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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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One-pot enantioselective synthesis of (S)-spirobrassinin and non-natural (S)-methylspirobrassinin from amino acids using a turnip enzyme. J Nat Med 2021; 75:308-318. [PMID: 33389552 DOI: 10.1007/s11418-020-01468-9] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/02/2020] [Accepted: 11/13/2020] [Indexed: 12/16/2022]
Abstract
The enantioselective synthesis of (S)-(-)-spirobrassinin, which features a unique sulfur-containing spirooxindole skeleton, was achieved by focusing on the phytoalexin generation in Brassicaceae plants. Specifically, (S)-(-)-spirobrassinin was obtained in a one-pot fashion from L-tryptophan through a reaction involving S-spirocyclization with various turnip enzymes and constituents, i.e., using the turnip as a reaction reagent, catalyst, and reaction vessel. Surprisingly, this strategy also enabled the one-pot enantioselective synthesis of the novel non-natural spirooxindole (S)-(-)-5-methylspirobrassinin from 5-methyl-DL-tryptophan.
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Liquid chromatographic chiral recognition of phytoalexins on immobilized polysaccharides chiral stationary phases. Unusual temperature behavior. J Chromatogr A 2019; 1601:178-188. [PMID: 31056269 DOI: 10.1016/j.chroma.2019.04.070] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/25/2019] [Revised: 04/26/2019] [Accepted: 04/27/2019] [Indexed: 12/24/2022]
Abstract
Three immobilized polysaccharide chiral stationary phases, Chiralpak IA, Chiralpak IB and Chiralpak IC, were used for the study of enantioseparation of 36 derivatives of natural indole phytoalexins, in most cases bioactive, including racemic spirobrassinin, 1-methoxyspirobrassinin and 1-methoxyspirobrassinol methyl ether. Almost all analytes were baseline resolved at least on two different polysaccharide columns in normal phase mode. The effects of mobile phase composition, the analyte structure and the column temperature on the retention and enantioseparation were investigated. Evaluation of the corresponding thermodynamic parameters using van´t Hoff plots (ln k versus 1/T) in the temperature range -15 to 50 °C indicated that separations were enthalpy controlled in most cases, but some entropy controlled separations were also observed. Moreover, unusual phenomenon, an increase retention with increasing temperature accompanied with increased resolution was observed on the Chiralpak IC column. The elution order of enantiomers was determined in some cases and reversed elution order was also observed.
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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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Kozlov O, Kalíková K, Gondová T, Budovská M, Salayová A, Tesařová E. Fast enantioseparation of indole phytoalexins in additive free supercritical fluid chromatography. J Chromatogr A 2019; 1596:209-216. [PMID: 30910386 DOI: 10.1016/j.chroma.2019.03.028] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/01/2018] [Revised: 03/13/2019] [Accepted: 03/16/2019] [Indexed: 11/26/2022]
Abstract
A series of chiral indole phytoalexins with potential anticancer and antimicrobial activity were enantioseparated in supercritical fluid chromatography. Two polysaccharide-based chiral stationary phases composed of tris-(3,5-dimethylphenylcarbamate) derivatives of amylose or cellulose coated on 2.5 μm silica particles were successfully used. The influences of the polysaccharide backbone, co-solvent type and co-solvent content in the mobile phase on retention, enantioselectivity and enantioresolution of indole phytoalexins were investigated. Fast baseline separations were achieved for 26 from 27 tested compounds. Amylose-based chiral stationary phase provided higher number of baseline resolutions of the indole phytoalexins than the cellulose-based one. However, certain complementary enantioresolution results towards the studied compounds were observed between the investigated columns. The relationship between structure of the indole phytoalexins and their chromatographic behavior in supercritical fluid chromatography was discussed.
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Affiliation(s)
- Oleksandr Kozlov
- Department of Analytical Chemistry, Faculty of Science, P. J. Šafárik University, Moyzesova 11, 040 01 Košice, Slovak Republic
| | - Květa Kalíková
- Department of Physical and Macromolecular Chemistry, Faculty of Science, Charles University, Hlavova 8, 12843, Prague, Czech Republic.
| | - Taťána Gondová
- Department of Analytical Chemistry, Faculty of Science, P. J. Šafárik University, Moyzesova 11, 040 01 Košice, Slovak Republic
| | - Mariana Budovská
- Department of Organic Chemistry, Faculty of Science, P. J. Šafárik University, Moyzesova 11, 040 01 Košice, Slovak Republic
| | - Aneta Salayová
- Department of Organic Chemistry, Faculty of Science, P. J. Šafárik University, Moyzesova 11, 040 01 Košice, Slovak Republic; Department of Chemistry, Biochemistry and Biophysics, Institute of Pharmaceutical Chemistry, University of Veterinary Medicine and Pharmacy, 041 81 Košice, Slovak Republic
| | - Eva Tesařová
- Department of Physical and Macromolecular Chemistry, Faculty of Science, Charles University, Hlavova 8, 12843, Prague, Czech Republic
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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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Han J, Kitagawa O, Wzorek A, Klika KD, Soloshonok VA. The self-disproportionation of enantiomers (SDE): a menace or an opportunity? Chem Sci 2018; 9:1718-1739. [PMID: 29675218 PMCID: PMC5892310 DOI: 10.1039/c7sc05138g] [Citation(s) in RCA: 80] [Impact Index Per Article: 13.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/03/2017] [Accepted: 01/12/2018] [Indexed: 01/05/2023] Open
Abstract
Herein we report on the well-documented, yet not widely known, phenomenon of the self-disproportionation of enantiomers (SDE): the spontaneous fractionation of scalemic material into enantioenriched and -depleted fractions when any physicochemical process is applied.
