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Vezse P, Benda B, Fekete A, Golcs Á, Tóth T, Huszthy P. Covalently Immobilizable Tris(Pyridino)-Crown Ether for Separation of Amines Based on Their Degree of Substitution. MOLECULES (BASEL, SWITZERLAND) 2022; 27:molecules27092838. [PMID: 35566195 PMCID: PMC9103866 DOI: 10.3390/molecules27092838] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 04/01/2022] [Revised: 04/19/2022] [Accepted: 04/27/2022] [Indexed: 11/17/2022]
Abstract
A great number of biologically active compounds contain at least one amine function. Appropriate selectivity can only be accomplished in a few cases upon the substitution of these groups, thus functionalization of amines generally results in a mixture of them. The separation of these derivatives with very similar characteristics can only be performed on a preparative scale or by applying pre-optimized HPLC methods. A tris(pyridino)-crown ether was designed and synthetized for overcoming these limitations at a molecular level. It is demonstrated, that this selector molecule is able to distinguish protonated primary, secondary and tertiary amines by the formation of reversible complexes with different stabilities. This degree of substitution-specific molecular recognition of amines opens the door to develop separation processes primarily focusing on the purification of biologically active compounds in a nanomolar scale.
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Affiliation(s)
- Panna Vezse
- Department of Organic Chemistry and Technology, Budapest University of Technology and Economics, 1111 Budapest, Hungary; (P.V.); (B.B.); (A.F.); (T.T.); (P.H.)
| | - Bianka Benda
- Department of Organic Chemistry and Technology, Budapest University of Technology and Economics, 1111 Budapest, Hungary; (P.V.); (B.B.); (A.F.); (T.T.); (P.H.)
| | - András Fekete
- Department of Organic Chemistry and Technology, Budapest University of Technology and Economics, 1111 Budapest, Hungary; (P.V.); (B.B.); (A.F.); (T.T.); (P.H.)
| | - Ádám Golcs
- Department of Organic Chemistry and Technology, Budapest University of Technology and Economics, 1111 Budapest, Hungary; (P.V.); (B.B.); (A.F.); (T.T.); (P.H.)
- Correspondence:
| | - Tünde Tóth
- Department of Organic Chemistry and Technology, Budapest University of Technology and Economics, 1111 Budapest, Hungary; (P.V.); (B.B.); (A.F.); (T.T.); (P.H.)
- Institute for Energy Security and Environmental Safety, Centre for Energy Research, 1121 Budapest, Hungary
| | - Péter Huszthy
- Department of Organic Chemistry and Technology, Budapest University of Technology and Economics, 1111 Budapest, Hungary; (P.V.); (B.B.); (A.F.); (T.T.); (P.H.)
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2
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Pál D, Móczár I, Szemenyei B, Marczona D, Kocsis I, Prikler G, Vezse P, Baranyai P, Huszthy P. Pyridino-18-crown-6 ether type chemosensors containing a benzothiazole fluorophore unit: Synthesis and enantiomeric recognition studies. Tetrahedron 2019. [DOI: 10.1016/j.tet.2019.04.024] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022]
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3
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Structural characterization of the crystalline diastereomeric complexes of enantiopure dimethylacridino-18-crown-6 ether and the enantiomers of 1-(1-naphthyl)ethylamine hydrogen perchlorate. Struct Chem 2016. [DOI: 10.1007/s11224-016-0818-6] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/21/2022]
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4
