Chemical Catalysis C3 & INSTM RU Bologna V. Gobetti 85 40129 Bologna Italy
| | - Mariafrancesca Fochi
- Department of Industrial Chemistry "Toso Montanari", Center for Chemical Catalysis C3 & INSTM RU Bologna V. Gobetti 85 40129 Bologna Italy
| | - Francesca Bartoccini
- Department of Biomolecular Sciences, University of Urbino Carlo Bo Piazza Rinascimento 6 61029 Urbino PU Italy
| | - Giovanni Piersanti
- Department of Biomolecular Sciences, University of Urbino Carlo Bo Piazza Rinascimento 6 61029 Urbino PU Italy
| | - Luca Bernardi
- Department of Industrial Chemistry "Toso Montanari", Center for Chemical Catalysis C3 & INSTM RU Bologna V. Gobetti 85 40129 Bologna Italy
| |
Collapse
|
5
|
Zhang Y, Vanderghinste J, Wang J, Das S. Challenges and recent advancements in the synthesis of α,α-disubstituted α-amino acids. Nat Commun 2024; 15:1474. [PMID: 38368416 PMCID: PMC10874380 DOI: 10.1038/s41467-024-45790-2] [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: 06/13/2023] [Accepted: 02/01/2024] [Indexed: 02/19/2024] Open
Abstract
α,α-Disubstituted α-amino acids (α-AAs) have improved properties compared to other types of amino acids. They serve as modifiers of peptide conformation and as precursors of bioactive compounds. Therefore, it has been a long-standing goal to construct this highly valuable scaffold efficiently in organic synthesis and drug discovery. However, access to α,α-disubstituted α-AAs is highly challenging and largely unexplored due to their steric constraints. To overcome these, remarkable advances have been made in the last decades. Emerging strategies such as synergistic enantioselective catalysis, visible-light-mediated photocatalysis, metal-free methodologies and CO2 fixation offer new avenues to access the challenging synthesis of α,α-disubstituted α-AAs and continuously bring additional contributions to this field. This review article aims to provide an overview of the recent advancements since 2015 and discuss existing challenges for the synthesis of α,α-disubstituted α-AAs and their derivatives.
Collapse
Affiliation(s)
- Yu Zhang
- Shanghai Frontiers Science Center for Chinese Medicine Chemical Biology, Institute of Interdisciplinary Integrative Medicine Research, Shanghai University of Traditional Chinese Medicine, No. 1200, Cailun Road, 201203, Shanghai, China.
- Department of Chemistry, University of Antwerp, Groenenborgerlaan 171, 2020, Antwerpen, Belgium.
| | - Jaro Vanderghinste
- Department of Chemistry, University of Antwerp, Groenenborgerlaan 171, 2020, Antwerpen, Belgium
| | - Jinxin Wang
- Shanghai Frontiers Science Center for Chinese Medicine Chemical Biology, Institute of Interdisciplinary Integrative Medicine Research, Shanghai University of Traditional Chinese Medicine, No. 1200, Cailun Road, 201203, Shanghai, China
| | - Shoubhik Das
- Department of Chemistry, University of Antwerp, Groenenborgerlaan 171, 2020, Antwerpen, Belgium.
- Department of Chemistry, University of Bayreuth, Bayreuth, Germany.
| |
Collapse
|
6
|
Rodríguez-Flórez LV, González-Marcos M, García-Mingüens E, Retamosa MDG, Kawase M, Selva E, Sansano JM. Phosphine Catalyzed Michael-Type Additions: The Synthesis of Glutamic Acid Derivatives from Arylidene- α-amino Esters. Molecules 2024; 29:342. [PMID: 38257255 PMCID: PMC10820836 DOI: 10.3390/molecules29020342] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/12/2023] [Revised: 12/28/2023] [Accepted: 01/07/2024] [Indexed: 01/24/2024] Open
Abstract
The reaction of arylidene-α-amino esters with electrophilic alkenes to yield Michael-type addition compounds is optimized using several phosphines as organocatalysts. The transformation is very complicated due to the generation of several final compounds, including those derived from the 1,3-dipolar cycloadditions. For this reason, the selection of the reaction conditions is a very complex task and the slow addition of the acrylic system is very important to complete the process. The study of the variation in the structural components of the starting imino ester is performed as well as the expansion of other electron-poor alkenes. The crude products have a purity higher than 90% in most cases without any purification. A plausible mechanism is detailed based on the bibliography and the experimental results. The synthesis of pyroglutamate entities, after the reduction of the imino group and cyclization, is performed in high yields. In addition, the hydrolysis of the imino group, under acidic media, represents a direct access to glutamate surrogates.
Collapse
Affiliation(s)
- Lesly V. Rodríguez-Flórez
- Departamento de Química Orgánica, Centro de Innovación en Química Avanzada (ORFEO-CINQA) and Instituto de Síntesis Orgánica, Universidad de Alicante, Ctra. Alicante-San Vicente s/n, 03080 Alicante, Spain
| | - María González-Marcos
- Departamento de Química Orgánica, Centro de Innovación en Química Avanzada (ORFEO-CINQA) and Instituto de Síntesis Orgánica, Universidad de Alicante, Ctra. Alicante-San Vicente s/n, 03080 Alicante, Spain
| | - Eduardo García-Mingüens
- Medalchemy, S. L. Ancha de Castelar, 46-48, entlo. A. San Vicente del Raspeig, 03690 Alicante, Spain
| | - María de Gracia Retamosa
- Departamento de Química Orgánica, Centro de Innovación en Química Avanzada (ORFEO-CINQA) and Instituto de Síntesis Orgánica, Universidad de Alicante, Ctra. Alicante-San Vicente s/n, 03080 Alicante, Spain
| | - Misa Kawase
- Departamento de Química Orgánica, Centro de Innovación en Química Avanzada (ORFEO-CINQA) and Instituto de Síntesis Orgánica, Universidad de Alicante, Ctra. Alicante-San Vicente s/n, 03080 Alicante, Spain
| | - Elisabet Selva
- Medalchemy, S. L. Ancha de Castelar, 46-48, entlo. A. San Vicente del Raspeig, 03690 Alicante, Spain
| | - José M. Sansano
- Departamento de Química Orgánica, Centro de Innovación en Química Avanzada (ORFEO-CINQA) and Instituto de Síntesis Orgánica, Universidad de Alicante, Ctra. Alicante-San Vicente s/n, 03080 Alicante, Spain
| |
Collapse
|
7
|
Mąkosza M, Fedoryński M. Chlorine in an Organic Molecule, a Universal Promoter-Workhorse-Of Reactions. Molecules 2023; 28:7957. [PMID: 38138446 PMCID: PMC10745902 DOI: 10.3390/molecules28247957] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/25/2023] [Revised: 11/26/2023] [Accepted: 12/01/2023] [Indexed: 12/24/2023] Open
Abstract
Due to the electronic configuration of the atom and charge of the nucleus, the chlorine in organic molecules can exert a variety of effects. It can depart as a chloride anion in the process of substitution and elimination, facilitates the abstraction of protons and stabilizes generated carbanions, exerts moderate stabilizing effect of carbenes, carbocations and radicals. There are frequent cases where chlorine substituent promotes more than one transformation. These rich effects of chlorine substituent will be illustrated by examples of our work.
Collapse
Affiliation(s)
- Mieczysław Mąkosza
- Institute of Organic Chemistry, Polish Academy of Sciences, Kasprzaka 44/52, 01-224 Warsaw, Poland
| | - Michał Fedoryński
- Faculty of Chemistry, Warsaw University of Technology, Noakowskiego 3, 00-664 Warsaw, Poland
| |
Collapse
|
8
|
Kratena N, Draskovits M, Biedermann N, Oburger E, Stanetty C. Total synthesis of [ 13 C 2 ]-labeled phytosiderophores of the mugineic and avenic acid families. J Labelled Comp Radiopharm 2023; 66:428-434. [PMID: 37755147 DOI: 10.1002/jlcr.4064] [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: 07/07/2023] [Revised: 09/06/2023] [Accepted: 09/08/2023] [Indexed: 09/28/2023]
Abstract
We, herein, report the synthesis of 13 C2 -labeled natural products from the mugineic acid and avenic acid family. These phytosiderophores ("plant iron carriers") are built up from non-proteinogenic amino acids and play a key role in micronutrient uptake in gramineous plants. In this work, two central building blocks are prepared from labeled starting materials (13 C2 -bromoacetic acid, 13 C2 -glycine) and further employed in our recently reported divergent, branched synthetic strategy delivering eight isotopically labeled phytosiderophores. The required labeled building blocks (13 C2 -l-allylglycine and a related hydroxylated derivative) were prepared via enantioselective phase-transfer catalysis and enantio- and diastereoselective aldol condensation with a chiral auxiliary, respectively, both potentially valuable themselves for other synthetic routes toward labeled (natural) products.