Herein we report on the well-documented, yet not widely known, phenomenon of the self-disproportionation of enantiomers (SDE): the spontaneous fractionation of scalemic material into enantioenriched and -depleted fractions when any physicochemical process is applied. The SDE has implications ranging from the origins of prebiotic homochirality to unconventional enantiopurification methods, though the risks of altering the enantiomeric excess (ee) unintentionally, regrettably, remain greatly unappreciated. While recrystallization is well known as an SDE process, occurrences of the SDE in other processes are much less recognized, e.g. sublimation and even distillation. But the most common process that many workers seem to be completely ignorant of is SDE via chromatography and reports have included all manner of structures, all types of interactions, and all forms of chromatography, including GC. The SDE can be either a blessing – as a means to obtain enantiopure samples from scalemates – or a curse, as unwitting alteration of the ee leads to errors in the reporting of results and/or misinterpretation of the system under study. Thus the ramifications of the SDE are relevant to any area involving chirality – natural products, asymmetric synthesis, etc. Moreover, there is grave concern regarding errors in the literature, in addition to the possible occurrence of valid results which may have been overlooked and thus remain unreported, as well as the potential for the SDE to alter the ee, particularly via chromatography, and the following concepts will be conveyed: (1) the SDE occurs under totally achiral conditions of (a) precipitation, (b) centrifugation, (c) evaporation, (d) distillation, (e) crystallization, (f) sublimation, and (g) achiral chromatography (e.g. column, flash, MPLC, HPLC, SEC, GC, etc.). (2) The SDE cannot be controlled simply by experimental accuracy and ignorance of the SDE unavoidably leads to mistakes in the recorded and reported stereochemical outcome of enantioselective transformations. (3) The magnitude of the SDE (the difference between the extremes of enantioenrichment and -depletion) can be controlled and used to: (a) minimize mistakes in the recorded experimental values and (b) to develop unconventional and preparatively superior methods for enantiopurification. (4) The magnitude of the SDE cannot be predicted but can be expected for compounds possessing SDE-phoric groups or which have a general tendency for strong hydrogen or halogen bonds or dipole–dipole or aromatic π–π interactions. (5) An SDE test and the rigorous reporting and description of applied physicochemical processes should become part of standard experimental practice to prevent the erroneous reporting of the stereochemical outcome of enantioselective catalytic reactions and the chirooptical properties of scalemates. New directions in the study of the SDE, including halogen bonding-based interactions and novel, unconventional enantiopurification methods such as pseudo-SDE (chiral selector-assisted SDE resolution of racemates), are also reported.
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Affiliation(s)
- Jianlin Han
- School of Chemistry and Chemical Engineering , State Key Laboratory of Coordination Chemistry , Jiangsu Key Laboratory of Advanced Organic Materials , Nanjing University , 210093 Nanjing , China .
| | - Osamu Kitagawa
- 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 .
| | - Karel D Klika
- Molecular Structure Analysis , German Cancer Research Center (DKFZ) , Im Neuenheimer Feld 280 , D-69009 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 , Alameda Urquijo 36-5, Plaza, Bizkaia , 48011 Bilbao , Spain
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Han J, Soloshonok VA, Klika KD, Drabowicz J, Wzorek A. Chiral sulfoxides: advances in asymmetric synthesis and problems with the accurate determination of the stereochemical outcome. Chem Soc Rev 2017; 47:1307-1350. [PMID: 29271432 DOI: 10.1039/c6cs00703a] [Citation(s) in RCA: 157] [Impact Index Per Article: 22.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/06/2023]
Abstract
Chiral sulfoxides are in extremely high demand in nearly every sector of the chemical industry concerned with the design and development of new synthetic reagents, drugs, and functional materials. The primary objective of this review is to update readers on the latest developments from the past five years (2011-2016) in the preparation of optically active sulfoxides. Methodologies covered include catalytic asymmetric sulfoxidation using either chemical, enzymatic, or hybrid biocatalytic means; kinetic resolution involving oxidation to sulfones, reduction to sulfides, modification of side chains, and imidation to sulfoximines; as well as various other methods including nucleophilic displacement at the sulfur atom for the desymmetrization of achiral sulfoxides, enantioselective recognition and separation based on either metal-organic frameworks (MOF's) or host-guest chemistry, and the Horner-Wadsworth-Emmons reaction. A second goal of this work concerns a critical discussion of the problem of the accurate determination of the stereochemical outcome of a reaction due to the self-disproportionation of enantiomers (SDE) phenomenon, particularly as it relates to chiral sulfoxides. The SDE is a little-appreciated phenomenon that can readily and spontaneously occur for scalemic samples when subjected to practically any physicochemical process. It has now been unequivocally demonstrated that ignorance in the SDE phenomenon inevitably leads to erroneous interpretation of the stereochemical outcome of catalytic enantioselective reactions, in particular, for the synthesis of chiral sulfoxides. It is hoped that this two-pronged approach to covering the chemistry of chiral sulfoxides will be appealing, engaging, and motivating for current research-active authors to respond to in their future publications in this exciting area of current research.