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Szemenyei B, Móczár I, Pál D, Kocsis I, Baranyai P, Huszthy P. Synthesis and Enantiomeric Recognition Studies of Optically Active Pyridino-Crown Ethers Containing an Anthracene Fluorophore Unit. Chirality 2016; 28:562-8. [DOI: 10.1002/chir.22614] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/16/2016] [Revised: 05/12/2016] [Accepted: 05/25/2016] [Indexed: 01/13/2023]
Affiliation(s)
- Balázs Szemenyei
- Department of Organic Chemistry and Technology; Budapest University of Technology and Economics; Budapest Hungary
| | - Ildikó Móczár
- Department of Organic Chemistry and Technology; Budapest University of Technology and Economics; Budapest Hungary
| | - Dávid Pál
- Department of Organic Chemistry and Technology; Budapest University of Technology and Economics; Budapest Hungary
| | - Ivett Kocsis
- Department of Organic Chemistry and Technology; Budapest University of Technology and Economics; Budapest Hungary
| | - Péter Baranyai
- “Lendület” Supramolecular Chemistry Research Group, Institute of Organic Chemistry, Research Centre of Natural Sciences; Hungarian Academy of Sciences; Budapest Hungary
| | - Péter Huszthy
- Department of Organic Chemistry and Technology; Budapest University of Technology and Economics; Budapest Hungary
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5
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Lévai S, Németh T, Fődi T, Kupai J, Tóth T, Huszthy P, Balogh GT. Studies of a pyridino-crown ether-based chiral stationary phase on the enantioseparation of biogenic chiral aralkylamines and α-amino acid esters by high-performance liquid chromatography. J Pharm Biomed Anal 2015. [PMID: 26218505 DOI: 10.1016/j.jpba.2015.07.011] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
This paper reports the enantioseparation ability of a pyridino-18-crown-6 ether-based chiral stationary phase [(S,S)-CSP-1]. The enantiomeric discrimination of chiral stationary phase (S,S)-CSP-1 was evaluated by HPLC using the mixtures of enantiomers of various protonated primary aralkylamines [1-phenylethylamine hydrogen perchlorate (PEA), 2,3-dihydro-1H-inden-1-amine (1-aminoindan), 2,2'-(1,2-diaminoethane-1,2-diyl) diphenol (HPEN)] and perchlorate salts of α-amino acid esters [alanine benzyl ester (Ala-OBn), phenylalanine benzyl ester (Phe-OBn), phenylalanine methyl ester (Phe-OMe), phenylglycine methyl ester (PhGly-OMe), glutamic acid dibenzyl ester (Glu-diOBn), and valine benzyl ester (Val-OBn)]. The best enantioseparation was achieved in the case of PEA. The high enantioselectivity was rationalized by the strong π-π interaction of the extended π system of the aryl-substituted pyridine unit.
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Affiliation(s)
- Sándor Lévai
- Compound Profiling Laboratory, Chemical Works of Gedeon Richter Plc., H-1475 Budapest, PO Box 27, Hungary
| | - Tamás Németh
- Department of Organic Chemistry and Technology, Budapest University of Technology and Economics, H-1521 Budapest, PO Box 91, Hungary
| | - Tamás Fődi
- Compound Profiling Laboratory, Chemical Works of Gedeon Richter Plc., H-1475 Budapest, PO Box 27, Hungary
| | - József Kupai
- Department of Organic Chemistry and Technology, Budapest University of Technology and Economics, H-1521 Budapest, PO Box 91, Hungary
| | - Tünde Tóth
- Department of Organic Chemistry and Technology, Budapest University of Technology and Economics, H-1521 Budapest, PO Box 91, Hungary
| | - Péter Huszthy
- Department of Organic Chemistry and Technology, Budapest University of Technology and Economics, H-1521 Budapest, PO Box 91, Hungary
| | - György Tibor Balogh
- Compound Profiling Laboratory, Chemical Works of Gedeon Richter Plc., H-1475 Budapest, PO Box 27, Hungary.