Collapse
Affiliation(s)
- Nicolas Kratena
- Institute of Applied Synthetic Chemistry, TU Wien, Vienna, Austria
| | | | - Nina Biedermann
- Institute of Applied Synthetic Chemistry, TU Wien, Vienna, Austria
| | - Eva Oburger
- Institute of Soil Research, BOKU Vienna, Tulln, Austria
| | | |
Collapse
|
9
|
Ričko S, Bitsch RS, Kaasik M, Otevřel J, Højgaard Madsen M, Keimer A, Jørgensen KA. Enantioconvergent 6π Electrocyclization Enabled by Photoredox Racemization. J Am Chem Soc 2023; 145:20913-20926. [PMID: 37753541 DOI: 10.1021/jacs.3c06227] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 09/28/2023]
Abstract
This study presents a novel photoredox-enabled enantioconvergent catalytic strategy used to construct chiral 2H-1,3-benzoxazines via an unprecedented oxa-6π electrocyclization utilizing racemic α-substituted glycinates as substrates. The approach leverages a cobalt-based chiral Lewis acid catalyst, which promotes the transformation under thermal or photoredox conditions. While the thermal reaction selectively converts only the (S)-configured glycinates into enantioenriched 2H-1,3-benzoxazines (up to 96:4 e.r.), the addition of 0.5 mol % of a commercially available iridium photocatalyst under visible light irradiation transforms the reaction into an enantioconvergent process. Detailed mechanistic and time course studies of optically pure α-deuterated substrates revealed the presence of an enantiospecific kinetic isotope effect, which helped to clarify the role of both the photo- and chiral Lewis acid catalyst in the reaction sequence. In this dual catalytic system, the photocatalyst promotes a dynamic interconversion between the substrate enantiomers─a process not accessible via ground-state chemistry─while the chiral Lewis acid selectively transforms only the (S)-configured substrates. Further mechanistic evidence for the proposed mechanism is provided by linear free energy relationship analysis, which suggests that the stereodetermining step involves a 6π electrocyclization under both thermal and photoredox conditions.
Collapse
Affiliation(s)
- Sebastijan Ričko
- Department of Chemistry, Aarhus University, DK-8000 Aarhus C, Denmark
- Aarhus Institute of Advanced Studies, Aarhus University, DK-8000 Aarhus C, Denmark
| | - René Slot Bitsch
- Department of Chemistry, Aarhus University, DK-8000 Aarhus C, Denmark
| | - Mikk Kaasik
- Department of Chemistry, Aarhus University, DK-8000 Aarhus C, Denmark
| | - Jan Otevřel
- Department of Chemistry, Aarhus University, DK-8000 Aarhus C, Denmark
| | | | - Anna Keimer
- Department of Chemistry, Aarhus University, DK-8000 Aarhus C, Denmark
| | | |
Collapse
|
10
|
Stockhammer L, Craik R, Monkowius U, Cordes DB, Smith AD, Waser M. Isothiourea-Catalyzed Enantioselective Functionalisation of Glycine Schiff Base Aryl Esters via 1,6- and 1,4-Additions. CHEMISTRYEUROPE 2023; 1:e202300015. [PMID: 38882579 PMCID: PMC7616101 DOI: 10.1002/ceur.202300015] [Citation(s) in RCA: 6] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 02/28/2023] [Indexed: 06/18/2024]
Abstract
The enantioselective α-functionalisation of glycine Schiff base aryl esters through isothiourea catalysis is successfully demonstrated for 1,6-additions to para-quinone methides (21 examples, up to 95:5 dr and 96:4 er) and 1,4-additions to methylene substituted dicarbonyl or disulfonyl Michael acceptors (17 examples, up to 98:2 er). This nucleophilic organocatalysis approach gives access to a range of α-functionalised α-amino acid derivatives and further transformations of the activated aryl ester group provide a straightforward entry to advanced amino acid-based esters, amides or thioesters.
Collapse
Affiliation(s)
- Lotte Stockhammer
- Institute of Organic Chemistry, Johannes Kepler University Linz, Altenbergerstrasse 69, 4040 Linz (Austria)
| | - Rebecca Craik
- EaStCHEM, School of Chemistry, University of St Andrews, KY16 9ST St Andrews, Fife, (UK)
| | - Uwe Monkowius
- School of Education, Chemistry, Johannes Kepler University Linz, Altenbergerstrasse 69, 4040 Linz (Austria)
| | - David B Cordes
- EaStCHEM, School of Chemistry, University of St Andrews, KY16 9ST St Andrews, Fife, (UK)
| | - Andrew D Smith
- EaStCHEM, School of Chemistry, University of St Andrews, KY16 9ST St Andrews, Fife, (UK)
| | - Mario Waser
- Institute of Organic Chemistry, Johannes Kepler University Linz, Altenbergerstrasse 69, 4040 Linz (Austria)
| |
Collapse
|
11
|
Meena K, Kumar Baroliya P. Synthesis, Characterization, Antimicrobial and Antimalarial Activities of Azines Based Schiff Bases and their Pd(II) Complexes. Chem Biodivers 2023; 20:e202300158. [PMID: 37272557 DOI: 10.1002/cbdv.202300158] [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: 02/02/2023] [Revised: 06/03/2023] [Accepted: 06/05/2023] [Indexed: 06/06/2023]
Abstract
Herein, we report synthesis, characterization, antimicrobial and antimalarial activities of azines Schiff base ligands (L1 -L4 ) and their palladium (II) complexes (C1 -C4 ) of [Pd(L)(OAc)2 ] type. The azine ligands (L1 -L4 ) were prepared by condensation of carbonyl compounds with hydrazine hydrate and their complexes by the reaction of palladium acetate with L1 -L4 ligands in 1 : 1 molar ratio. The prepared ligands and their complexes were characterized by spectral characterization using 1 H &13 C-NMR, FT-IR and mass spectral studies, which revealed that the ligands coordinates via azomethine nitrogen and heteroatom or aryl carbon with palladium. Moreover, Schiff bases and their palladium (II) complexes have been screened for their antibacterial (S. aureus, B. subtillis, and S. typhi, P. aeruginosa), antifungal (C. albicans, A. niger, and A. clavatus) and antimalarial (P. falciparum) activities. The Schiff base L4 showed good results for antibacterial against S. aureus (MIC, 50 μg/mL) and antimalarial against P. falciparum (IC50 , 0.83 μg/mL). The complex C1 showed best antibacterial activity (MIC, 62.5 μg/mL) against S. typhi and the complex C4 exhibited remarkable antimalarial activity (IC50 , 0.42 μg/mL) among the tested compounds. Thus, azines based ligands and their Pd complexes can be good antimicrobial and antimalarial agents if explored further.
Collapse
Affiliation(s)
- Kiran Meena
- Department of Chemistry, Mohanlal Sukhadia University, Udaipur, 313001, India
| | | |
Collapse
|
12
|
Espinoza-Hicks JC, Chavez-Flores D, Zaragoza-Galan G, Camacho-Davila AA. Stereoselective synthesis of S-norvaline and related amino acids through a common intermediate. Amino Acids 2023:10.1007/s00726-023-03289-y. [PMID: 37294378 DOI: 10.1007/s00726-023-03289-y] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/04/2023] [Accepted: 06/02/2023] [Indexed: 06/10/2023]
Abstract
A divergent, enantioselective synthetic strategy is reported to produce the non-proteinogenic, biologically active natural amino acids norvaline, 5-hydroxy-4-oxo-L-norvaline, and ɣ-oxonorvaline. These were synthesized in good yields (45-75%) from the common starting material (S)-allylglycine obtained by asymmetric transfer allylation of glycine Schiff base using the Corey catalyst derived from cinchonidine in more than 97% enantiomeric excess.