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Affiliation(s)
- Jianlin Han
- School of Chemistry and Chemical Engineering, State Key Laboratory of Coordination Chemistry, Jiangsu Key Laboratory of Advanced Organic Materials, Nanjing University, 210093 Nanjing, 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. and IKERBASQUE, Basque Foundation for Science, Alameda Urquijo 36-5, Plaza Bizkaia, 48011 Bilbao, Spain
| | - Karel D Klika
- Molecular Structure Analysis, German Cancer Research Center (DKFZ), Im Neuenheimer Feld 280, D-69009 Heidelberg, Germany.
| | - Józef Drabowicz
- Department of Heterooganic Chemistry, Center of Molecular and Macromolecular Studies, Polish Academy of Sciences, Sienkiewicza 112, 90-363 Łódź, Poland and Institute of Chemistry, Environmental Protection and Biotechnology, Jan Długosz University in Częstochowa, Armii Krajowej 13/15, 42-201 Częstochowa, Poland
| | - Alicja Wzorek
- Department of Organic Chemistry I, Faculty of Chemistry, University of the Basque Country UPV/EHU, Paseo Manuel Lardizábal 3, 20018 San Sebastián, Spain. and Institute of Chemistry, Jan Kochanowski University in Kielce, Swiętokrzyska 15G, 25-406 Kielce, Poland.
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Terada S, Hirai M, Honzawa A, Kitagawa O, Kamizela A, Wzorek A, Soloshonok VA. Possible Case of Halogen Bond-Driven Self-Disproportionation of Enantiomers (SDE) via Achiral Chromatography. Chemistry 2017; 23:14631-14638. [PMID: 28783208 DOI: 10.1002/chem.201703308] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/18/2017] [Indexed: 11/12/2022]
Abstract
The major breakthrough reported in this work is the discovery of likely halogen bond-driven self-disproportionation of enantiomers (SDE). Taking into account that the halogen-bonding interactions can be rationally designed and can match, or even exceed, the strength of the more familiar hydrogen bond, this discovery clearly opens an unexpected new direction of research in the areas of molecular chirality and the SDE phenomenon.
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Affiliation(s)
- Shumpei Terada
- Department of Applied Chemistry, Shibaura Institute of Technology, 3-7-5 Toyosu, Kohto-ku, Tokyo, 135-8548, Japan
| | - Motohiro Hirai
- Department of Applied Chemistry, Shibaura Institute of Technology, 3-7-5 Toyosu, Kohto-ku, Tokyo, 135-8548, Japan
| | - Ayaka Honzawa
- Department of Applied Chemistry, Shibaura Institute of Technology, 3-7-5 Toyosu, Kohto-ku, Tokyo, 135-8548, Japan
| | - Osamu Kitagawa
- Department of Applied Chemistry, Shibaura Institute of Technology, 3-7-5 Toyosu, Kohto-ku, Tokyo, 135-8548, Japan
| | - Angelika Kamizela
- 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.,Department of Organic Chemistry I, Faculty of Chemistry, University of the Basque Country UPV/EHU, Paseo Manuel Lardizábal 3, 20018, San Sebastián, Spain
| | - 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.,JKERBASQUE, Basque Foundation for Science, University of the Basque Country UPV/EHU, Maria Diaz de Haro 3, 48013, Bilbao, Spain
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10
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Lu X, Tang J, Dang X, Jing X, Xu K, Li H, Liang B. Chiral recognition and determination of enantiomeric excess of chiral compounds by UV-visible-shortwave near infrared diffuse reflectance spectroscopy with chemometrics. RSC Adv 2017. [DOI: 10.1039/c6ra24952c] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
Abstract
UV-vis-SWNIR DRS with chemometrics is applied to chiral recognition and determination of e.e values of tartaric acid for the first time.
