1
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Mruc P, Olbrycht M, Korbetskyy M, Antos D. Altering the mobile phase composition to enhance self-disproportionation of enantiomers in achiral chromatography. J Chromatogr A 2024; 1715:464603. [PMID: 38168648 DOI: 10.1016/j.chroma.2023.464603] [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: 10/04/2023] [Revised: 12/13/2023] [Accepted: 12/22/2023] [Indexed: 01/05/2024]
Abstract
The influence of mobile phase composition on the efficiency of enantiomer separation by achiral chromatography (ACh) was investigated. The separation was induced by the phenomenon of self-disproportionation of enantiomers (SDE) triggered by their homo and hetero-chiral interactions in an achiral environment. Typically, SDE occurs in apolar mobile phases of weak elution strength, which causes the separation time to extend and the process productivity to deteriorate. To mitigate that effect, we altered the content of a strong solvent (modifier) in the mobile phase by use of a solvent gradient in which the target enantiomer was separated in the presence of the weak solvent, whereas the unresolved mixture of enantiomers was eluted by increasing the modifier content in the mobile phase. This enabled accelerating the solute elution while preserving the separation selectivity. The approach was examined for the separation of nonracemic mixtures of two structurally different compounds that exhibited the SDE effect in ACh, i.e., metalaxyl (MX) and methyl p-tolyl sulfoxide (MTSO). The target compound of the separation was the more abundant enantiomer in the enantiomeric mixture. The process realization was preceded by the determination of the effect of the modifier content on the separation yield for enantiomeric mixtures of MX and MTSO of different enantiomeric excess (ee). In the case of MX, yield of the pure target enantiomer varied from 2 %, for the maximum concentration of the modifier, to 45 % for the minimum modifier concentration and the largest ee used in the experiments. In the case of MTSO, the yield varied from minimum 40 % to maximum 66 %. To predict the process, we employed a dynamic model, in which underlying thermodynamic dependencies were implemented.
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Affiliation(s)
- Patrycja Mruc
- Doctoral School of the Rzeszów University of Technology/PL, Poland
| | - Maksymilian Olbrycht
- Department of Chemical and Process Engineering, Rzeszow University of Technology, Rzeszów, Poland
| | - Markiian Korbetskyy
- Department of Chemical and Process Engineering, Rzeszow University of Technology, Rzeszów, Poland
| | - Dorota Antos
- Department of Chemical and Process Engineering, Rzeszow University of Technology, Rzeszów, Poland.
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2
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Mazzotta S, Rositano V, Senaldi L, Bernardi A, Allegrini P, Appendino G. Scalemic natural products. Nat Prod Rep 2023; 40:1647-1671. [PMID: 37439042 DOI: 10.1039/d3np00014a] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 07/14/2023]
Abstract
Covering: up to the end of 2022The area of scalemic natural products is often enigmatic from a mechanistic standpoint, since low optical purity is observed in compounds having multiple contiguous stereogenic centers resulting from mechanistically distinct biogenetic steps. A scalemic state is rarely the result of a sloppy enzymatic activity, rather resulting from the expression of antipodal enzymes/directing proteins or from the erosion of optical purity by enzymatic or spontaneous reactions. Evidence for these processes is critically reviewed, identifying the mechanisms most often associated to the enzymatic generation of scalemic natural products and also discussing analytical exploitations of natural products' scalemicity.
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Affiliation(s)
- Sarah Mazzotta
- Dipartimento di Chimica, Università degli Studi di Milano, Via Golgi 19, 20133 Milano, Italy
| | - Vincenzo Rositano
- Dipartimento di Chimica, Università degli Studi di Milano, Via Golgi 19, 20133 Milano, Italy
- Indena SpA, Via Don Minzoni 6, 20049 Settala, MI, Italy
| | - Luca Senaldi
- Indena SpA, Via Don Minzoni 6, 20049 Settala, MI, Italy
| | - Anna Bernardi
- Dipartimento di Chimica, Università degli Studi di Milano, Via Golgi 19, 20133 Milano, Italy
| | | | - Giovanni Appendino
- Dipartimento di Scienze del Farmaco, Largo Donegani 2, 28100 Novara, Italy.