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6
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Nemeth T, Levai S, F di T, Kupai J, Turos G, Toth T, Huszthy P, Balogh GT. A Novel Method for the Preparation of a Chiral Stationary Phase Containing an Enantiopure Acridino-18-Crown-6 Ether Selector. J Chromatogr Sci 2014; 53:431-5. [DOI: 10.1093/chromsci/bmu157] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022]
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7
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Németh T, Lévai S, Kormos A, Kupai J, Tóth T, Balogh GT, Huszthy P. Preparation and Studies of Chiral Stationary Phases Containing Enantiopure Acridino-18-Crown-6 Ether Selectors. Chirality 2014; 26:651-4. [DOI: 10.1002/chir.22361] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/15/2014] [Accepted: 07/03/2014] [Indexed: 11/09/2022]
Affiliation(s)
- Tamás Németh
- Budapest University of Technology and Economics; Budapest Hungary
| | - Sándor Lévai
- Compound Profiling Laboratory; Chemical Works of Gedeon Richter Plc.; Budapest Hungary
| | - Attila Kormos
- Budapest University of Technology and Economics; Budapest Hungary
| | - József Kupai
- Budapest University of Technology and Economics; Budapest Hungary
| | - Tünde Tóth
- Budapest University of Technology and Economics; Budapest Hungary
| | - György Tibor Balogh
- Compound Profiling Laboratory; Chemical Works of Gedeon Richter Plc.; Budapest Hungary
| | - Péter Huszthy
- Budapest University of Technology and Economics; Budapest Hungary
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8
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Preparation of pyridino-crown ether-based new chiral stationary phases and preliminary studies on their enantiomer separating ability for chiral protonated primary aralkylamines. ACTA ACUST UNITED AC 2012. [DOI: 10.1016/j.tetasy.2012.04.008] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
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9
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Barış D, Şeker S, Hoşgören H, Toğrul M. Synthesis of rigid and C2-symmetric 18-crown-6 type macrocycles bearing diamide–diester groups: enantiomeric recognition for α-(1-naphthyl)ethylammonium perchlorate salts. ACTA ACUST UNITED AC 2010. [DOI: 10.1016/j.tetasy.2010.05.051] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/19/2022]
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10
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Späth A, König B. Molecular recognition of organic ammonium ions in solution using synthetic receptors. Beilstein J Org Chem 2010; 6:32. [PMID: 20502608 PMCID: PMC2874414 DOI: 10.3762/bjoc.6.32] [Citation(s) in RCA: 159] [Impact Index Per Article: 11.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/17/2010] [Accepted: 03/09/2010] [Indexed: 01/12/2023] Open
Abstract
Ammonium ions are ubiquitous in chemistry and molecular biology. Considerable efforts have been undertaken to develop synthetic receptors for their selective molecular recognition. The type of host compounds for organic ammonium ion binding span a wide range from crown ethers to calixarenes to metal complexes. Typical intermolecular interactions are hydrogen bonds, electrostatic and cation-π interactions, hydrophobic interactions or reversible covalent bond formation. In this review we discuss the different classes of synthetic receptors for organic ammonium ion recognition and illustrate the scope and limitations of each class with selected examples from the recent literature. The molecular recognition of ammonium ions in amino acids is included and the enantioselective binding of chiral ammonium ions by synthetic receptors is also covered. In our conclusion we compare the strengths and weaknesses of the different types of ammonium ion receptors which may help to select the best approach for specific applications.
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Affiliation(s)
- Andreas Späth
- Institut für Organische Chemie, Universität Regensburg, D-93040 Regensburg, Germany, Phone: +49-943-941-4576, Fax: +49-943-941-1717
| | - Burkhard König
- Institut für Organische Chemie, Universität Regensburg, D-93040 Regensburg, Germany, Phone: +49-943-941-4576, Fax: +49-943-941-1717
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11
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Lämmerhofer M. Chiral recognition by enantioselective liquid chromatography: mechanisms and modern chiral stationary phases. J Chromatogr A 2009; 1217:814-56. [PMID: 19906381 DOI: 10.1016/j.chroma.2009.10.022] [Citation(s) in RCA: 511] [Impact Index Per Article: 34.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/07/2009] [Revised: 09/30/2009] [Accepted: 10/07/2009] [Indexed: 11/19/2022]
Abstract
An overview of the state-of-the-art in LC enantiomer separation is presented. This tutorial review is mainly focused on mechanisms of chiral recognition and enantiomer distinction of popular chiral selectors and corresponding chiral stationary phases including discussions of thermodynamics, additivity principle of binding increments, site-selective thermodynamics, extrathermodynamic approaches, methods employed for the investigation of dominating intermolecular interactions and complex structures such as spectroscopic methods (IR, NMR), X-ray diffraction and computational methods. Modern chiral stationary phases are discussed with particular focus on those that are commercially available and broadly used. It is attempted to provide the reader with vivid images of molecular recognition mechanisms of selected chiral selector-selectand pairs on basis of solid-state X-ray crystal structures and simulated computer models, respectively. Such snapshot images illustrated in this communication unfortunately cannot account for the molecular dynamics of the real world, but are supposed to be helpful for the understanding. The exploding number of papers about applications of various chiral stationary phases in numerous fields of enantiomer separations is not covered systematically.
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Affiliation(s)
- Michael Lämmerhofer
- Christian Doppler Laboratory for Molecular Recognition Materials, Department of Analytical Chemistry and Food Chemistry, University of Vienna, Waehringer Strasse 38, A-1090 Vienna, Austria.
