1
|
Krait S, Salgado A, Villani C, Naumann L, Neusüß C, Chankvetadze B, Scriba GK. Unusual complexation behavior between daclatasvir and γ-Cyclodextrin. A multiplatform study. J Chromatogr A 2020; 1628:461448. [DOI: 10.1016/j.chroma.2020.461448] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/19/2020] [Revised: 07/30/2020] [Accepted: 08/01/2020] [Indexed: 12/14/2022]
|
2
|
Hok L, BoŽičević L, Sremec H, Šakić D, Vrček V. Racemization of oxazepam and chiral 1,4-benzodiazepines. DFT study of the reaction mechanism in aqueous solution. Org Biomol Chem 2019; 17:1471-1479. [PMID: 30676597 DOI: 10.1039/c8ob02991a] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/25/2023]
Abstract
The tranquilizer and hypnotic drug oxazepam undergoes the racemization process in aqueous medium, which is relevant for its pharmacological profile. The experimental barrier value (ΔG‡298 ≈ 91 kJ mol-1) was determined earlier, but the exact mechanism of enantiomerization is not known. Four different mechanisms have been proposed in the literature: C3-H/H exchange reaction, keto-enol tautomerization, solvolytic identity reaction, and ring-chain tautomerization. However, none of the reported reactions has been confirmed as the main pathway for racemization. In this work, all these mechanisms were subjected to comprehensive analysis performed by high-level quantum-chemical models. Two density functionals (B3LYP and M062X) were employed for geometry optimization of all stationary points at the corresponding potential surfaces, and the double-hybrid model (B2PLYP) was used for improved energy calculations. Out of all the tested mechanisms, only the ring-chain tautomerism fits the two experimental targets: the measured energy barrier and the pH-rate profile of racemization. The latter reveals that no acid/base catalysis is required for racemization to occur. The ring-chain tautomerism is initiated by intramolecular proton transfer from the C3-hydroxyl group to the imine nitrogen, which triggers the benzodiazepine ring opening and the formation of the achiral aldehyde intermediate. The latter undergoes ring closure which results in the inverted configuration at the C3-chiral atom of oxazepam. Our computational results suggest that the same mechanism is operative in the fast racemization of different 1,4-benzodiazepines, which posses the hydroxyl group at the stereogenic C3-centre (e.g. lorazepam or temazepam). In other benzodiazepine members (e.g. cinazepam or camazepam) the keto-enol tautomerization and/or the C3-H/H exchange mechanism may become relevant for their much slower racemization. This computational study is not only revealing in terms of mechanistic details, but also has predictive power for optical stability estimates in the family of benzodiazepines and similar heterocycles.
Collapse
Affiliation(s)
- Lucija Hok
- Faculty of Pharmacy and Biochemistry, University of Zagreb, Ante Kovačića 1, 10000 Zagreb, Croatia.
| | | | | | | | | |
Collapse
|
3
|
Pizzolato S, Štacko P, Kistemaker JCM, van Leeuwen T, Otten E, Feringa BL. Central-to-Helical-to-Axial-to-Central Transfer of Chirality with a Photoresponsive Catalyst. J Am Chem Soc 2018; 140:17278-17289. [PMID: 30458108 PMCID: PMC6326533 DOI: 10.1021/jacs.8b10816] [Citation(s) in RCA: 42] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/11/2018] [Indexed: 12/26/2022]
Abstract
Recent advances in molecular design have displayed striking examples of dynamic chirality transfer between various elements of chirality, e.g., from central to either helical or axial chirality and vice versa. While considerable progress in atroposelective synthesis has been made, it is intriguing to design chiral molecular switches able to provide selective and dynamic control of axial chirality with an external stimulus to modulate stereochemical functions. Here, we report the synthesis and characterization of a photoresponsive bis(2-phenol)-substituted molecular switch 1. The unique design exhibits a dynamic hybrid central-helical-axial transfer of chirality. The change of preferential axial chirality in the biaryl motif is coupled to the reversible switching of helicity of the overcrowded alkene core, dictated by the fixed stereogenic center. The potential for dynamic control of axial chirality was demonstrated by using ( R)-1 as switchable catalyst to direct the stereochemical outcome of the catalytic enantioselective addition of diethylzinc to aromatic aldehydes, with successful reversal of enantioselectivity for several substrates.