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Affiliation(s)
- Xiaomei Lu
- College of Chemical Engineering
- Sichuan University
- Chengdu 610065
- P. R. China
| | - Jie Tang
- College of Chemical Engineering
- Sichuan University
- Chengdu 610065
- P. R. China
| | - Xinxin Dang
- College of Chemical Engineering
- Sichuan University
- Chengdu 610065
- P. R. China
| | - Xiaoli Jing
- College of Medical Technology
- Chengdu University of Traditional Chinese Medicine
- Chengdu 611137
- P. R. China
| | - Kailin Xu
- College of Chemical Engineering
- Sichuan University
- Chengdu 610065
- P. R. China
| | - Hui Li
- College of Chemical Engineering
- Sichuan University
- Chengdu 610065
- P. R. China
| | - Bing Liang
- College of Chemical Engineering
- Sichuan University
- Chengdu 610065
- P. R. China
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11
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Moskaľová M, Kozlov O, Gondová T, Budovská M, Armstrong DW. HPLC Enantioseparation of Novel Spirobrassinin Analogs on the Cyclofructan Chiral Stationary Phases. Chromatographia 2016. [DOI: 10.1007/s10337-016-3212-z] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
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12
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Moskaľová M, Petrovaj J, Gondová T, Budovská M, Armstrong DW. Enantiomeric separation of new phytoalexin analogs with cyclofructan chiral stationary phases in normal-phase mode. J Sep Sci 2016; 39:3669-3676. [PMID: 27484485 DOI: 10.1002/jssc.201600739] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/01/2016] [Revised: 07/25/2016] [Accepted: 07/25/2016] [Indexed: 11/07/2022]
Abstract
For the first time, three different derivatized cyclofructan chiral stationary phases were used for the direct high-performance liquid chromatographic enantiomeric separation of 11 new racemic analogs of a natural indole phytoalexin. This class of compounds is known to have significant antiproliferative activity and other potentially useful pharmacological properties. The effect of various experimental factors was investigated to optimize the separations in the normal-phase mode. It was found that the nature of polar modifier and additive in the mobile phase have significant impact on the enantioseparations. Better chiral recognition of analyzed compounds was achieved on (R)-naphthylethyl carbamate cyclofructan 6 than on isopropyl carbamate cyclofructan 6 and dimethylphenyl carbamate cyclofructan 7. The thermodynamic parameters showed that the chiral separation was enthalpy controlled in all cases.
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Affiliation(s)
- Marianna Moskaľová
- Department of Analytical Chemistry, Faculty of Science, P.J. Šafárik University, Košice, Slovak Republic
| | - Ján Petrovaj
- Department of Analytical Chemistry, Faculty of Science, P.J. Šafárik University, Košice, Slovak Republic
| | - Taťána Gondová
- Department of Analytical Chemistry, Faculty of Science, P.J. Šafárik University, Košice, Slovak Republic.
| | - Mariana Budovská
- Department of Organic Chemistry, Faculty of Science, P.J. Šafárik University, Košice, Slovak Republic
| | - Daniel W Armstrong
- Department of Chemistry and Biochemistry, University of Texas at Arlington, Arlington, TX, USA
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Wzorek A, Klika KD, Drabowicz J, Sato A, Aceña JL, Soloshonok VA. The self-disproportionation of the enantiomers (SDE) of methyl n-pentyl sulfoxide via achiral, gravity-driven column chromatography: a case study. Org Biomol Chem 2015; 12:4738-46. [PMID: 24873904 DOI: 10.1039/c4ob00831f] [Citation(s) in RCA: 29] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
This work explores the self-disproportionation of enantiomers (SDE) of chiral sulfoxides via achiral, gravity-driven column chromatography using methyl n-pentyl sulfoxide as a case study. A major finding of this work is the remarkable persistence and high magnitude of the SDE for the analyte. Thus, it is the first case where SDE is observed even in the presence of MeOH in the mobile phase. The study demonstrated the practical preparation, in line with theory, of enantiomerically pure (>99.9% ee) samples of methyl n-pentyl sulfoxide starting from a sample of only modest ee (<35%). Remarkably, it was found that the order of elution was inverted, i.e. enantiomerically depleted fractions preceded later eluting enantiomerically enriched ones, when the stationary phase was changed from silica gel to aluminum oxide. To the best of our knowledge, this is the first occurrence of inverted SDE behavior due solely to a change in the stationary phase. Aberrant SDE behavior was observed in that the ee did not always fall continuously during the progression of the chromatography, and this was attributed to the complexity of the system at hand which cannot be described in simple terms such as the formation only of homo- and heterochiral dimers based on a single interaction. The results nevertheless suggest that all compounds with a chiral sulfoxide moiety in their structure are likely to exhibit the SDE phenomenon and thus this work constitutes the first example of SDE predictability. Moreover, it could well be that optical purification based on the SDE phenomenon is a simple, convenient, and inexpensive method for the optical purification of this class of compounds with a high degree of proficiency.