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12
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Schnopp M, Haberhauer G. Highly Selective Recognition of α-Chiral Primary Organoammonium Ions byC3-Symmetric Peptide Receptors. European J Org Chem 2009. [DOI: 10.1002/ejoc.200900510] [Citation(s) in RCA: 29] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
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13
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Sunkur M, Baris D, Hosgoren H, Togrul M. Novel C2-Symmetric Macrocycles Bearing Diamide−Diester Groups: Synthesis and Enantiomeric Recognition for Primary Alkyl Ammonium Salts. J Org Chem 2008; 73:2570-5. [DOI: 10.1021/jo702210c] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Murat Sunkur
- Chemistry Department, University of Dicle, Faculty of Art and Science, 21280-Diyarbakır, Turkey
| | - Deniz Baris
- Chemistry Department, University of Dicle, Faculty of Art and Science, 21280-Diyarbakır, Turkey
| | - Halil Hosgoren
- Chemistry Department, University of Dicle, Faculty of Art and Science, 21280-Diyarbakır, Turkey
| | - Mahmut Togrul
- Chemistry Department, University of Dicle, Faculty of Art and Science, 21280-Diyarbakır, Turkey
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14
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Lakatos S, Fetter J, Bertha F, Huszthy P, Tóth T, Farkas V, Orosz G, Hollósi M. Preparation of a new chiral acridino-18-crown-6 ether-based stationary phase for enantioseparation of racemic protonated primary aralkyl amines. Tetrahedron 2008. [DOI: 10.1016/j.tet.2007.09.056] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/22/2022]
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15
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Farkas V, Tóth T, Orosz G, Huszthy P, Hollósi M. Enantioseparation of protonated primary arylalkylamines and amino acids containing an aromatic moiety on a pyridino-crown ether based new chiral stationary phase. ACTA ACUST UNITED AC 2006. [DOI: 10.1016/j.tetasy.2006.06.034] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/24/2022]
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16
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Hirose K, Yongzhu J, Nakamura T, Nishioka R, Ueshige T, Tobe Y. Preparation and evaluation of a chiral stationary phase covalently bound with chiral pseudo-1 8-crown-6 ether having 1-phenyl-1,2-cyclohexanediol as a chiral unit. J Chromatogr A 2005; 1078:35-41. [PMID: 16007979 DOI: 10.1016/j.chroma.2005.04.071] [Citation(s) in RCA: 29] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
A chiral stationary phase (CSP) has been prepared by chemically bonding a chiral pseudo-18-crown-6 type host having a 1-phenyl-1,2-cyclohexanediol unit to 3-aminopropyl silica gel. The chiral column was prepared by the slurry-packing method in a stainless steel HPLC column. Normal mobile phases can be used with this CSP in contrast to conventional dynamic coating type CSPs. Enantiomers of 20 out of 30 amino compounds, including 20 amino acids, 2 amino acid methyl esters, 6 amino alcohols, and 2 lipophilic amines, were efficiently separated on columns with this CSP. It is noteworthy that 15 amino compounds out of 30 were separated with better separation factors and shorter retention times compared to the corresponding CSP having pseudo-18-crown-6 with 1-phenyl-1,2-ethanediol as a chiral unit. In view of the correlation between the enantiomer selectivities observed in chromatography and those obtained in gas phase FABMS-EL methods and solution phase titrations, chiral recognition in the host-guest interaction likely contributes to enantiomer separation.
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Affiliation(s)
- Keiji Hirose
- Division of Frontier Materials Science, Graduate School of Engineering Science, Osaka University, 1-3 Machikaneyama, Toyonaka, Osaka 560-8531, Japan.
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Hirose K, Yongzhu J, Nakamura T, Nishioka R, Ueshige T, Tobe Y. Chiral stationary phase covalently bound with a chiral pseudo-18-crown-6 ether for enantiomer separation of amino compounds using a normal mobile phase. Chirality 2005; 17:142-8. [PMID: 15704196 DOI: 10.1002/chir.20138] [Citation(s) in RCA: 45] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
Abstract
In order to apply the excellent chiral recognition ability of chiral pseudo-18-crown-6 ethers that we developed to chiral separation, we prepared a chiral stationary phase (CSP) by immobilizing a chiral pseudo-18-crown-6-type host on 3-aminopropyl silica gel. A chiral column was prepared by the slurry-packing method in a stainless steel HPLC column. A liquid chromatography system using this CSP combined with the detection by mass spectrometry was used for enantiomer separation of amino compounds. A normal mobile phase can be used on this CSP as opposed to conventional dynamic coating-type CSPs. Enantiomers of 18 common natural amino acids were efficiently separated. The chiral separation observed for amino acid methyl esters, amino alcohols, and lipophilic amines was fair using this HPLC system. In view of the correlation between the enantiomer selectivity observed in chromatography and the complexion in solution, the chiral recognition in host-guest interactions might contribute to this enantiomer separation.