Collapse
Affiliation(s)
- Stefano
F. Pizzolato
- Center for Systems Chemistry, Stratingh
Institute for Chemistry and Zernike Institute for Advanced Materials,
Faculty of Mathematics and Natural Sciences, University of Groningen, Nijenborgh 4, 9747 AG Groningen, The Netherlands
| | - Peter Štacko
- Center for Systems Chemistry, Stratingh
Institute for Chemistry and Zernike Institute for Advanced Materials,
Faculty of Mathematics and Natural Sciences, University of Groningen, Nijenborgh 4, 9747 AG Groningen, The Netherlands
| | - Jos C. M. Kistemaker
- Center for Systems Chemistry, Stratingh
Institute for Chemistry and Zernike Institute for Advanced Materials,
Faculty of Mathematics and Natural Sciences, University of Groningen, Nijenborgh 4, 9747 AG Groningen, The Netherlands
| | - Thomas van Leeuwen
- Center for Systems Chemistry, Stratingh
Institute for Chemistry and Zernike Institute for Advanced Materials,
Faculty of Mathematics and Natural Sciences, University of Groningen, Nijenborgh 4, 9747 AG Groningen, The Netherlands
| | - Edwin Otten
- Center for Systems Chemistry, Stratingh
Institute for Chemistry and Zernike Institute for Advanced Materials,
Faculty of Mathematics and Natural Sciences, University of Groningen, Nijenborgh 4, 9747 AG Groningen, The Netherlands
| | - Ben L. Feringa
- Center for Systems Chemistry, Stratingh
Institute for Chemistry and Zernike Institute for Advanced Materials,
Faculty of Mathematics and Natural Sciences, University of Groningen, Nijenborgh 4, 9747 AG Groningen, The Netherlands
| |
Collapse
|
4
|
Perovani IS, de Oliveira ARM. Determination of Ethofumesate-2-hydroxy Stereolability by Dynamic HPLC. SEPARATION SCIENCE PLUS 2018. [DOI: 10.1002/sscp.201800112] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
Affiliation(s)
- Icaro Salgado Perovani
- Departamento de Química; Faculdade de Filosofia; Ciências e Letras de Ribeirão Preto; Universidade de São Paulo; Ribeirão Preto SP Brazil
| | | |
Collapse
|
5
|
Sepsey A, Németh DR, Németh G, Felinger A. Rate constant determination of interconverting enantiomers by chiral chromatography using a stochastic model. J Chromatogr A 2018; 1564:155-162. [DOI: 10.1016/j.chroma.2018.06.014] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/15/2018] [Revised: 06/03/2018] [Accepted: 06/05/2018] [Indexed: 11/29/2022]
|
6
|
Wong YF, Kulsing C, Marriott PJ. Switchable Enantioselective Three- and Four-Dimensional Dynamic Gas Chromatography–Mass Spectrometry: Example Study of On-Column Molecular Interconversion. Anal Chem 2017; 89:5620-5628. [DOI: 10.1021/acs.analchem.7b00853] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Yong Foo Wong
- Australian Centre for Research
on Separation Science, School of Chemistry, Monash University, Wellington Road, Clayton, Victoria 3800, Australia
| | - Chadin Kulsing
- Australian Centre for Research
on Separation Science, School of Chemistry, Monash University, Wellington Road, Clayton, Victoria 3800, Australia
| | - Philip J. Marriott
- Australian Centre for Research
on Separation Science, School of Chemistry, Monash University, Wellington Road, Clayton, Victoria 3800, Australia
| |
Collapse
|
7
|
Qamar S, Bibi S, Akram N, Seidel-Morgenstern A. Analysis of Two-Component Non-Equilibrium Model of Linear Reactive Chromatography. Chromatographia 2017. [DOI: 10.1007/s10337-017-3248-8] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
|
8
|
Suissa MR, Cohen S, Pogodin S, Agranat I. Heteromerous Bistricyclic Aromatic Enes: Dynamic Stereochemistry of Xanthylidene-Anthrones. Chirality 2015; 27:919-28. [PMID: 26425788 DOI: 10.1002/chir.22500] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/03/2015] [Revised: 07/09/2015] [Accepted: 07/20/2015] [Indexed: 11/08/2022]
Abstract
The heteromerous bistricyclic aromatic ene (BAE) 2,2'-dimethyl-10-(9H-xanthylidene)-9(10H)-anthrone (DMXA) was synthesized by a condensation of 10,10-dichloro-2-methylxanthene with 2-methylanthrone. X-ray crystallography of (E)-DMXA and xanthylidene-anthrone (XA) indicated that the molecules adopt anti-folded conformations with folding dihedral angles of 44°/44° and 39°/41°, respectively. The crystal structure of anti-folded (E)-DMXA does not indicate any xanthenylium-anthracenolate push-pull effect. E,Z-diastereomerization of DMXA was studied by (1) H-NMR coalescence-temperature measurements at different magnetic field strengths and by kinetic equilibration experiments. Free energy of activation for this process was 81.5 (±1.3) kJ/mol. B3LYP/6-311+G(d,p) calculations showed that anti-folded conformers of XA, (E)-DMXA, bianthrone (AA), and dixanthylene (XX) were global minima. The twisted conformers of XA, AA, and XX were local minima (ΔG298 = 16, 18, and 24 kJ/mol) with a substantial dipolar xanthenylium-anthracenolate dipolar contribution for XA. Chirality 27:919-928, 2015. © 2015 Wiley Periodicals, Inc.