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3
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Hu S. Copper (II) Ions Induced Self-Disproportionation of Enantiomers in Capillary Electrophoresis for the Quantification of Atenolol Enantiomers. Molecules 2023; 28:5908. [PMID: 37570878 PMCID: PMC10420844 DOI: 10.3390/molecules28155908] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/20/2023] [Revised: 08/03/2023] [Accepted: 08/04/2023] [Indexed: 08/13/2023] Open
Abstract
Despite the fact that the self-disproportionation of enantiomers (SDE) has been found for several decades and has been widely used in crystallization, sublimation and chromatography for the purification or separation of nonracemic compounds, the phenomenon of SDE in capillary electrophoresis (CE) has never been reported up to now. Here, a new approach to separate enantiomers in CE based on SDE was demonstrated by introducing copper (II) ions into the separation media. The enantiomers of atenolol interact with copper ions to produce positively charged complexes with different electrophoretic mobilities from the single molecules. The dynamic equilibrium between homo- or heterochiral complexes (associates) and single molecules of atenolol enantiomers supports the manifestation of SDE. Different mobilities of the single molecules and associates, and different distribution of two enantiomers between the single molecules and associates caused by their different concentrations, produce a net difference in electrodriven migration velocities of the two enantiomers. The relative movement of two enantiomers causes a zone depleted in one enantiomer at the rear end of sample segment, giving a trapezoidal CE curve with a step at the end. Quantification of enantiomers is achieved according to the step height. The analysis does not rely on the use of enantiomerically pure chiral selector and the result agrees with that obtained by conventional chiral CE using a chiral selector.
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Affiliation(s)
- Shaoqiang Hu
- Henan Key Laboratory of Function-Oriented Porous Materials, College of Chemistry and Chemical Engineering, Luoyang Normal University, Luoyang 471934, China
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4
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Thadem N, Rajesh M, Balaboina H, Das S. Synthesis of bridgehead-azacycles via dual C-N/C-C annulation of α-amino acids, aminals and maleimides. Org Biomol Chem 2022; 20:6368-6383. [PMID: 35861324 DOI: 10.1039/d2ob01117d] [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
The synthesis of various bridged azacyclic adducts has recently become a reemerging topic due to their bioactive and natural product mimic profiles. Accordingly, herein, we report a method for easy access to succinamide-bridged azacyclic derivatives through the metal-free polarization-controlled dual C-N/C-C annulation of readily available α-amino acids, 2-amino benzaldehydes or pyrrole/indole-2-aldehyde and maleimide substrates. This cascade features a rare dipolarophile-induced diastereo-selective amidative annulation, followed by 3 + 2 cycloaddition as key steps.
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Affiliation(s)
- Nagender Thadem
- Department of Organic Synthesis & Process Chemistry, CSIR-Indian Institute of Chemical Technology (CSIR-IICT), Hyderabad 500007, India. .,Academy of Scientific and Innovative Research (AcSIR), Ghaziabad, 201002, India
| | - Manda Rajesh
- Department of Organic Synthesis & Process Chemistry, CSIR-Indian Institute of Chemical Technology (CSIR-IICT), Hyderabad 500007, India.
| | - Harikrishna Balaboina
- Department of Organic Synthesis & Process Chemistry, CSIR-Indian Institute of Chemical Technology (CSIR-IICT), Hyderabad 500007, India.
| | - Saibal Das
- Department of Organic Synthesis & Process Chemistry, CSIR-Indian Institute of Chemical Technology (CSIR-IICT), Hyderabad 500007, India. .,Academy of Scientific and Innovative Research (AcSIR), Ghaziabad, 201002, India
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5
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Han J, Dembinski R, Soloshonok VA, Klika KD. A Call for a Change in Policy Regarding the Necessity for SDE Tests to Validate the Veracity of the Outcome of Enantioselective Syntheses, the Inherent Chiral State of Natural Products, and Other Cases Involving Enantioenriched Samples. Molecules 2021; 26:molecules26133994. [PMID: 34208870 PMCID: PMC8272130 DOI: 10.3390/molecules26133994] [Citation(s) in RCA: 11] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/21/2021] [Accepted: 06/28/2021] [Indexed: 11/16/2022] Open
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, China;
| | - Roman Dembinski
- Department of Chemistry, Oakland University, 146 Library Drive, Rochester, MI 48309, USA;
- Department of Bioorganic Chemistry, Centre of Molecular and Macromolecular Studies, Polish Academy of Sciences, Sienkiewicza 112, 90-363 Łódź, Poland
| | - 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, Alameda Urquijo 36-5, Plaza Bizkaia, 48011 Bilbao, Spain
- Correspondence: (V.A.S.); (K.D.K.)
| | - Karel D. Klika
- Molecular Structure Analysis, German Cancer Research Center (DKFZ), Im Neuenheimer Feld 280, D-69120 Heidelberg, Germany
- Correspondence: (V.A.S.); (K.D.K.)