Collapse
Affiliation(s)
- José C Espinoza-Hicks
- Facultad de Ciencias Químicas, Universidad Autónoma de Chihuahua, Campus Universitario 2, 31115, Chihuahua, Chih, Mexico
| | - David Chavez-Flores
- Facultad de Ciencias Químicas, Universidad Autónoma de Chihuahua, Campus Universitario 2, 31115, Chihuahua, Chih, Mexico
| | - Gerardo Zaragoza-Galan
- Facultad de Ciencias Químicas, Universidad Autónoma de Chihuahua, Campus Universitario 2, 31115, Chihuahua, Chih, Mexico
| | - Alejandro A Camacho-Davila
- Facultad de Ciencias Químicas, Universidad Autónoma de Chihuahua, Campus Universitario 2, 31115, Chihuahua, Chih, Mexico.
| |
Collapse
|
13
|
Laboratory Scale Continuous Flow Systems for the Enantioselective Phase Transfer Catalytic Synthesis of Quaternary Amino Acids. Molecules 2023; 28:molecules28031002. [PMID: 36770669 PMCID: PMC9920360 DOI: 10.3390/molecules28031002] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/21/2022] [Revised: 01/11/2023] [Accepted: 01/17/2023] [Indexed: 01/20/2023] Open
Abstract
The use of stereoselective phase-transfer catalysis as a reliable method for the enantioselective synthesis of optically active α-amino acid derivatives using achiral Schiff base esters has been well-developed in batch in the last 40 years. Recently, continuous flow technology has become of great interest in the academy and industry, since it offers safer process operating conditions and higher efficiency compared to a traditional batch processing. Herein, we wish to report the first example of enantioselective phase transfer benzylation of alanine Schiff base ester, under continuous flow conditions. Two different methodologies were investigated: a liquid-solid phase transfer catalytic benzylation using a packed-bed reactor and a liquid-liquid phase transfer catalytic benzylation in continuous stirred-tank reactors. Liquid-liquid phase transfer process in flow showed slightly better productivity than the batch process, while solid-liquid phase transfer benzylation proved much more advantageous in terms of productivity and space-time yield. Furthermore, continuous flow system allowed the isolation of benzylated product without any work up, with a significant simplification of the process. In both cases, phase transfer asymmetric benzylation promoted by Maruoka catalyst demonstrated high enantioselectivity of target quaternary amino ester in flow, up to 93% ee.
Collapse
|
14
|
Dmitrieva AV, Levitskiy OA, Grishin YK, Magdesieva TV. A new oxidatively stable ligand for the chiral functionalization of amino acids in Ni(II)-Schiff base complexes. Beilstein J Org Chem 2023; 19:566-574. [PMID: 37153644 PMCID: PMC10155621 DOI: 10.3762/bjoc.19.41] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/17/2023] [Accepted: 04/14/2023] [Indexed: 05/10/2023] Open
Abstract
A new oxidatively stable (S)-N-benzylproline-derived ligand ((S)-N-(2-benzoyl-5-tert-butylphenyl)-1-benzylpyrrolidine-2-carboxamide) and its Ni(II)-Schiff base complexes formed of glycine, serine, and dehydroalanine are reported. A bulky tert-butyl substituent in the phenylene fragment precludes unwanted oxidative dimerization of the Schiff base complex, making it suitable for targeted electrochemically induced oxidative modification of the amino acid side chain. Experimental and DFT studies showed that the additional tert-butyl group increases the dispersion interactions in the Ni coordination environment making the complexes more conformationally rigid and provides a higher level of thermodynamically controlled stereoselectivity as compared to the parent Belokon complex. Additionally, functionalization with the tert-butyl group significantly enhances the reactivity of the deprotonated glycine complex towards electrophiles as compared to the anionic species formed from the original Belokon complex. Solubility of the t-Bu-containing ligand and its Schiff base complexes is increased, facilitating scaling-up the reaction procedure and isolation of the functionalized amino acid.
Collapse
Affiliation(s)
- Alena V Dmitrieva
- Lomonosov Moscow State University, Dept. of Chemistry, Leninskie Gory 1/3, Moscow 119991, Russia
| | - Oleg A Levitskiy
- Lomonosov Moscow State University, Dept. of Chemistry, Leninskie Gory 1/3, Moscow 119991, Russia
| | - Yuri K Grishin
- Lomonosov Moscow State University, Dept. of Chemistry, Leninskie Gory 1/3, Moscow 119991, Russia
| | - Tatiana V Magdesieva
- Lomonosov Moscow State University, Dept. of Chemistry, Leninskie Gory 1/3, Moscow 119991, Russia
| |
Collapse
|
15
|
Elucidation for coordination features of N-(benzothiazol-2-yl)-3-oxo-3-(2-(3-phenylallylidene)hydrazineyl)propanamide on Co2+, Ni2+and Cu2+: Structural description, DFT geometry optimization, cyclic voltammetry and biological inspection. J Mol Liq 2022. [DOI: 10.1016/j.molliq.2022.120613] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
|
16
|
Young HA, Proulx C. On-resin Cα-functionalization of N-arylglycinyl peptides with boronic acids. Org Biomol Chem 2022; 20:6245-6249. [PMID: 35616496 DOI: 10.1039/d2ob00524g] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
A late-stage α-C-H functionalization reaction of resin-bound, electron-rich N-aryl peptides with boronic acid nucleophiles under mild conditions is reported. We explore the impact of the N-arylglycinyl peptide structure on reactivity, and present a scope of the optimized reaction where both the peptide sequence and nature of boronic acid derivatives are varied.
Collapse
Affiliation(s)
- Hailey A Young
- Department of Chemistry, North Carolina State University, Raleigh, NC 27695-8204, USA.
| | - Caroline Proulx
- Department of Chemistry, North Carolina State University, Raleigh, NC 27695-8204, USA.
| |
Collapse
|
17
|
Milewska KD, Malins LR. Synthesis of Amino Acid α-Thioethers and Late-Stage Incorporation into Peptides. Org Lett 2022; 24:3680-3685. [DOI: 10.1021/acs.orglett.2c01297] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Karen D. Milewska
- Research School of Chemistry, Australian National University, Canberra, ACT 2601, Australia
| | - Lara R. Malins
- Research School of Chemistry, Australian National University, Canberra, ACT 2601, Australia
| |
Collapse
|
18
|
Haider V, Zebrowski P, Michalke J, Monkowius U, Waser M. Enantioselective organocatalytic syntheses of α-selenated α- and β-amino acid derivatives. Org Biomol Chem 2022; 20:824-830. [PMID: 35015015 PMCID: PMC8790592 DOI: 10.1039/d1ob02235k] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/15/2021] [Accepted: 01/03/2022] [Indexed: 12/22/2022]
Abstract
Selenium-containing amino acids are valuable targets but methods for the stereoselective α-selenation of simple amino acid precursors are rare. We herein report the enantioselective electrophilic α-selenation of azlactones (masked α-amino acid derivatives) and isoxazolidin-5-ones (masked β-amino acids) using Cinchona alkaloids as easily accessible organocatalysts. A variety of differently substituted derivatives was accessed with reasonable levels of enantioselectivities and further studies concerning the stability and suitability of these compounds for further manipulations have been carried out as well.
Collapse
Affiliation(s)
- Victoria Haider
- Institute of Organic Chemistry, Johannes Kepler University Linz, Altenbergerstrasse 69, 4040 Linz, Austria.
| | - Paul Zebrowski
- Institute of Organic Chemistry, Johannes Kepler University Linz, Altenbergerstrasse 69, 4040 Linz, Austria.
| | - Jessica Michalke
- Institute of Catalysis, Johannes Kepler University Linz, Altenbergerstrasse 69, 4040 Linz, Austria
| | - Uwe Monkowius
- School of Education, Chemistry, Johannes Kepler University Linz, Altenbergerstrasse 69, 4040 Linz, Austria
| | - Mario Waser
- Institute of Organic Chemistry, Johannes Kepler University Linz, Altenbergerstrasse 69, 4040 Linz, Austria.
| |
Collapse
|
19
|
Ikeda T, Ochiishi H, Yoshida M, Yazaki R, Ohshima T. Catalytic Dehydrogenative β-Alkylation of Amino Acid Schiff Bases with Hydrocarbon. Org Lett 2022; 24:369-373. [PMID: 34918939 DOI: 10.1021/acs.orglett.1c04042] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
A synthetic method for the synthesis of a highly congested α,β-dehydroamino acid through the β-C-H bond activation of an amino acid Schiff base is described. Abundant hydrocarbon feedstock could be used as an alkylating reagent to afford an α,β-dehydroamino acid bearing a quaternary carbon at the γ-position with an exclusively (Z)-geometry. Notably, a tetrasubstituted olefin could be constructed from saturated starting materials. The transformation of the synthesized α,β-dehydroamino acid into unnatural α-amino acid derivatives was also demonstrated.