Collapse
Affiliation(s)
- M Rachel Suissa
- Oslo and Akershus University College of Applied Sciences, Faculty of Health Sciences, Institute of Pharmacy and Bioengineering, Oslo, Norway
| | - Shmuel Cohen
- Organic Chemistry, Institute of Chemistry, The Hebrew University of Jerusalem, Jerusalem, Israel
| | - Sergey Pogodin
- Organic Chemistry, Institute of Chemistry, The Hebrew University of Jerusalem, Jerusalem, Israel
| | - Israel Agranat
- Organic Chemistry, Institute of Chemistry, The Hebrew University of Jerusalem, Jerusalem, Israel
| |
Collapse
|
9
|
Lindamulage De Silva A, Risso V, Jean M, Giorgi M, Monnier V, Naubron JV, Vanthuyne N, Farran D, Roussel C. A forgotten chiral spiro compound revisited: 3,3'-dimethyl-3H,3'H-2,2'-spirobi[[1,3]benzothiazole]. Chirality 2015; 27:716-21. [PMID: 26415851 DOI: 10.1002/chir.22492] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/14/2015] [Revised: 07/06/2015] [Accepted: 07/09/2015] [Indexed: 11/09/2022]
Abstract
The title compound was obtained as a side product during dimerization-oxidation steps of the carbene generated from N-methylbenzothiazolium iodide. Chromatography on (S,S)-Whelk O1 column showed on cooling a typical plateau shape chromatogram indicating an exchange between two enantiomers on the column. The thermal barrier to racemization was determined (85 kJ.mol(-1) at 10 °C) by dynamic high-performance liquid chromatography (DHPLC).The absolute configuration of the first (M) and second eluted (P) enantiomers on the (S, S)-Whelk O1 column was established by comparing the reconstructed circular dichroism (CD) spectra from the CD detector signal and the calculated CD spectrum of the (P) enantiomer. Mass spectrometry revealed that 3,3'-dimethyl-3H,3'H-2,2'-spirobi[[1,3]benzothiazole] can be viewed as a masked thiophenate attached to a benzothiazolium framework.
Collapse
Affiliation(s)
| | - Vesna Risso
- Aix Marseille Université, Centrale Marseille, CNRS, iSm2 UMR 7313, 13397, Marseille, France
| | - Marion Jean
- Aix Marseille Université, Centrale Marseille, CNRS, iSm2 UMR 7313, 13397, Marseille, France
| | - Michel Giorgi
- Spectropôle, Aix Marseille Université, Marseille, France
| | | | | | - Nicolas Vanthuyne
- Aix Marseille Université, Centrale Marseille, CNRS, iSm2 UMR 7313, 13397, Marseille, France
| | - Daniel Farran
- Aix Marseille Université, Centrale Marseille, CNRS, iSm2 UMR 7313, 13397, Marseille, France
| | - Christian Roussel
- Aix Marseille Université, Centrale Marseille, CNRS, iSm2 UMR 7313, 13397, Marseille, France
| |
Collapse
|
10
|
Stockinger S, Gmeiner J, Zawatzky K, Troendlin J, Trapp O. From stereodynamics to high-throughput screening of catalysed reactions. Chem Commun (Camb) 2014; 50:14301-9. [DOI: 10.1039/c4cc04892j] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/28/2022]
Abstract
In this review we summarised recent developments in high-throughput kinetic monitoring of reactions including the dynamics of interconverting stereoisomers and the simultaneous combination of (catalysed) reactions with chemical analysis in on-column reaction chromatographic devices.