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Han J, Wzorek A, Klika KD, Soloshonok VA. Recommended Tests for the Self-Disproportionation of Enantiomers (SDE) to Ensure Accurate Reporting of the Stereochemical Outcome of Enantioselective Reactions. MOLECULES (BASEL, SWITZERLAND) 2021; 26:molecules26092757. [PMID: 34067099 PMCID: PMC8124418 DOI: 10.3390/molecules26092757] [Citation(s) in RCA: 16] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 04/25/2021] [Revised: 05/04/2021] [Accepted: 05/04/2021] [Indexed: 12/14/2022]
Abstract
The purpose of this review is to highlight the necessity of conducting tests to gauge the magnitude of the self-disproportionation of enantiomers (SDE) phenomenon to ensure the veracity of reported enantiomeric excess (ee) values for scalemic samples obtained from enantioselective reactions, natural products isolation, etc. The SDE always occurs to some degree whenever any scalemic sample is subjected to physicochemical processes concomitant with the fractionation of the sample, thus leading to erroneous reporting of the true ee of the sample if due care is not taken to either preclude the effects of the SDE by measurement of the ee prior to the application of physicochemical processes, suppressing the SDE, or evaluating all obtained fractions of the sample. Or even avoiding fractionation altogether if possible. There is a clear necessity to conduct tests to assess the magnitude of the SDE for the processes applied to samples and the updated and improved recommendations described herein cover chromatography and processes involving gas-phase transformations such as evaporation or sublimation.
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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, China;
| | - Alicja Wzorek
- Institute of Chemistry, Jan Kochanowski University in Kielce, Uniwersytecka 7, 25-406 Kielce, Poland;
| | - Karel D. Klika
- Molecular Structure Analysis, German Cancer Research Center (DKFZ), Im Neuenheimer Feld 280, D-69120 Heidelberg, Germany
- Correspondence: (K.D.K.); (V.A.S.)
| | - 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, Alameda Urquijo 36-5, Plaza Bizkaia, 48011 Bilbao, Spain
- Correspondence: (K.D.K.); (V.A.S.)
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7
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Flurbiprofen: A Study of the Behavior of the Scalemate by Chromatography, Sublimation, and NMR. Symmetry (Basel) 2021. [DOI: 10.3390/sym13040543] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022] Open
Abstract
2-(2-Fluoro-4-biphenyl) propionic acid (flurbiprofen), from the phenylalkanoic acid family of nonsteroidal anti-inflammatory drugs (NSAID’s), is currently on the pharmaceutical market as a racemate. This racemic compound was tested for its propensity to undergo the self-disproportionation of enantiomers (SDE) phenomenon by various forms of chromatography (SDEvC), such as routine gravity-driven column chromatography, medium-pressure liquid chromatography (MPLC), preparative thin-layer chromatography (PTLC), and size-exclusion chromatography (SEC), as well as by sublimation (SDEvS). Furthermore, examination by nuclear magnetic resonance (NMR) in various solvents found that flurbiprofen exhibited the phenomenon of self-induced diastereomeric anisochronism (SIDA). By measurement of the diffusion coefficient (D), the longitudinal relaxation time (T1), and the transverse relaxation time (T2) using NMR, as well as by electrospray ionization-mass spectrometry (ESI-MS) examinations, the preferred intermolecular association was found to be solvent dependent, e.g., heterochiral association was preferred in toluene, while homochiral association was preferred in more polar solvents. This study also attempted, unsuccessfully, to correlate the NMR measurements of flurbiprofen with chromatographic outcomes for the rationalization and prediction of chromatographic results based on NMR measurements. Because the intermolecular hydrogen bonding of the acid groups in flurbiprofen overwhelmingly predominates over other intermolecular interactions, flurbiprofen seemed to represent a good test case for this idea. The behavior of scalemic samples of flurbiprofen is important, as, although it is currently dispensed as a racemate, clinical applications of the R enantiomer have been investigated. SDEvC and SDEvS both have ramifications for the preparation, handling, and storage of enantioenriched flurbiprofen, and this concern applies to other chiral drugs as well.