Collapse
Affiliation(s)
- Tetsu Ikeda
- Graduate School of Pharmaceutical Sciences, Kyushu University, Fukuoka 812-8582, Japan
| | - Haruka Ochiishi
- Graduate School of Pharmaceutical Sciences, Kyushu University, Fukuoka 812-8582, Japan
| | - Mana Yoshida
- Graduate School of Pharmaceutical Sciences, Kyushu University, Fukuoka 812-8582, Japan
| | - Ryo Yazaki
- Graduate School of Pharmaceutical Sciences, Kyushu University, Fukuoka 812-8582, Japan
| | - Takashi Ohshima
- Graduate School of Pharmaceutical Sciences, Kyushu University, Fukuoka 812-8582, Japan
| |
Collapse
|
20
|
Han J, Lyutenko NV, Sorochinsky AE, Okawara A, Konno H, White S, Soloshonok VA. Tailor-Made Amino Acids in Pharmaceutical Industry: Synthetic Approaches to Aza-Tryptophan Derivatives. Chemistry 2021; 27:17510-17528. [PMID: 34913215 DOI: 10.1002/chem.202102485] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/09/2021] [Accepted: 08/24/2021] [Indexed: 12/22/2022]
Abstract
Over the recent years there has been a noticeable upsurge of interest in aza-analogs of tryptophan which are isosteric to the latter and found numerous applications in medicinal, bioorganic chemistry, and peptide research. In the present review article, five aza-tryptophan derivatives are profiled, including aza-substitution in the positions 2, on the five-membered ring, as well as in positions 4, 5, 6, and 7 on the six-membered ring. A detailed and comprehensive literature overview of the synthetic methods for the preparation of these aza-tryptophans is presented and general facets of the biological properties and most promising applications are discussed.
Collapse
Affiliation(s)
- Jianlin Han
- Jiangsu Co-Innovation Center of Efficient Processing and Utilization of Forest Resources International Innovation Center for Forest Chemicals and Materials College of Chemical Engineering, Nanjing Forestry University, Nanjing, 210037, P. R. China
| | - Nataliya V Lyutenko
- Department of Fine Organic Synthesis V.P. Kukhar Institute of Bioorganic Chemistry and Petrochemistry, The National Academy of Sciences of Ukraine, 1 Murmanska str., Kyiv, 02094, Ukraine
| | - Alexander E Sorochinsky
- Department of Fine Organic Synthesis V.P. Kukhar Institute of Bioorganic Chemistry and Petrochemistry, The National Academy of Sciences of Ukraine, 1 Murmanska str., Kyiv, 02094, Ukraine
| | - Ayaka Okawara
- Graduate School of Science and Engineering, Yamagata University, 4-3-16, Jonan, Yonezawa, Yamagata, 992-8510, Japan
| | - Hiroyuki Konno
- Graduate School of Science and Engineering, Yamagata University, 4-3-16, Jonan, Yonezawa, Yamagata, 992-8510, Japan
| | - Sarah White
- Oakwood Chemical, Inc., 730 Columbia Hwy. N, Estill, SC, 29918, USA
| | - Vadim A Soloshonok
- Department of Organic Chemistry I Faculty of Chemistry, University of the Basque Country UPV/EHU, Paseo Manuel Lardizábal 3, 20018, San Sebastián, Spain.,IKERBASQUE, Basque Foundation for Science, María Díaz de Haro 3, Plaza Bizkaia, 48013, Bilbao, Spain
| |
Collapse
|
21
|
Liu A, Han J, Nakano A, Konno H, Moriwaki H, Abe H, Izawa K, Soloshonok VA. New pharmaceuticals approved by FDA in 2020: Small-molecule drugs derived from amino acids and related compounds. Chirality 2021; 34:86-103. [PMID: 34713503 DOI: 10.1002/chir.23376] [Citation(s) in RCA: 21] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/03/2021] [Revised: 09/09/2021] [Accepted: 09/26/2021] [Indexed: 12/24/2022]
Abstract
Amino acids (AAs) play an important role in the modern health industry as key synthetic precursors for pharmaceuticals, biomaterials, biosensors, and drug delivery systems. Currently, over 30% of small-molecule drugs contain residues of tailor-made AAs or derived from them amino-alcohols and di-amines. In this review article, we profile 12 AA-derived new pharmaceuticals approved by the FDA in 2020. These newly introduced drugs include Tazverik (epithelioid sarcoma), Gemtesa (overactive bladder), Zeposia (multiple sclerosis), Byfavo (induction and maintenance of procedural sedation), Cu 64 dotatate, and Gallium 68 PSMA-11 (both PET imaging), Rimegepant (acute migraine), Zepzelca (lung cancer), Remdesivir (COVID-19), Amisulpride (nausea and vomiting), Setmelanotide (obesity), and Lonafarnib (progeria syndrome). For each compound, we describe the spectrum of biological activity, medicinal chemistry discovery, and synthetic preparation.
Collapse
Affiliation(s)
- Aiyao Liu
- Jiangsu Co-Innovation Center of Efficient Processing and Utilization of Forest Resources, College of Chemical Engineering, Nanjing Forestry University, Nanjing, China
| | - Jianlin Han
- Jiangsu Co-Innovation Center of Efficient Processing and Utilization of Forest Resources, College of Chemical Engineering, Nanjing Forestry University, Nanjing, China
| | - Arina Nakano
- Department of Biological Engineering, Graduate School of Science and Engineering, Yamagata University, Yonezawa, Japan
| | - Hiroyuki Konno
- Department of Biological Engineering, Graduate School of Science and Engineering, Yamagata University, Yonezawa, Japan
| | | | | | | | - Vadim A Soloshonok
- Department of Organic Chemistry I, Faculty of Chemistry, University of the Basque Country UPV/EHU, San Sebastián, Spain.,IKERBASQUE, Basque Foundation for Science, Bilbao, Spain
| |
Collapse
|
22
|
Henry Blackwell J, Harris GR, Smith MA, Gaunt MJ. Modular Photocatalytic Synthesis of α-Trialkyl-α-Tertiary Amines. J Am Chem Soc 2021; 143:15946-15959. [PMID: 34551248 DOI: 10.1021/jacs.1c07402] [Citation(s) in RCA: 13] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022]
Abstract
Molecules displaying an α-trialkyl-α-tertiary amine motif provide access to an important and versatile area of biologically relevant chemical space but are challenging to access through existing synthetic methods. Here, we report an operationally straightforward, multicomponent protocol for the synthesis of a range of functionally and structurally diverse α-trialkyl-α-tertiary amines, which makes use of three readily available components: dialkyl ketones, benzylamines, and alkenes. The strategy relies on the of use visible-light-mediated photocatalysis with readily available Ir(III) complexes to bring about single-electron reduction of an all-alkyl ketimine species to an α-amino radical intermediate; the α-amino radical undergoes Giese-type addition with a variety of alkenes to forge the α-trialkyl-α-tertiary amine center. The mechanism of this process is believed to proceed through an overall redox neutral pathway that involves photocatalytic redox-relay of the imine, generated from the starting amine-ketone condensation, through to an imine-derived product. This is possible because the presence of a benzylic amine component in the intermediate scaffold drives a 1,5-hydrogen atom transfer step after the Giese addition to form a stable benzylic α-amino radical, which is able to close the photocatalytic cycle. These studies detail the evolution of the reaction platform, an extensive investigation of the substrate scope, and preliminary investigation of some of the mechanistic features of this distinct photocatalytic process. We believe this transformation will provide convenient access to previously unexplored α-trialkyl-α-tertiary amine scaffolds that should be of considerable interest to practitioners of synthetic and medicinal chemistry in academic and industrial institutions.