Collapse
Affiliation(s)
- Skrollan Stockinger
- Organisch-Chemisches Institut
- Ruprecht-Karls-Universität Heidelberg
- 69120 Heidelberg, Germany
| | - Julia Gmeiner
- Organisch-Chemisches Institut
- Ruprecht-Karls-Universität Heidelberg
- 69120 Heidelberg, Germany
| | - Kerstin Zawatzky
- Organisch-Chemisches Institut
- Ruprecht-Karls-Universität Heidelberg
- 69120 Heidelberg, Germany
| | - Johannes Troendlin
- Organisch-Chemisches Institut
- Ruprecht-Karls-Universität Heidelberg
- 69120 Heidelberg, Germany
| | - Oliver Trapp
- Organisch-Chemisches Institut
- Ruprecht-Karls-Universität Heidelberg
- 69120 Heidelberg, Germany
| |
Collapse
|
11
|
Maier F, Trapp O. The Stereodynamics of 5,5’-Disubstituted BIPHEPs. Chirality 2012; 25:126-32. [DOI: 10.1002/chir.22125] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/26/2012] [Accepted: 09/21/2012] [Indexed: 11/07/2022]
Affiliation(s)
- Frank Maier
- Ruprecht-Karls-Universität Heidelberg, Organisch-Chemisches Institut; Im Neuenheimer Feld 270 69120 Heidelberg Germany
| | - Oliver Trapp
- Ruprecht-Karls-Universität Heidelberg, Organisch-Chemisches Institut; Im Neuenheimer Feld 270 69120 Heidelberg Germany
| |
Collapse
|
12
|
Tian C, Xiu P, Meng Y, Zhao W, Wang Z, Zhou R. Enantiomerization mechanism of thalidomide and the role of water and hydroxide ions. Chemistry 2012; 18:14305-13. [PMID: 23065668 DOI: 10.1002/chem.201202651] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/25/2012] [Indexed: 11/07/2022]
Abstract
The significance of the molecular chirality of drugs has been widely recognized due to the thalidomide tragedy. Most of the new drugs reaching the market today are single enantiomers, rather than racemic mixtures. However, many optically pure drugs, including thalidomide, undergo enantiomerization in vivo, thus negating the single enantiomers' benefits or inducing unexpected effects. A detailed atomic level understanding of chiral conversion, which is still largely lacking, is thus critical for drug development. Herein, we use first-principle density function theory (DFT) to explore the mechanism of enantiomerization of thalidomide. We have identified the two most plausible interconversion pathways for isolated thalidomide: 1) proton transfer from the chiral carbon center to an adjacent carbonyl oxygen atom, followed by isomerization and rotation of the glutarimide ring (before the proton hops back to the chiral carbon atom); and 2) a pathway that is the same as "1", but with the isomerization of the glutarimide ring occurring ahead of the initial proton transfer reaction. There are two remarkable energy barriers, 73.29 and 23.59 kcal mol(-1), corresponding to the proton transfer and the rotation of the glutarimide ring, respectively. Furthermore, we found that water effectively catalyzes the interconversion by facilitating the proton transfer with the highest energy barrier falling to approximately 30 kcal mol(-1), which, to our knowledge, is the first time that this important role of water in chiral conversion has been demonstrated. Finally, we show that the hydroxide ion can further lower the enantiomerization energy barrier to approximately 24 kcal mol(-1) by facilitating proton abstraction, which agrees well with recent experimental data under basic conditions. Our current findings highlight the importance of water and hydroxide ions in the enantiomerization of thalidomide and also provide new insights into the mechanism of enantiomerization at an atomic level.