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Affiliation(s)
- Alicja Wzorek
- Institute of Chemistry, Jan Kochanowski University in Kielce, Swiętokrzyska 15G, 25-406 Kielce, Poland
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Wzorek A, Sato A, Drabowicz J, Soloshonok VA, Klika KD. Enantiomeric Enrichmentsviathe Self-Disproportionation of Enantiomers (SDE) by Achiral, Gravity-Driven Column Chromatography: a Case Study UsingN-(1-Phenylethyl)acetamide for Optimizing the Enantiomerically Pure Yield and Magnitude of the SDE. Helv Chim Acta 2015. [DOI: 10.1002/hlca.201500041] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
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15
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Suzuki Y, Han J, Kitagawa O, Aceña JL, Klika KD, Soloshonok VA. A comprehensive examination of the self-disproportionation of enantiomers (SDE) of chiral amides via achiral, laboratory-routine, gravity-driven column chromatography. RSC Adv 2015. [DOI: 10.1039/c4ra13928c] [Citation(s) in RCA: 44] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
Abstract
The behavior of a series of chiral amides during column chromatography using an achiral stationary phase revealed that a self-disproportionation of enantiomers (SDE) was always observed regardless of amide structure or chromatographic conditions.
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Affiliation(s)
- Yuya Suzuki
- Department of Applied Chemistry
- Shibaura Institute of Technology
- Tokyo 135-8548
- Japan
| | - Jianlin Han
- School of Chemistry and Chemical Engineering
- Nanjing University
- 210093 Nanjing
- China
| | - Osamu Kitagawa
- Department of Applied Chemistry
- Shibaura Institute of Technology
- Tokyo 135-8548
- Japan
| | - José Luis Aceña
- Department of Organic Chemistry I
- Faculty of Chemistry
- University of the Basque Country UPV/EHU
- 20018 San Sebastián
- Spain
| | - Karel D. Klika
- Molecular Structure Analysis
- German Cancer Research Center (DKFZ)
- D-69009 Heidelberg
- Germany
| | - Vadim A. Soloshonok
- Department of Organic Chemistry I
- Faculty of Chemistry
- University of the Basque Country UPV/EHU
- 20018 San Sebastián
- Spain
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16
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Vanthuyne N, Roussel C. Chiroptical Detectors for the Study of Unusual Phenomena in Chiral Chromatography. Top Curr Chem (Cham) 2013; 340:107-51. [DOI: 10.1007/128_2013_441] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/21/2023]
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17
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Self-disproportionation of Enantiomers of Enantiomerically Enriched Compounds. Top Curr Chem (Cham) 2013; 341:301-39. [PMID: 23605252 DOI: 10.1007/128_2013_434] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/25/2023]
Abstract
This review describes self-disproportionation of enantiomers (SDE) of non-racemic mixtures, subjected to distillation, sublimation, or chromatography on achiral stationary phase using achiral eluent, which leads to the substantial enantiomeric enrichment and corresponding depletion in different fractions, as compared to the enantiomeric composition of the starting material. This phenomenon is of a very general nature as SDE has been reported for different classes of chiral organic compounds bearing various functional groups and possessing diverse elements of chirality. The literature data discussed in this review clearly suggests that SDE is typical for enantiomerically enriched chiral organic compounds and special care should always be taken in evaluation of the stereochemical outcome of enantioselective reactions as well as determination of enantiomeric ratios of non-racemic mixtures of natural products after any purification process. The role of molecular association of enantiomers on the magnitude and preparative efficiency of SDE, as a new, nonconventional method for enantiomerc purifications, is emphasized and discussed.
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18
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Gondová T, Petrovaj J, Kutschy P, Armstrong DW. Stereoselective separation of spiroindoline phytoalexins on R-naphthylethyl cyclofructan 6-based chiral stationary phase. J Chromatogr A 2013; 1272:100-5. [DOI: 10.1016/j.chroma.2012.11.083] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/12/2012] [Revised: 11/20/2012] [Accepted: 11/28/2012] [Indexed: 11/25/2022]
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19
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Advantages of electronic circular dichroism detection for the stereochemical analysis and characterization of drugs and natural products by liquid chromatography. J Chromatogr A 2012; 1269:69-81. [PMID: 23040981 DOI: 10.1016/j.chroma.2012.09.046] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/21/2012] [Revised: 09/10/2012] [Accepted: 09/17/2012] [Indexed: 11/21/2022]
Abstract
The need for analytical methods for the determination of the enantiomeric excess of chiral compounds increased significantly in the last decades, and enantioselective separation techniques resulted particularly efficient to this purpose. Moreover, when detection systems based on chiroptical properties (optical rotation or circular dichroism) are employed in high-performance liquid chromatography (HPLC), the stereochemistry of a chiral analyte can be fully determined. Indeed, the coupling of HPLC with chiroptical detection systems allows the simultaneous assessment of the absolute configuration of stereoisomers and the evaluation of the enantiomeric/diastereomeric excess of samples. These features are particularly important in the study of drugs and natural products provided with biological activity, because the assignment of their absolute stereochemistry is essential to establish reliable structure-activity relationships. The following review aims to discuss the analytical advantages arising from the employment of electronic circular dichroism (ECD) detection systems in stereochemical analysis by HPLC upon chiral and non-chiral stationary phases and their use for the stereochemical characterization of chiral drugs and natural compounds. The different methods for the correlation between absolute stereochemistry and chiroptical properties are critically discussed. Relevant HPLC applications of ECD detection systems are then reported, and their analytical advantages are highlighted. For instance, the importance of the concentration-independent anisotropy factor (g-factor; g=Δɛ/ɛ) for the determination of the stereoisomeric composition of samples upon non-chiral stationary phases is underlined, since its sensitivity makes ECD detection very well suited for the enantioselective analysis of large libraries of chiral compounds in relatively short times.