Collapse
Affiliation(s)
- J Henry Blackwell
- Yusuf Hamied Department of Chemistry, University of Cambridge, Lensfield Road, Cambridge CB2 1EW, United Kingdom
| | - Georgia R Harris
- Yusuf Hamied Department of Chemistry, University of Cambridge, Lensfield Road, Cambridge CB2 1EW, United Kingdom
| | - Milo A Smith
- Yusuf Hamied Department of Chemistry, University of Cambridge, Lensfield Road, Cambridge CB2 1EW, United Kingdom
| | - Matthew J Gaunt
- Yusuf Hamied Department of Chemistry, University of Cambridge, Lensfield Road, Cambridge CB2 1EW, United Kingdom
| |
Collapse
|
23
|
Larionov VA, Feringa BL, Belokon YN. Enantioselective "organocatalysis in disguise" by the ligand sphere of chiral metal-templated complexes. Chem Soc Rev 2021; 50:9715-9740. [PMID: 34259242 DOI: 10.1039/d0cs00806k] [Citation(s) in RCA: 19] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
Abstract
Asymmetric catalysis holds a prominent position among the important developments in chemistry during the 20th century. This was acknowledged by the 2001 Nobel Prize in chemistry awarded to Knowles, Noyori, and Sharpless for their development of chiral metal catalysts for organic transformations. The key feature of the catalysts was the crucial role of the chiral ligand and the nature of the metal ions, which promoted the catalytic conversions of the substrates via direct coordination. Subsequently the development of asymmetric organic catalysis opened new avenues to the synthesis of enantiopure compounds, avoiding any use of metal ions. Recently, an alternative approach to asymmetric catalysis emerged that relied on the catalytic functions of the ligands themselves boosted by coordination to metal ions. In other words, in these hybrid chiral catalysts the substrates are activated not by the metal ions but by the ligands. The activation and enantioselective control occurred via well-orchestrated and custom-tailored non-covalent interactions of the substrates with the ligand sphere of chiral metal complexes. In these metal-templated catalysts, the metal served either as a template (a purely structural role), or it constituted the exclusive source of chirality (metal-centred chirality due to the spatial arrangement of achiral or chiral bi-/tridentate ligands around an octahedral metal centre), and/or it increased the Brønsted acidity of the ligands. Although the field is still in its infancy, it represents an inspiring combination of both metal and organic catalysis and holds major unexplored potential to push the frontiers of asymmetric catalysis. Here we present an overview of this emerging field discussing the principles, applications and perspectives on the catalytic use of chiral metal complexes that operate as "organocatalysts in disguise". It has been demonstrated that these chiral metal complexes are efficient and provide high stereoselective control in asymmetric hydrogen bonding catalysis, phase-transfer catalysis, Brønsted acid/base catalysis, enamine catalysis, nucleophilic catalysis, and photocatalysis as well as bifunctional catalysis. Also, many of the catalysts have been identified as highly effective catalysts at remarkably low catalyst loadings. These hybrid systems offer many opportunities in the synthesis of chiral compounds and represent promising alternatives to metal-based and organocatalytic asymmetric transformations.
Collapse
Affiliation(s)
- Vladimir A Larionov
- A. N. Nesmeyanov Institute of Organoelement Compounds of Russian Academy of Sciences, Vavilov Street 28, 119991 Moscow, Russian Federation.
| | | | | |
Collapse
|
24
|
Loro C, Sala R, Penso M, Foschi F. DBU Catalysed Enantioselective Degradative Rearrangement: a Way to Tetrasubstituted 2‐Aryl‐2‐Amino Esters. Adv Synth Catal 2021. [DOI: 10.1002/adsc.202100493] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022]
Affiliation(s)
- Camilla Loro
- Dipartimento di Scienza e Alta Tecnologia Università degli Studi dell'Insubria Via Valleggio 9 IT-20100 Como Italy
| | - Roberto Sala
- Dipartimento di Scienza e Alta Tecnologia Università degli Studi dell'Insubria Via Valleggio 9 IT-20100 Como Italy
| | - Michele Penso
- CNR-Istituto di Scienze e Tecnologie Chimiche “Giulio Natta” (SCITEC) Via Golgi 19 IT-20133 Milano Italy
| | - Francesca Foschi
- Dipartimento di Scienza e Alta Tecnologia Università degli Studi dell'Insubria Via Valleggio 9 IT-20100 Como Italy
| |
Collapse
|
25
|
Vera S, Vázquez A, Rodriguez R, Pozo SD, Urruzuno I, Cózar AD, Mielgo A, Palomo C. Synthesis of β-Hydroxy α-Amino Acids Through Brønsted Base-Catalyzed syn-Selective Direct Aldol Reaction of Schiff Bases of Glycine o-Nitroanilide. J Org Chem 2021; 86:7757-7772. [PMID: 33998227 PMCID: PMC9490875 DOI: 10.1021/acs.joc.1c00406] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/19/2023]
Abstract
![]()
Here
we report the highly enantio- and syn-selective
synthesis of β-hydroxy α-amino acids from glycine imine
derivatives under Brønsted base (BB) catalysis. The key of this
approach is the use of benzophenone-derived imine of glycine o-nitroanilide as a pronucleophile, where the o-nitroanilide framework provides an efficient hydrogen-bonding platform
that accounts for nucleophile reactivity and diastereoselectivity.
Collapse
Affiliation(s)
- Silvia Vera
- Departamento de Química Orgánica I, Universidad del País Vasco UPV/EHU, Manuel Lardizábal 3, 20018 San Sebastián, Spain
| | - Ana Vázquez
- Departamento de Química Orgánica I, Universidad del País Vasco UPV/EHU, Manuel Lardizábal 3, 20018 San Sebastián, Spain
| | - Ricardo Rodriguez
- Departamento de Química Orgánica I, Universidad del País Vasco UPV/EHU, Manuel Lardizábal 3, 20018 San Sebastián, Spain
| | - Sandra Del Pozo
- Departamento de Química Orgánica I, Universidad del País Vasco UPV/EHU, Manuel Lardizábal 3, 20018 San Sebastián, Spain
| | - Iñaki Urruzuno
- Departamento de Química Orgánica I, Universidad del País Vasco UPV/EHU, Manuel Lardizábal 3, 20018 San Sebastián, Spain
| | - Abel de Cózar
- Departamento de Química Orgánica I, Universidad del País Vasco UPV/EHU, Manuel Lardizábal 3, 20018 San Sebastián, Spain.,IKERBASQUE, Basque Foundation for Science, 48009 Bilbao, Spain
| | - Antonia Mielgo
- Departamento de Química Orgánica I, Universidad del País Vasco UPV/EHU, Manuel Lardizábal 3, 20018 San Sebastián, Spain
| | - Claudio Palomo
- Departamento de Química Orgánica I, Universidad del País Vasco UPV/EHU, Manuel Lardizábal 3, 20018 San Sebastián, Spain
| |
Collapse
|
26
|
Gugkaeva ZT, Smol'yakov AF, Maleev VI, Larionov VA. A general asymmetric synthesis of artificial aliphatic and perfluoroalkylated α-amino acids by Luche's cross-electrophile coupling reaction. Org Biomol Chem 2021; 19:5327-5332. [PMID: 34042928 DOI: 10.1039/d1ob00805f] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Aliphatic artificial α-amino acids (α-AAs) have attracted great interest in biochemistry and pharmacy. In this context, we developed a promising practical protocol for the asymmetric synthesis of these α-AAs through the selective and efficient intermolecular cross-electrophile coupling of Belokon's chiral dehydroalanine Ni(ii) complex with different alkyl and perfluoroalkyl iodides mediated by a dual Zn/Cu system. The reaction afforded diastereomeric complexes with dr up to 21.3 : 1 in 24-95% yields (19 examples). Exemplarily, three enantiomerically pure aliphatic α-AAs were obtained through acidic decomposition of (S,S)-diastereomers of Ni(ii) complexes. Importantly, the chiral auxiliary ligand (S)-BPB ((S)-2-(N-benzylprolyl)aminobenzophenone) was easily recycled by simple filtration after acidic complex decomposition and reused for the synthesis of the initial dehydroalanine Ni(ii) complex.