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8
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Efimov IV, Kulikova LN, Zhilyaev DI, Voskressensky LG. Recent Advances in the Chemistry of Isocyanides with Activated Methylene Group. European J Org Chem 2020. [DOI: 10.1002/ejoc.202000890] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/27/2023]
Affiliation(s)
- Ilya V. Efimov
- Research Center: Molecular Design and Synthesis of Innovative Compounds for Medicine Peoples' Friendship University of Russia (RUDN University) Miklukho‐Maklaya st, 6 117198 Moscow Russia
| | - Larisa N. Kulikova
- Research Center: Molecular Design and Synthesis of Innovative Compounds for Medicine Peoples' Friendship University of Russia (RUDN University) Miklukho‐Maklaya st, 6 117198 Moscow Russia
| | - Dmitry I. Zhilyaev
- Research Center: Molecular Design and Synthesis of Innovative Compounds for Medicine Peoples' Friendship University of Russia (RUDN University) Miklukho‐Maklaya st, 6 117198 Moscow Russia
| | - Leonid G. Voskressensky
- Research Center: Molecular Design and Synthesis of Innovative Compounds for Medicine Peoples' Friendship University of Russia (RUDN University) Miklukho‐Maklaya st, 6 117198 Moscow Russia
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9
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Mei H, Han J, Klika KD, Izawa K, Sato T, Meanwell NA, Soloshonok VA. Applications of fluorine-containing amino acids for drug design. Eur J Med Chem 2019; 186:111826. [PMID: 31740056 DOI: 10.1016/j.ejmech.2019.111826] [Citation(s) in RCA: 124] [Impact Index Per Article: 24.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/01/2019] [Revised: 10/21/2019] [Accepted: 10/26/2019] [Indexed: 01/26/2023]
Abstract
Fluorine-containing amino acids are becoming increasingly prominent in new drugs due to two general trends in the modern pharmaceutical industry. Firstly, the growing acceptance of peptides and modified peptides as drugs; and secondly, fluorine editing has become a prevalent protocol in drug-candidate optimization. Accordingly, fluorine-containing amino acids represent one of the more promising and rapidly developing areas of research in organic, bio-organic and medicinal chemistry. The goal of this Review article is to highlight the current state-of-the-art in this area by profiling 42 selected compounds that combine fluorine and amino acid structural elements. The compounds under discussion represent pharmaceutical drugs currently on the market, or in clinical trials as well as examples of drug-candidates that although withdrawn from development had a significant impact on the progress of medicinal chemistry and/or provided a deeper understanding of the nature and mechanism of biological action. For each compound, we present features of biological activity, a brief history of the design principles and the development of the synthetic approach, focusing on the source of tailor-made amino acid structures and fluorination methods. General aspects of the medicinal chemistry of fluorine-containing amino acids and synthetic methodology are briefly discussed.
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Affiliation(s)
- Haibo Mei
- College of Chemical Engineering, Nanjing Forestry University, Nanjing, 210037, China
| | - Jianlin Han
- College of Chemical Engineering, Nanjing Forestry University, Nanjing, 210037, China
| | - Karel D Klika
- Molecular Structure Analysis, German Cancer Research Center (DKFZ), Im Neuenheimer Feld 280, D-69120 Heidelberg, Germany
| | - Kunisuke Izawa
- Hamari Chemicals Ltd., 1-4-29 Kunijima, Higashi-Yodogawa-ku, Osaka, 533-0024, Japan.
| | - Tatsunori Sato
- Hamari Chemicals Ltd., 1-4-29 Kunijima, Higashi-Yodogawa-ku, Osaka, 533-0024, Japan
| | - Nicholas A Meanwell
- Department of Discovery Chemistry, Bristol-Myers Squibb Research and Development, PO Box 4000, Princeton, NJ, 08543-4000, United States.
| | - Vadim A Soloshonok
- Department of Organic Chemistry I, 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.