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Soloshonok VA, Roussel C, Kitagawa O, Sorochinsky AE. Self-disproportionation of enantiomers via achiral chromatography: a warning and an extra dimension in optical purifications. Chem Soc Rev 2012; 41:4180-8. [PMID: 22517405 DOI: 10.1039/c2cs35006h] [Citation(s) in RCA: 130] [Impact Index Per Article: 10.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
This tutorial review describes the self-disproportionation of enantiomers (SDE) of chiral, non-racemic compounds, subjected to chromatography on an achiral stationary phase using an achiral eluent, which leads to the substantial enantiomeric enrichment and the corresponding depletion in different fractions, as compared to the enantiomeric composition of the starting material. The physicochemical background of SDE is a dynamic formation of homo- or heterochiral dimeric or oligomeric aggregates of different chromatographic behavior. This phenomenon is of a very general nature as the SDE has been reported for different classes of organic compounds bearing various functional groups and possessing diverse elements of chirality (central, axial and helical chirality). The literature data discussed in this review clearly suggest that SDE via achiral chromatography might be expected for any given chiral enantiomerically enriched compound. This presents two very important issues for organic chemists. First, chromatographic purification of reaction products can lead to erroneous determination of the stereochemical outcome of catalytic asymmetric reactions and second, achiral chromatography can be used as a new, nonconventional method for optical purifications. The latter has tremendous practical potential as the currently available techniques are limited to crystallization or chiral chromatography. However, a further systematic study of SDE is needed to develop understanding of this phenomenon and to design practical chromatographic separation techniques for optical purification of non-racemic mixtures by achiral-phase chromatography.
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Affiliation(s)
- Vadim A Soloshonok
- Department of Organic Chemistry I, Faculty of Chemistry, University of the Basque Country UPV/EHU, 20018 San Sebastian, Spain.
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21
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Enantioseparation of Novel Amino Analogs of Indole Phytoalexins on Macrocyclic Glycopeptide-Based Chiral Stationary Phase. Chromatographia 2011. [DOI: 10.1007/s10337-011-2143-y] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/17/2022]
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22
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Chen WB, Wu ZJ, Hu J, Cun LF, Zhang XM, Yuan WC. Organocatalytic Direct Asymmetric Aldol Reactions of 3-Isothiocyanato Oxindoles to Ketones: Stereocontrolled Synthesis of Spirooxindoles Bearing Highly Congested Contiguous Tetrasubstituted Stereocenters. Org Lett 2011; 13:2472-5. [DOI: 10.1021/ol200724q] [Citation(s) in RCA: 175] [Impact Index Per Article: 13.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Affiliation(s)
- Wen-Bing Chen
- Chengdu Institute of Organic Chemistry, Chinese Academy of Sciences, Chengdu 610041, China
- Chengdu Institute of Biology, Chinese Academy of Sciences, Chengdu 610041, China
- Graduate School of Chinese Academy of Sciences, Beijing 100049, China
| | - Zhi-Jun Wu
- Chengdu Institute of Organic Chemistry, Chinese Academy of Sciences, Chengdu 610041, China
- Chengdu Institute of Biology, Chinese Academy of Sciences, Chengdu 610041, China
- Graduate School of Chinese Academy of Sciences, Beijing 100049, China
| | - Jing Hu
- Chengdu Institute of Organic Chemistry, Chinese Academy of Sciences, Chengdu 610041, China
- Chengdu Institute of Biology, Chinese Academy of Sciences, Chengdu 610041, China
- Graduate School of Chinese Academy of Sciences, Beijing 100049, China
| | - Lin-Feng Cun
- Chengdu Institute of Organic Chemistry, Chinese Academy of Sciences, Chengdu 610041, China
- Chengdu Institute of Biology, Chinese Academy of Sciences, Chengdu 610041, China
- Graduate School of Chinese Academy of Sciences, Beijing 100049, China
| | - Xiao-Mei Zhang
- Chengdu Institute of Organic Chemistry, Chinese Academy of Sciences, Chengdu 610041, China
- Chengdu Institute of Biology, Chinese Academy of Sciences, Chengdu 610041, China
- Graduate School of Chinese Academy of Sciences, Beijing 100049, China
| | - Wei-Cheng Yuan
- Chengdu Institute of Organic Chemistry, Chinese Academy of Sciences, Chengdu 610041, China
- Chengdu Institute of Biology, Chinese Academy of Sciences, Chengdu 610041, China
- Graduate School of Chinese Academy of Sciences, Beijing 100049, China
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Self-disproportionation of enantiomers of heterocyclic compounds having a tertiary trifluoromethyl alcohol center on chromatography with a non-chiral system. J Fluor Chem 2010. [DOI: 10.1016/j.jfluchem.2009.12.002] [Citation(s) in RCA: 37] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
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24