Collapse
Affiliation(s)
- Zalina T Gugkaeva
- A. N. Nesmeyanov Institute of Organoelement Compounds of Russian Academy of Sciences, Vavilov Str. 28, 119991 Moscow, Russian Federation.
| | - Alexander F Smol'yakov
- A. N. Nesmeyanov Institute of Organoelement Compounds of Russian Academy of Sciences, Vavilov Str. 28, 119991 Moscow, Russian Federation. and Plekhanov Russian University of Economics, Stremyanny per. 36, 117997 Moscow, Russian Federation
| | - Victor I Maleev
- A. N. Nesmeyanov Institute of Organoelement Compounds of Russian Academy of Sciences, Vavilov Str. 28, 119991 Moscow, Russian Federation.
| | - Vladimir A Larionov
- A. N. Nesmeyanov Institute of Organoelement Compounds of Russian Academy of Sciences, Vavilov Str. 28, 119991 Moscow, Russian Federation. and Peoples' Friendship University of Russia (RUDN University), Miklukho-Maklaya Str. 6, 117198 Moscow, Russian Federation
| |
Collapse
|
27
|
Rinehart NI, Zahrt AF, Henle JJ, Denmark SE. Dreams, False Starts, Dead Ends, and Redemption: A Chronicle of the Evolution of a Chemoinformatic Workflow for the Optimization of Enantioselective Catalysts. Acc Chem Res 2021; 54:2041-2054. [PMID: 33856771 DOI: 10.1021/acs.accounts.0c00826] [Citation(s) in RCA: 13] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
Abstract
Catalyst design in enantioselective catalysis has historically been driven by empiricism. In this endeavor, experimentalists attempt to qualitatively identify trends in structure that lead to a desired catalyst function. In this body of work, we lay the groundwork for an improved, alternative workflow that uses quantitative methods to inform decision making at every step of the process. At the outset, we define a library of synthetically accessible permutations of a catalyst scaffold with the philosophy that the library contains every potential catalyst we are willing to make. To represent these chiral molecules, we have developed general 3D representations, which can be calculated for tens of thousands of structures. This defines the total chemical space of a given catalyst scaffold; it is constructed on the basis of catalyst structure only without regard to a specific reaction or mechanism. As such, any algorithmic subset selection method, which is unsupervised (i.e., only considers catalyst structure), should provide an ideal initial screening set for any new reaction that can be catalyzed by that scaffold. Notably, because this design strategy, the same set of catalysts can be used for any reaction that can be catalyzed with that parent catalyst scaffold. These are tested experimentally, and statistical learning tools can be used to create a model relating catalyst structure to catalyst function. Further, this model can be used to predict the performance of each catalyst candidate in the greater database of virtual catalyst candidates. In this way, it is possible estimate the performance of tens of thousands of catalysts by experimentally testing a smaller subset. Using error assessment metrics, it is possible to understand the confidence in new predictions. An experimentalist using this tool can balance the predicted results (reward) with the prediction confidence (risk) when deciding which catalysts to synthesize next in an optimization campaign. These catalysts are synthesized and tested experimentally. At this stage, either the optimization is a success or the predicted values were incorrect and further optimization is required. In the case of the latter, the information can be fed back into the statistical learning model to refine the model, and this iterative process can be used to determine the optimal catalyst. In this body of work, we not only establish this workflow but quantitatively establish how best to execute each step. Herein, we evaluate several 3D molecular representations to determine how best to represent molecules. Several selection protocols are examined to best decide which set of molecules can be used to represent the library of interest. In addition, the number of reactions needed to make accurate, statistical learning models is evaluated. Taken together these components establish a tool ready to progress from the development stage to the utility stage. As such, current research endeavors focus on applying these tools to optimize new reactions.
Collapse
Affiliation(s)
- N. Ian Rinehart
- Roger Adams Laboratory, Department of Chemistry, University of Illinois, Urbana, Illinois 61801, United States
| | - Andrew F. Zahrt
- Roger Adams Laboratory, Department of Chemistry, University of Illinois, Urbana, Illinois 61801, United States
| | - Jeremy J. Henle
- Roger Adams Laboratory, Department of Chemistry, University of Illinois, Urbana, Illinois 61801, United States
| | - Scott E. Denmark
- Roger Adams Laboratory, Department of Chemistry, University of Illinois, Urbana, Illinois 61801, United States
| |
Collapse
|
28
|
Okuno K, Nakamura T, Shirakawa S. Asymmetric Catalysis of Chiral Bifunctional Selenides and Selenonium Salts Bearing a Urea Group. ASIAN J ORG CHEM 2021. [DOI: 10.1002/ajoc.202100001] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/28/2022]
Affiliation(s)
- Ken Okuno
- Department of Environmental Science Graduate School of Fisheries and Environmental Sciences Nagasaki University 1-14 Bunkyo-machi Nagasaki 852-8521 Japan
| | - Takumi Nakamura
- Department of Environmental Science Graduate School of Fisheries and Environmental Sciences Nagasaki University 1-14 Bunkyo-machi Nagasaki 852-8521 Japan
| | - Seiji Shirakawa
- Department of Environmental Science Graduate School of Fisheries and Environmental Sciences Nagasaki University 1-14 Bunkyo-machi Nagasaki 852-8521 Japan
| |
Collapse
|
29
|
García-Urricelqui A, de Cózar A, Mielgo A, Palomo C. Probing α-Amino Aldehydes as Weakly Acidic Pronucleophiles: Direct Access to Quaternary α-Amino Aldehydes by an Enantioselective Michael Addition Catalyzed by Brønsted Bases. Chemistry 2021; 27:2483-2492. [PMID: 33034390 DOI: 10.1002/chem.202004468] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/06/2020] [Indexed: 12/20/2022]
Abstract
The high tendency of α-amino aldehydes to undergo 1,2-additions and their relatively low stability under basic conditions have largely prevented their use as pronucleophiles in the realm of asymmetric catalysis, particularly for the production of quaternary α-amino aldehydes. Herein, it is demonstrated that the chemistry of α-amino aldehydes may be expanded beyond these limits by documenting the first direct α-alkylation of α-branched α-amino aldehydes with nitroolefins. The reaction produces densely functionalized products bearing up to two, quaternary and tertiary, vicinal stereocenters with high diastereo- and enantioselectivity. DFT modeling leads to the proposal that intramolecular hydrogen bonding between the NH group and the carbonyl oxygen atom in the starting α-amino aldehyde is key for reaction stereocontrol.
Collapse
Affiliation(s)
- Ane García-Urricelqui
- Departamento de Química Orgánica I, Universidad del País Vasco UPV/EHU, Manuel Lardizábal 3, 20018, San Sebastián, Spain
| | - Abel de Cózar
- Departamento de Química Orgánica I, Universidad del País Vasco UPV/EHU, Manuel Lardizábal 3, 20018, San Sebastián, Spain.,IKERBASQUE, Basque Foundation for Science, 48009, Bilbao, Spain
| | - Antonia Mielgo
- Departamento de Química Orgánica I, Universidad del País Vasco UPV/EHU, Manuel Lardizábal 3, 20018, San Sebastián, Spain
| | - Claudio Palomo
- Departamento de Química Orgánica I, Universidad del País Vasco UPV/EHU, Manuel Lardizábal 3, 20018, San Sebastián, Spain
| |
Collapse
|
30
|
Blackwell JH, Kumar R, Gaunt MJ. Visible-Light-Mediated Carbonyl Alkylative Amination to All-Alkyl α-Tertiary Amino Acid Derivatives. J Am Chem Soc 2021; 143:1598-1609. [PMID: 33428383 DOI: 10.1021/jacs.0c12162] [Citation(s) in RCA: 37] [Impact Index Per Article: 12.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Abstract
The all-alkyl α-tertiary amino acid scaffold represents an important structural feature in many biologically and pharmaceutically relevant molecules. Syntheses of this class of molecule, however, often involve multiple steps and require activating auxiliary groups on the nitrogen atom or tailored building blocks. Here, we report a straightforward, single-step, and modular methodology for the synthesis of all-alkyl α-tertiary amino esters. This new strategy uses visible light and a silane reductant to bring about a carbonyl alkylative amination reaction that combines a wide range of primary amines, α-ketoesters, and alkyl iodides to form functionally diverse all-alkyl α-tertiary amino esters. Brønsted acid-mediated in situ condensation of primary amine and α-ketoester delivers the corresponding ketiminium species, which undergoes rapid 1,2-addition of an alkyl radical (generated from an alkyl iodide by the action of visible light and silane reductant) to form an aminium radical cation. Upon a polarity-matched and irreversible hydrogen atom transfer from electron rich silane, the electrophilic aminium radical cation is converted to an all-alkyl α-tertiary amino ester product. The benign nature of this process allows for broad scope in all three components and generates structurally and functionally diverse suite of α-tertiary amino esters that will likely have widespread use in academic and industrial settings.