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10
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Kwiatkowska M, Marcinkowska M, Wzorek A, Pajkert R, Han J, Klika KD, Soloshonok VA, Röschenthaler GV. The self-disproportionation of enantiomers (SDE) via column chromatography of β-amino-α,α-difluorophosphonic acid derivatives. Amino Acids 2019; 51:1377-1385. [PMID: 31468209 DOI: 10.1007/s00726-019-02774-7] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/18/2019] [Accepted: 08/18/2019] [Indexed: 01/05/2023]
Abstract
This work presents the first study of the self-disproportionation of enantiomers via chromatography (SDEvC) of β-aminophosphonic acid esters, several of which have been synthesized for the first time. Three types of structures were examined, N-acetylated, dipeptide construction with N-Cbz glycine, and a free amine. In the latter case, this is the first time that SDEvC has been reported for free amine amino acids. In all the three types of structures, significant SDE magnitudes (Δee's up to 55%) were exhibited underscoring the ubiquitous nature of the SDE phenomenon. Chemical models of homo- versus heterochiral intermolecular interactions are proposed to rationalize the SDE magnitude differences amongst these new β-aminophosphonic acid derivatives. In addition, the incorporation of additional, competing binding modes to a molecule, was found to lead to a reduction of the SDE magnitude by shifting the intermolecular binding away from the stereogenic center and/or by leading to a convoluted binding system that disrupts the structured and relatively stable assemblies that give rise to the SDE.
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Affiliation(s)
- Magdalena Kwiatkowska
- Institute of Chemistry, Jan Kochanowski University in Kielce, Świętokrzyska 15G, 25-406, Kielce, Poland
| | - Magdalena Marcinkowska
- Institute of Chemistry, Jan Kochanowski University in Kielce, Świętokrzyska 15G, 25-406, Kielce, Poland
| | - Alicja Wzorek
- Institute of Chemistry, Jan Kochanowski University in Kielce, Świętokrzyska 15G, 25-406, Kielce, Poland.
| | - Romana Pajkert
- Department of Life Sciences and Chemistry, Jacobs University Bremen gGmbH, 28759, Bremen, Germany
| | - Jianlin Han
- Jiangsu Co-Innovation Center of Efficient Processing and Utilization of Forest Resources, College of Chemical Engineering, Nanjing Forestry University, Nanjing, 210037, Jiangsu, China.
| | - Karel D Klika
- Molecular Structure Analysis, German Cancer Research Center (DKFZ), Im Neuenheimer Feld 280, 69120, Heidelberg, Germany
| | - 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.
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11
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The self-disproportionation of enantiomers (SDE) of amino acids and their derivatives. Amino Acids 2019; 51:865-889. [PMID: 30903285 DOI: 10.1007/s00726-019-02729-y] [Citation(s) in RCA: 23] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/11/2019] [Accepted: 03/18/2019] [Indexed: 10/27/2022]
Abstract
This review covers the phenomenon of the self-disproportionation of enantiomers (SDE) of amino acids and their derivatives in all its guises from phase transformations (recrystallization, sublimation, and distillation), to the application of force fields, through to chromatography including HPLC, MPLC, gravity-driven column chromatography, and SEC. The relevance of the SDE phenomenon to amino acid research and to marketed pharmaceuticals is clear given the potential for alteration of the enantiomeric excess of a portion of a scalemic sample. In addition, the possible contribution of the SDE phenomenon to the genesis of prebiotic homochirality is considered.
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12
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Hosaka T, Imai T, Wzorek A, Marcinkowska M, Kolbus A, Kitagawa O, Soloshonok VA, Klika KD. The self-disproportionation of enantiomers (SDE) of α-amino acid derivatives: facets of steric and electronic properties. Amino Acids 2018; 51:283-294. [PMID: 30311082 DOI: 10.1007/s00726-018-2664-x] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/09/2018] [Accepted: 10/08/2018] [Indexed: 12/19/2022]
Abstract
α-Amino acids (α-AAs) are in extremely high demand in nearly every sector of the food and health-related chemical industries and continue to be the subject of intense multidisciplinary research. The self-disproportionation of enantiomers (SDE) is an emerging and one of the least studied areas of α-AA or enantiomeric properties, critically important for their production and application. In the present work, we report a detailed study of the SDE via achiral, gravity-driven column chromatography for a set of N-acylated, N-carbonylated, N-fluoroacylated, and N-thioacylated α-amino acid esters. As well as thioacylation, attention was paid to the effect of altering the R group of the ester functionality, the side chain, or that of the acyl group attached to the amide nitrogen, whereby it was found that electron-withdrawing groups in the latter moiety had a pronounced effect on the magnitude and behavior of the resulting SDE phenomenon. Intriguingly, in the case of N-fluoroacylated derivatives, by favoring the formation of dimeric associates and effecting a strong bias toward homochiral associates over heterochiral associates, the SDE magnitude was greatly reduced contrary to intuitive expectations. Energy estimates resulted from DFT calculations.