Collapse
Affiliation(s)
- Chuanjin Tian
- Institute of Atomic and Molecular Physics, Jilin University, Changchun 130012, PR China
| | | | | | | | | | | |
Collapse
|
13
|
Chiral HPLC studies on chemical behavior of 6-methoxydihydrosanguinarine in alcoholic solvent system. J Pharm Biomed Anal 2011; 56:479-83. [DOI: 10.1016/j.jpba.2011.06.002] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/08/2010] [Revised: 06/04/2011] [Accepted: 06/05/2011] [Indexed: 11/17/2022]
|
14
|
Trapp O. Investigation of the stereodynamics of molecules and catalyzed reactions by CE. Electrophoresis 2010; 31:786-813. [DOI: 10.1002/elps.200900599] [Citation(s) in RCA: 34] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
|
15
|
Wu E, Jung SH, Chen J, Kim YH, Park KL, Lee W, Kang JS. Racemization of 6-methoxydihydrosanguinarine in methanol investigated by enantioselective dynamic HPLC. J Pharm Biomed Anal 2010; 51:103-6. [DOI: 10.1016/j.jpba.2009.08.014] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/19/2009] [Revised: 08/04/2009] [Accepted: 08/10/2009] [Indexed: 10/20/2022]
|
16
|
Demir-Ordu O, Dogan I. Axially chiral N-(o-aryl)-4-hydroxy-2-oxazolidinone derivatives from diastereoselective reduction of N-(o-aryl)-2,4-oxazolidinediones: thermally interconvertible atropisomers via ring-chain-ring tautomerization. Chirality 2009; 22:641-54. [PMID: 20014036 DOI: 10.1002/chir.20811] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Abstract
The reduction of the axially chiral N-(o-aryl)-5,5-dimethyl-2,4-oxazolidinediones by NaBH(4) yielded axially chiral N-(o-aryl)-4-hydroxy-5,5-dimethyl-2-oxazolidinone enantiomers having a chiral center at C-4, with 100% diastereoselectivity as has been shown by their (1)H and (13)C NMR spectra and by enantioselective HPLC analysis. The resolved enantiomeric isomers were found to interconvert thermally through an aldehyde intermediate formed upon ring cleavage via a latent ring-chain-ring tautomerization. It was found that the rate of enantiomerization depended on the size and the electronic effect of the ortho substituent present on the aryl ring bonded to the nitrogen of the heterocycle.
Collapse
Affiliation(s)
- Oznur Demir-Ordu
- Department of Chemistry, Bogaziçi University, Bebek, 34342, Istanbul, Turkey
| | | |
Collapse
|
17
|
Ciogli A, Dalla Cort A, Gasparrini F, Lunazzi L, Mandolini L, Mazzanti A, Pasquini C, Pierini M, Schiaffino L, Mihan FY. Enantiomerization of Chiral Uranyl−Salophen Complexes via Unprecedented Ligand Hemilability: Toward Configurationally Stable Derivatives. J Org Chem 2008; 73:6108-18. [DOI: 10.1021/jo800610f] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Alessia Ciogli
- Dipartimento di Chimica and IMC-CNR Sezione Meccanismi di Reazione, Università La Sapienza, Box 34 Roma 62, 00185 Roma, Italy, Dipartimento di Studi di Chimica e Tecnologia delle Sostanze Biologicamente Attive, Università La Sapienza, Piazzale Aldo Moro 5, 00185 Roma, Italy, and Dipartimento di Chimica Organica “A Mangini”, Università di Bologna, Viale Risorgimento 4, 40136 Bologna
| | - Antonella Dalla Cort
- Dipartimento di Chimica and IMC-CNR Sezione Meccanismi di Reazione, Università La Sapienza, Box 34 Roma 62, 00185 Roma, Italy, Dipartimento di Studi di Chimica e Tecnologia delle Sostanze Biologicamente Attive, Università La Sapienza, Piazzale Aldo Moro 5, 00185 Roma, Italy, and Dipartimento di Chimica Organica “A Mangini”, Università di Bologna, Viale Risorgimento 4, 40136 Bologna
| | - Francesco Gasparrini
- Dipartimento di Chimica and IMC-CNR Sezione Meccanismi di Reazione, Università La Sapienza, Box 34 Roma 62, 00185 Roma, Italy, Dipartimento di Studi di Chimica e Tecnologia delle Sostanze Biologicamente Attive, Università La Sapienza, Piazzale Aldo Moro 5, 00185 Roma, Italy, and Dipartimento di Chimica Organica “A Mangini”, Università di Bologna, Viale Risorgimento 4, 40136 Bologna