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Nieminen V, Murzin DY, Klika KD. NMR and molecular modeling of the dimeric self-association of the enantiomers of 1,1'-bi-2-naphthol and 1-phenyl-2,2,2-trifluoroethanol in the solution state and their relevance to enantiomer self-disproportionation on achiral-phase chromatography (ESDAC). Org Biomol Chem 2008; 7:537-42. [PMID: 19156320 DOI: 10.1039/b814905d] [Citation(s) in RCA: 41] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Molecular modeling of the homo- and heterochiral dimeric self-associates of the enantiomers of 1,1'-bi-2-naphthol and 1-phenyl-2,2,2-trifluoroethanol in solution has been performed in order to understand their NMR behavior and in light of the phenomenon of "enantiomer self-disproportionation on achiral-phase chromatography" (ESDAC). For 1,1'-bi-2-naphthol in C(6)D(6), distinct NMR signals for each enantiomer arise for some spins in non-racemic mixtures-the phenomenon of self-induced diastereomeric anisochronism (SIDA). The linear divergence of these split signals across an enantiomeric titration (a series of samples in which the percentage of one enantiomer is varied from 50-100% whilst maintaining a constant total concentration), as well as the near linear migration of certain signals in CDCl(3) across a similar enantiomeric titration, where signals were not observed to be split, is consistent with the calculated small energy differences between the homo- and heterochiral associates. For an enantiomeric titration of 1-phenyl-2,2,2-trifluoroethanol in n-hexane, NMR signals also remained unsplit but the noticeable migration of some revealed a skew indicative of a preference for the heterochiral associate. This was duly reflected in the calculations which provided a DeltaG value favoring the heterochiral associate by 2.4 kJ mol(-1). The relevance of these results to evaluating the likely occurrence of ESDAC is considered.
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Affiliation(s)
- Ville Nieminen
- Laboratory of Industrial Chemistry, Process Chemistry Centre, Abo Akademi University, FIN-20500 Abo, Finland
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25
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Taniguchi T, Monde K, Nakanishi K, Berova N. Chiral sulfinates studied by optical rotation, ECD and VCD: the absolute configuration of a cruciferous phytoalexin brassicanal C. Org Biomol Chem 2008; 6:4399-405. [DOI: 10.1039/b813437e] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/03/2023]
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26
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Soloshonok VA. Remarkable amplification of the self-disproportionation of enantiomers on achiral-phase chromatography columns. Angew Chem Int Ed Engl 2006; 45:766-9. [PMID: 16374792 DOI: 10.1002/anie.200503373] [Citation(s) in RCA: 184] [Impact Index Per Article: 10.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
Affiliation(s)
- Vadim A Soloshonok
- Department of Chemistry and Biochemistry, University of Oklahoma, 620 Parrington Oval, Room 208, Norman, OK 73019, USA.
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Self-disproportionation of enantiomers of (R)-ethyl 3-(3,5-dinitrobenzamido)-4,4,4-trifluorobutanoate on achiral silica gel stationary phase. J Fluor Chem 2006. [DOI: 10.1016/j.jfluchem.2005.11.004] [Citation(s) in RCA: 90] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
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28
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Soloshonok VA. Remarkable Amplification of the Self-Disproportionation of Enantiomers on Achiral-Phase Chromatography Columns. Angew Chem Int Ed Engl 2006. [DOI: 10.1002/ange.200503373] [Citation(s) in RCA: 31] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
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Monde K, Taniguchi T, Miura N, Kutschy P, Curillová Z, Pilátová M, Mojzis J. Chiral cruciferous phytoalexins: preparation, absolute configuration, and biological activity. Bioorg Med Chem 2005; 13:5206-12. [PMID: 15975798 DOI: 10.1016/j.bmc.2005.06.001] [Citation(s) in RCA: 38] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/04/2005] [Revised: 05/30/2005] [Accepted: 06/01/2005] [Indexed: 11/28/2022]
Abstract
Synthesized by an efficient one-pot spirocyclization method, two chiral cruciferous phytoalexins, 1-methoxyspirobrassinin (2) and 1-methoxyspirobrassinol methyl ether (4a), were prepared through optical resolution using the chiral HPLC method of corresponding racemates. The absolute configuration of natural (+)-2 was elucidated as R by using the direct comparison of ECD and VCD spectra with those of known (S)-(-)-spirobrassinin (1). Another chiral phytoalexin, (-)-4a, had its absolute configuration 2R,3R elucidated through the comparison of observed and calculated VCD. Interestingly, the absolute configurations of natural (S)-(-)-spirobrassinin (1) and (R)-(+)-1-methoxyspirobrassinin (2) were opposite of each other, even though their structures are almost similar, with the exception of an N-methoxy group. A significant difference in the antiproliferative activity between (2R,3R)-(-) and (2S,3S)-(+)-4a was observed.