Collapse
Affiliation(s)
- J Henry Blackwell
- Department of Chemistry, University of Cambridge, Lensfield Road, Cambridge CB2 1EW, United Kingdom
| | - Roopender Kumar
- Department of Chemistry, University of Cambridge, Lensfield Road, Cambridge CB2 1EW, United Kingdom
| | - Matthew J Gaunt
- Department of Chemistry, University of Cambridge, Lensfield Road, Cambridge CB2 1EW, United Kingdom
| |
Collapse
|
31
|
New amino acid clubbed Schiff bases inhibit carbonic anhydrase II, α-glucosidase, and urease enzymes: in silico and in vitro. Med Chem Res 2021. [DOI: 10.1007/s00044-020-02696-0] [Citation(s) in RCA: 14] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
|
32
|
Lara-Cerón JA, Jiménez-Pérez VM, Molina-Paredes AA, Sánchez M, Dias HVR, Ramírez-Montes PI, Muñoz-Flores BM. Preferential intermolecular interactions in a racemic mixture of amino acid Schiff base, conformational structures in solid state, and DFT studies. NEW J CHEM 2021. [DOI: 10.1039/d0nj04720a] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
In this work, we report the green synthesis of a Shiff base [N-(2-hydroxy-1-naphthylidene)-l-phenylalanine (1)] derived from an α-amino acid through an ultrasound-assisted synthesis method with excellent chemical yield in a short period of time.
Collapse
Affiliation(s)
- Jesús A. Lara-Cerón
- Universidad Autónoma de Nuevo León
- Facultad de Ciencias Químicas
- Ciudad Universitaria
- Nuevo León
- Mexico
| | - Víctor M. Jiménez-Pérez
- Universidad Autónoma de Nuevo León
- Facultad de Ciencias Químicas
- Ciudad Universitaria
- Nuevo León
- Mexico
| | - Areli A. Molina-Paredes
- Universidad Autónoma de Nuevo León
- Facultad de Ciencias Químicas
- Ciudad Universitaria
- Nuevo León
- Mexico
| | - Mario Sánchez
- Centro de Investigación en Materiales Avanzados
- S.C., Alianza Norte 202
- PIIT
- Carretera Monterrey-Aeropuerto Km. 10
- Apodaca
| | - H. V. Rasika Dias
- Department of Chemistry and Biochemistry
- The University of Texas at Arlington
- Arlington
- USA
| | - Pedro I. Ramírez-Montes
- Universidad Nacional Autónoma de México
- Facultad de Estudios Superiores Cuautitlán
- Departamento de Matemáticas
- 54714 Cuautitlán Izcalli
- Mexico
| | - Blanca M. Muñoz-Flores
- Universidad Autónoma de Nuevo León
- Facultad de Ciencias Químicas
- Ciudad Universitaria
- Nuevo León
- Mexico
| |
Collapse
|
33
|
Fuller AA, Dounay AB, Schirch D, Rivera DG, Hansford KA, Elliott AG, Zuegg J, Cooper MA, Blaskovich MAT, Hitchens JR, Burris-Hiday S, Tenorio K, Mendez Y, Samaritoni JG, O’Donnell MJ, Scott WL. Multi-Institution Research and Education Collaboration Identifies New Antimicrobial Compounds. ACS Chem Biol 2020; 15:3187-3196. [PMID: 33242957 PMCID: PMC7928911 DOI: 10.1021/acschembio.0c00732] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/28/2022]
Abstract
![]()
New
antibiotics are urgently needed to address increasing rates
of multidrug resistant infections. Seventy-six diversely functionalized
compounds, comprising five structural scaffolds, were synthesized
and tested for their ability to inhibit microbial growth. Twenty-six
compounds showed activity in the primary phenotypic screen at the
Community for Open Antimicrobial Drug Discovery (CO-ADD). Follow-up
testing of active molecules confirmed that two unnatural dipeptides
inhibit the growth of Cryptococcus neoformans with
a minimum inhibitory concentration (MIC) ≤ 8 μg/mL. Syntheses
were carried out by undergraduate students at five schools implementing
Distributed Drug Discovery (D3) programs. This report showcases that
a collaborative research and educational process is a powerful approach
to discover new molecules inhibiting microbial growth. Educational
gains for students engaged in this project are highlighted in parallel
to the research advances. Aspects of D3 that contribute to its success,
including an emphasis on reproducibility of procedures, are discussed
to underscore the power of this approach to solve important research
problems and to inform other coupled chemical biology research and
teaching endeavors.
Collapse
Affiliation(s)
- Amelia A. Fuller
- Santa Clara University, Department of Chemistry & Biochemistry, Santa Clara, California 95053, United States
| | - Amy B. Dounay
- Department of Chemistry and Biochemistry, Colorado College, 14 E. Cache La Poudre Street, Colorado Springs, Colorado 80903, United States
| | - Douglas Schirch
- Department of Chemistry, Goshen College, 1700 South Main Street, Goshen, Indiana 46526, United States
| | - Daniel G. Rivera
- Center for Natural Products Research, Faculty of Chemistry, University of Havana, Zapata y G, 10400, La Habana, Cuba
| | - Karl A. Hansford
- Community for Open Antimicrobial Drug Discovery, Centre for Superbug Solutions, Institute for Molecular Bioscience, The University of Queensland, St. Lucia, Queensland 4072, Australia
| | - Alysha G. Elliott
- Community for Open Antimicrobial Drug Discovery, Centre for Superbug Solutions, Institute for Molecular Bioscience, The University of Queensland, St. Lucia, Queensland 4072, Australia
| | - Johannes Zuegg
- Community for Open Antimicrobial Drug Discovery, Centre for Superbug Solutions, Institute for Molecular Bioscience, The University of Queensland, St. Lucia, Queensland 4072, Australia
| | - Matthew A Cooper
- Community for Open Antimicrobial Drug Discovery, Centre for Superbug Solutions, Institute for Molecular Bioscience, The University of Queensland, St. Lucia, Queensland 4072, Australia
| | - Mark A. T. Blaskovich
- Community for Open Antimicrobial Drug Discovery, Centre for Superbug Solutions, Institute for Molecular Bioscience, The University of Queensland, St. Lucia, Queensland 4072, Australia
| | - Jacob R. Hitchens
- Department of Chemistry and Chemical Biology, Indiana University Purdue University Indianapolis, 402 N. Blackford Street, Indianapolis, Indiana 46202, United States
| | - Sarah Burris-Hiday
- Department of Chemistry and Chemical Biology, Indiana University Purdue University Indianapolis, 402 N. Blackford Street, Indianapolis, Indiana 46202, United States
| | - Kristiana Tenorio
- Santa Clara University, Department of Chemistry & Biochemistry, Santa Clara, California 95053, United States
| | - Yanira Mendez
- Center for Natural Products Research, Faculty of Chemistry, University of Havana, Zapata y G, 10400, La Habana, Cuba
| | - J. Geno Samaritoni
- Department of Chemistry and Chemical Biology, Indiana University Purdue University Indianapolis, 402 N. Blackford Street, Indianapolis, Indiana 46202, United States
| | - Martin J. O’Donnell
- Department of Chemistry and Chemical Biology, Indiana University Purdue University Indianapolis, 402 N. Blackford Street, Indianapolis, Indiana 46202, United States
| | - William L. Scott
- Department of Chemistry and Chemical Biology, Indiana University Purdue University Indianapolis, 402 N. Blackford Street, Indianapolis, Indiana 46202, United States
| |
Collapse
|
34
|
Abstract
After short historical introduction, interfacial mechanism of phase transfer catalyzed (PTC) reactions of organic anions, induced by aqueous NaOH or KOH in two-phase systems is formulated. Subsequently experimental evidence that supports the interfacial deprotonation as the key initial step of these reactions is presented.