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Affiliation(s)
- Takuma Hosaka
- Department of Applied Chemistry, Shibaura Institute of Technology, 3-7-5 Toyosu, Kohto-ku, Tokyo, 135-8548, Japan
| | - Tomomi Imai
- Department of Applied Chemistry, Shibaura Institute of Technology, 3-7-5 Toyosu, Kohto-ku, Tokyo, 135-8548, Japan
| | - Alicja Wzorek
- Institute of Chemistry, Jan Kochanowski University in Kielce, Świętokrzyska 15G, 25-406, Kielce, Poland. .,Department of Organic Chemistry I, Faculty of Chemistry, University of the Basque Country UPV/EHU, Paseo Manuel Lardizábal 3, 20018, San Sebastián, Spain.
| | - Magdalena Marcinkowska
- Institute of Chemistry, Jan Kochanowski University in Kielce, Świętokrzyska 15G, 25-406, Kielce, Poland
| | - Anna Kolbus
- Institute of Chemistry, Jan Kochanowski University in Kielce, Świętokrzyska 15G, 25-406, Kielce, Poland
| | - Osamu Kitagawa
- Department of Applied Chemistry, Shibaura Institute of Technology, 3-7-5 Toyosu, Kohto-ku, Tokyo, 135-8548, Japan
| | - 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.
| | - Karel D Klika
- Molecular Structure Analysis, German Cancer Research Center (DKFZ), Im Neuenheimer Feld 280, 69120, Heidelberg, Germany.
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13
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Zhu Y, Mao Y, Mei H, Pan Y, Han J, Soloshonok VA, Hayashi T. Palladium-Catalyzed Asymmetric Allylic Alkylations of Colby Pro-Enolates with MBH Carbonates: Enantioselective Access to Quaternary C-F Oxindoles. Chemistry 2018; 24:8994-8998. [PMID: 29683211 DOI: 10.1002/chem.201801670] [Citation(s) in RCA: 36] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/04/2018] [Indexed: 12/21/2022]
Abstract
Owing to the innovative applications of fluorinated compounds in many areas of technology and medicine, methods for the preparation of C-F quaternary fluorine containing compounds are in extremely high demand. Here, we report the discovery of a general procedure for an SN 2 reaction catalyzed by Pd/Ding-SKP-type ligands, and that occurs between Colby pro-enolates with MBH carbonates to afford the corresponding products featuring two consecutive stereogenic carbons, including a C-F quaternary stereogenic center. The reactions readily occur at ambient temperatures with high chemical yields and in excellent chemo-, diastereo- and enantioselective manners. This practically attractive stereochemical outcome, coupled with the operational simplicity and structural generality, bodes well for the synthetic application of this process in the preparation of a novel class of biologically relevant fluorine-containing compounds.
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Affiliation(s)
- Yi Zhu
- School of Chemistry and Chemical Engineering, State Key Laboratory of Coordination Chemistry, Jiangsu Key Laboratory of Advanced Organic Materials, Nanjing University, Nanjing, 210093, China
| | - Yu Mao
- School of Chemistry and Chemical Engineering, State Key Laboratory of Coordination Chemistry, Jiangsu Key Laboratory of Advanced Organic Materials, Nanjing University, Nanjing, 210093, China
| | - Haibo Mei
- School of Chemistry and Chemical Engineering, State Key Laboratory of Coordination Chemistry, Jiangsu Key Laboratory of Advanced Organic Materials, Nanjing University, Nanjing, 210093, China
| | - Yi Pan
- School of Chemistry and Chemical Engineering, State Key Laboratory of Coordination Chemistry, Jiangsu Key Laboratory of Advanced Organic Materials, Nanjing University, Nanjing, 210093, China
| | - Jianlin Han
- School of Chemistry and Chemical Engineering, State Key Laboratory of Coordination Chemistry, Jiangsu Key Laboratory of Advanced Organic Materials, Nanjing University, Nanjing, 210093, China
| | - 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, Maria Diaz de Haro 3, 48013, Bilbao, Spain
| | - Tamio Hayashi
- Division of Chemistry and Biological Chemistry, School of Physical and Mathematical Sciences, Nanyang Technological University, 21 Nanyang Link, Singapore, 637371, Singapore
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