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Affiliation(s)
- Keiji Hirose
- Division of Frontier Materials Science, Graduate School of Engineering Science, Osaka University, Osaka, Japan
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Szalay L, Farkas V, Vass E, Hollósi M, Móczár I, Pintér Á, Huszthy P. Synthesis and selective lead(II) binding of achiral and enantiomerically pure chiral acridono-18-crown-6 ether type ligands. ACTA ACUST UNITED AC 2004. [DOI: 10.1016/j.tetasy.2004.03.024] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
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Synthesis of new optically active pyridino- and pyridono-18-crown-6 type ligands containing four lipophilic chains. ACTA ACUST UNITED AC 2003. [DOI: 10.1016/s0957-4166(03)00590-1] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
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Farkas V, Szalay L, Vass E, Hollósi M, Horváth G, Huszthy P. Probing the discriminating power of chiral crown hosts by CD spectroscopy. Chirality 2003; 15 Suppl:S65-73. [PMID: 12884376 DOI: 10.1002/chir.10271] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
Abstract
The discriminating efficiency of pyridino- (1), pyridono- and thiopyridono- (2), phenazino- (3), and acridino- (4) 18-crown-6 hosts as well as pyridino- (1) and phenazino- (3) 18-crown-6 hosts with allylic moieties attached either to the macrocyclic ring [X=CH-CH(2)-CH=CH(2) or C(CH(2)-CH=CH(2))(2)] or to the heterocyclic subunit was probed by circular dichroism (CD) spectroscopy using enantiomers of alpha-(1-naphthyl)- ethylamine hydrogen perchlorate (1-NEA). The CD spectra of the diastereomeric complexes as well as the difference and sum of the spectra were analyzed. Titration experiments were also performed monitored by CD or UV spectroscopy. The CD- and (1)H NMR-based enantiomeric preferences were compared. CD spectroscopy showed that the relative stability of heterochiral [(R,R)-host/(S)-guest or (S,S)-host/(R)-guest] complexes generally exceeds that of homochiral [(R,R)/(R)-or (S,S)/(S)] complexes. Bulkier substituents (R=iBu, sBu or tBu) decrease complex stability but increase the discriminating power of the host. According to (1)H NMR titration, attachment of one allylic linker group in position X of the macro ring [(S,S)-1b, (S,S)-1e] changes the discriminating preference (from heterochiral to homochiral) of the parent hosts (S,S)-1a and (S,S)-1d. This change of discriminating preference was not reflected in the CD spectra. Host (S,S)-1g with an allyloxy linker group in position gamma of the pyridine ring gives CD spectra which clearly reflect the high discriminating power and enantiomeric preference of the host. The exciton-coupled circular dichroism (ECCD) spectra of the 1-NEA complexes of phenazino and acridino hosts allow reliable determination of the enantiomeric preference by comparing the A values of the exciton couplets. An allylic group appended to the macrocyclic ring or the N-containing heterocyclic subunit allows for the attachment of the chiral discriminator to the solid matrix of a chromatographic sorbent and also serves as a spectroscopic label of the host. CD spectroscopy is a simple and rapid method, providing qualitative information on enantiomeric discrimination. It can be of great help in designing and testing new host molecules.
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Affiliation(s)
- Viktor Farkas
- Department of Organic Chemistry, Eötvös Loránd University, Budapest, Hungary
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21
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Hirose K, Nakamura T, Nishioka R, Ueshige T, Tobe Y. Preparation and evaluation of novel chiral stationary phases covalently bound with chiral pseudo-18-crown-6 ethers. Tetrahedron Lett 2003. [DOI: 10.1016/s0040-4039(03)00020-0] [Citation(s) in RCA: 17] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
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