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Affiliation(s)
- Kenji Monde
- Division of Biological Sciences, Graduate School of Science, Frontier Research Center for Post-Genomic Science and Technology, Hokkaido University, Kita-ku, Sapporo 001-0021, Japan.
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Ruszkowska J, Wróbel JT. Tryptophan-derived sulfur-containing phytoalexins--a general overview. ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 2004; 527:629-36. [PMID: 15206782 DOI: 10.1007/978-1-4615-0135-0_72] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/28/2023]
Abstract
Phytoalexins are low molecular weight antimicrobial compounds that are synthesized and accumulated in plants after their exposure to pathogenic microorganisms (bacteria, fungi, viruses and protozoans). They are extensively studied now as promising antifungal, potentially anticancer and plant diseases controlling agents. The article pertains to a group of indole-derived phytoalexins--brassinins, containing at least one sulfur atom in the side chain or in the ring(s), isolated from the cruciferous plants. Up today more than 20 compounds, closely related biogenetically, but exhibiting diversified biological activity have been identified. The survey summerises most promising recent results pertaining practical application of brassinins and camalexins.
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Affiliation(s)
- Joanna Ruszkowska
- Faculty of Chemistry, Warsaw University, L. Pasteur Str. 1, 02-093 Warsaw, Poland.
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Monde K, Taniguchi T, Miura N, Nishimura SI, Harada N, Dukor RK, Nafie LA. Preparation of cruciferous phytoalexin related metabolites, (−)-dioxibrassinin and (−)-3-cyanomethyl-3-hydroxyoxindole, and determination of their absolute configurations by vibrational circular dichroism (VCD). Tetrahedron Lett 2003. [DOI: 10.1016/s0040-4039(03)01513-2] [Citation(s) in RCA: 28] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
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32
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Szymura-Oleksiak J, Bojarski J, Aboul-Enein HY. Recent applications of stereoselective chromatography. Chirality 2002; 14:417-35. [PMID: 11984758 DOI: 10.1002/chir.10110] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
Some recent applications of stereoselective chromatography in the fields of clinical pharmacy, drug analysis, food, and natural products are reviewed. The review is documented with up-to-date literature, which will assist further expansion of research in these areas.
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Affiliation(s)
- Joanna Szymura-Oleksiak
- Department of Pharmacokinetics and Physical Pharmacy, Medical College, Jagiellonian University, Krakow, Poland
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Suchý M, Kutschy P, Monde K, Goto H, Harada N, Takasugi M, Dzurilla M, Balentová E. Synthesis, absolute configuration, and enantiomeric enrichment of a cruciferous oxindole phytoalexin, (S)-(-)-spirobrassinin, and its oxazoline analog. J Org Chem 2001; 66:3940-7. [PMID: 11375018 DOI: 10.1021/jo0155052] [Citation(s) in RCA: 143] [Impact Index Per Article: 6.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Stereochemical studies of a cruciferous oxindole phytoalexin, (S)-(-)-spirobrassinin [(-)-4], and its oxazoline analogue, spirooxazoline (11), were carried out. Racemic spirobrassinin [(+/-)-4] was synthesized by SOCl(2)- or MsCl-mediated cyclization of dioxibrassinin [(+/-)-8]. Treatment of (3-hydroxyoxindol-3-yl)methylammonium chloride [(+/-)-9] with CSCl(2) and subsequent methylation of the obtained spirooxazolidinethione (+/-)-10 afforded spirooxazoline [(+/-)-11]. Enantioresolution of (+/-)-4 and (+/-)-11 was achieved by derivatization with (S)-(-)-1-phenylethyl isocyanate (12), chromatographic separation of diastereomeric amides 13, 14 or 15, 16, and their cleavage with CH(3)ONa. Absolute configuration of the stereogenic center in natural (S)-(-)-4 was derived from the exciton, calculated via CD methods, and unequivocally confirmed by X-ray crystallographic analyses of 1-[1'S,4'R-(-)-camphanoyl] derivatives [(-)-19 and (-)-20] of (+)- and (-)-4. Novel enantiomeric enrichment phenomena of 4 and 11 were discovered during their chromatographic separations under achiral HPLC conditions. Screening of antifungal activity against the fungus Bipolaris leersiae revealed no significant dependence of this activity on absolute configuration.
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Affiliation(s)
- M Suchý
- Department of Organic Chemistry, P. J. Safárik University, Moyzesova 11, 041 67 Kosice, Slovak Republic
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Current awareness in phytochemical analysis. PHYTOCHEMICAL ANALYSIS : PCA 2001; 12:144-151. [PMID: 11708302 DOI: 10.1002/pca.554] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/23/2023]
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