Collapse
|
35
|
|
36
|
Ali AI, O'Donnell MJ, Scott WL, Samaritoni JG. A solid-phase synthetic route to N-acylated α-alkyl-d,l-homoserine lactones. Tetrahedron Lett 2020. [DOI: 10.1016/j.tetlet.2020.152328] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/23/2022]
|
37
|
Matsumoto Y, Sawamura J, Murata Y, Nishikata T, Yazaki R, Ohshima T. Amino Acid Schiff Base Bearing Benzophenone Imine As a Platform for Highly Congested Unnatural α-Amino Acid Synthesis. J Am Chem Soc 2020; 142:8498-8505. [PMID: 32316721 DOI: 10.1021/jacs.0c02707] [Citation(s) in RCA: 43] [Impact Index Per Article: 10.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
Unnatural α-amino acids are invaluable building blocks in synthetic organic chemistry and could upgrade the function of peptides. We developed a new mode for catalytic activation of amino acid Schiff bases, serving as a platform for highly congested unnatural α-amino acid synthesis. The redox active copper catalyst enabled efficient cross-coupling to construct contiguous tetrasubstituted carbon centers. The broad functional group compatibility highlights the mildness of the present catalysis. Notably, we achieved successive β-functionalization and oxidation of amino acid Schiff bases to afford dehydroalanine derivatives bearing tetrasubstituted carbon. A three-component cross-coupling reaction of an amino acid Schiff base, alkyl bromides, and styrene derivatives demonstrated the high utility of the present method. The diastereoselective reaction was also achieved using menthol derivatives as a chiral auxiliary, delivering enantiomerically enriched α-amino acid bearing α,β-continuous tetrasubstituted carbon. The synthesized highly congested unnatural α-amino acid could be derivatized and incorporated into peptide synthesis.
Collapse
Affiliation(s)
- Yohei Matsumoto
- Graduate School of Pharmaceutical Sciences, Kyushu University, Maidashi, Higashi-ku, Fukuoka 812-8582, Japan
| | - Jun Sawamura
- Graduate School of Pharmaceutical Sciences, Kyushu University, Maidashi, Higashi-ku, Fukuoka 812-8582, Japan
| | - Yumi Murata
- Graduate School of Science and Engineering, Yamaguchi University, Ube, Yamaguchi 755-8611, Japan
| | - Takashi Nishikata
- Graduate School of Science and Engineering, Yamaguchi University, Ube, Yamaguchi 755-8611, Japan
| | - Ryo Yazaki
- Graduate School of Pharmaceutical Sciences, Kyushu University, Maidashi, Higashi-ku, Fukuoka 812-8582, Japan
| | - Takashi Ohshima
- Graduate School of Pharmaceutical Sciences, Kyushu University, Maidashi, Higashi-ku, Fukuoka 812-8582, Japan
| |
Collapse
|
38
|
Nakamura T, Okuno K, Nishiyori R, Shirakawa S. Hydrogen‐Bonding Catalysis of Alkyl‐Onium Salts. Chem Asian J 2020; 15:463-472. [DOI: 10.1002/asia.201901652] [Citation(s) in RCA: 20] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/30/2019] [Indexed: 12/20/2022]
Affiliation(s)
- Takumi Nakamura
- Department of Environmental ScienceGraduate School of Fisheries and Environmental SciencesNagasaki University 1-14 Bunkyo-machi Nagasaki 852-8521 Japan
| | - Ken Okuno
- Department of Environmental ScienceGraduate School of Fisheries and Environmental SciencesNagasaki University 1-14 Bunkyo-machi Nagasaki 852-8521 Japan
| | - Ryuichi Nishiyori
- Department of Environmental ScienceGraduate School of Fisheries and Environmental SciencesNagasaki University 1-14 Bunkyo-machi Nagasaki 852-8521 Japan
| | - Seiji Shirakawa
- Department of Environmental ScienceGraduate School of Fisheries and Environmental SciencesNagasaki University 1-14 Bunkyo-machi Nagasaki 852-8521 Japan
| |
Collapse
|
39
|
Kondo Y, Kadota T, Hirazawa Y, Morisaki K, Morimoto H, Ohshima T. Scandium(III) Triflate Catalyzed Direct Synthesis of N-Unprotected Ketimines. Org Lett 2019; 22:120-125. [PMID: 31854997 DOI: 10.1021/acs.orglett.9b04038] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022]
Abstract
N-Unprotected ketimines are useful substrates and intermediates for synthesizing valuable nitrogen-containing compounds, but their potential applicability is limited by the available synthetic methods. To address this issue, we report a scandium(III) triflate catalyzed direct synthesis of N-unprotected ketimines. Using commercially available reagents and Lewis acid catalysts, ketones were directly transformed into the corresponding N-unprotected ketimines in high yields with broad functional group tolerance, even in multigram scales. The reactions were readily applicable for one-pot synthesis of important compounds such as a glycine Schiff base without isolation of N-unprotected ketimine intermediates. Preliminary mechanistic studies to clarify the reaction mechanism are also described.
Collapse
Affiliation(s)
- Yuta Kondo
- Graduate School of Pharmaceutical Sciences , Kyushu University , Maidashi 3-1-1 Higashi-ku , Fukuoka , Japan , 812-8582
| | - Tetsuya Kadota
- Graduate School of Pharmaceutical Sciences , Kyushu University , Maidashi 3-1-1 Higashi-ku , Fukuoka , Japan , 812-8582
| | - Yoshinobu Hirazawa
- Graduate School of Pharmaceutical Sciences , Kyushu University , Maidashi 3-1-1 Higashi-ku , Fukuoka , Japan , 812-8582
| | - Kazuhiro Morisaki
- Graduate School of Pharmaceutical Sciences , Kyushu University , Maidashi 3-1-1 Higashi-ku , Fukuoka , Japan , 812-8582
| | - Hiroyuki Morimoto
- Graduate School of Pharmaceutical Sciences , Kyushu University , Maidashi 3-1-1 Higashi-ku , Fukuoka , Japan , 812-8582
| | - Takashi Ohshima
- Graduate School of Pharmaceutical Sciences , Kyushu University , Maidashi 3-1-1 Higashi-ku , Fukuoka , Japan , 812-8582
| |
Collapse
|
40
|
da Silva Gomes R, Corey EJ. A Method for the Catalytic Enantioselective Synthesis of Chiral α-Azido and α-Amino Ketones from Racemic α-Bromo Ketones, and Its Generalization to the Formation of Bonds to C, O, and S. J Am Chem Soc 2019; 141:20058-20061. [PMID: 31821754 DOI: 10.1021/jacs.9b12315] [Citation(s) in RCA: 22] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/28/2022]
Abstract
A new and practical method has been developed for the transformation of racemic α-bromo ketones to chiral α-azido and α-amino ketones with high enantioselectivity using phase transfer, ion-pair mediated reactions with a recoverable chiral quaternary salt (10 mol %) as catalyst in fluorobenzene-water. The process has been generalized to a variety of other attachments including of C, O, S, and NHR.
Collapse
Affiliation(s)
- Roberto da Silva Gomes
- Department of Chemistry and Chemical Biology , Harvard University , Cambridge , Massachusetts 02138 , United States
| | - E J Corey
- Department of Chemistry and Chemical Biology , Harvard University , Cambridge , Massachusetts 02138 , United States
| |
Collapse
|
41
|
Kondo Y, Morisaki K, Hirazawa Y, Morimoto H, Ohshima T. A Convenient Preparation Method for Benzophenone Imine Catalyzed by Tetrabutylammonium Fluoride. Org Process Res Dev 2019. [DOI: 10.1021/acs.oprd.9b00226] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/28/2023]
Affiliation(s)
- Yuta Kondo
- Graduate School of Pharmaceutical Sciences, Kyushu University, Maidashi 3-1-1, Higashi-ku, Fukuoka 812-8582, Japan
| | - Kazuhiro Morisaki
- Graduate School of Pharmaceutical Sciences, Kyushu University, Maidashi 3-1-1, Higashi-ku, Fukuoka 812-8582, Japan
| | - Yoshinobu Hirazawa
- Graduate School of Pharmaceutical Sciences, Kyushu University, Maidashi 3-1-1, Higashi-ku, Fukuoka 812-8582, Japan
| | - Hiroyuki Morimoto
- Graduate School of Pharmaceutical Sciences, Kyushu University, Maidashi 3-1-1, Higashi-ku, Fukuoka 812-8582, Japan
| | - Takashi Ohshima
- Graduate School of Pharmaceutical Sciences, Kyushu University, Maidashi 3-1-1, Higashi-ku, Fukuoka 812-8582, Japan
| |
Collapse
|