| | - Lodovico Lunazzi
- Dipartimento di Chimica and IMC-CNR Sezione Meccanismi di Reazione, Università La Sapienza, Box 34 Roma 62, 00185 Roma, Italy, Dipartimento di Studi di Chimica e Tecnologia delle Sostanze Biologicamente Attive, Università La Sapienza, Piazzale Aldo Moro 5, 00185 Roma, Italy, and Dipartimento di Chimica Organica “A Mangini”, Università di Bologna, Viale Risorgimento 4, 40136 Bologna
| | - Luigi Mandolini
- Dipartimento di Chimica and IMC-CNR Sezione Meccanismi di Reazione, Università La Sapienza, Box 34 Roma 62, 00185 Roma, Italy, Dipartimento di Studi di Chimica e Tecnologia delle Sostanze Biologicamente Attive, Università La Sapienza, Piazzale Aldo Moro 5, 00185 Roma, Italy, and Dipartimento di Chimica Organica “A Mangini”, Università di Bologna, Viale Risorgimento 4, 40136 Bologna
| | - Andrea Mazzanti
- Dipartimento di Chimica and IMC-CNR Sezione Meccanismi di Reazione, Università La Sapienza, Box 34 Roma 62, 00185 Roma, Italy, Dipartimento di Studi di Chimica e Tecnologia delle Sostanze Biologicamente Attive, Università La Sapienza, Piazzale Aldo Moro 5, 00185 Roma, Italy, and Dipartimento di Chimica Organica “A Mangini”, Università di Bologna, Viale Risorgimento 4, 40136 Bologna
| | - Chiara Pasquini
- Dipartimento di Chimica and IMC-CNR Sezione Meccanismi di Reazione, Università La Sapienza, Box 34 Roma 62, 00185 Roma, Italy, Dipartimento di Studi di Chimica e Tecnologia delle Sostanze Biologicamente Attive, Università La Sapienza, Piazzale Aldo Moro 5, 00185 Roma, Italy, and Dipartimento di Chimica Organica “A Mangini”, Università di Bologna, Viale Risorgimento 4, 40136 Bologna
| | - Marco Pierini
- Dipartimento di Chimica and IMC-CNR Sezione Meccanismi di Reazione, Università La Sapienza, Box 34 Roma 62, 00185 Roma, Italy, Dipartimento di Studi di Chimica e Tecnologia delle Sostanze Biologicamente Attive, Università La Sapienza, Piazzale Aldo Moro 5, 00185 Roma, Italy, and Dipartimento di Chimica Organica “A Mangini”, Università di Bologna, Viale Risorgimento 4, 40136 Bologna
| | - Luca Schiaffino
- Dipartimento di Chimica and IMC-CNR Sezione Meccanismi di Reazione, Università La Sapienza, Box 34 Roma 62, 00185 Roma, Italy, Dipartimento di Studi di Chimica e Tecnologia delle Sostanze Biologicamente Attive, Università La Sapienza, Piazzale Aldo Moro 5, 00185 Roma, Italy, and Dipartimento di Chimica Organica “A Mangini”, Università di Bologna, Viale Risorgimento 4, 40136 Bologna
| | - Francesco Yafteh Mihan
- Dipartimento di Chimica and IMC-CNR Sezione Meccanismi di Reazione, Università La Sapienza, Box 34 Roma 62, 00185 Roma, Italy, Dipartimento di Studi di Chimica e Tecnologia delle Sostanze Biologicamente Attive, Università La Sapienza, Piazzale Aldo Moro 5, 00185 Roma, Italy, and Dipartimento di Chimica Organica “A Mangini”, Università di Bologna, Viale Risorgimento 4, 40136 Bologna
| |
Collapse
|
18
|
Felinger A. Molecular dynamic theories in chromatography. J Chromatogr A 2008; 1184:20-41. [DOI: 10.1016/j.chroma.2007.12.066] [Citation(s) in RCA: 45] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/11/2007] [Revised: 12/10/2007] [Accepted: 12/20/2007] [Indexed: 10/22/2022]
|
19
|
Felix G, Berthod A. Part II: From Dermatologicals to Sensory Organ and Various Drugs. SEPARATION AND PURIFICATION REVIEWS 2008. [DOI: 10.1080/15422110701873007] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/22/2022]
|
20
|
Fedurcová A, Lehotay J, Liptaj T, Prónayová N, Čižmárik J. HPLC Separation of Diazepam Conformers Coupled with Off‐Line NMR Experiment. J LIQ CHROMATOGR R T 2007. [DOI: 10.1080/10826070600598852] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/24/2022]
Affiliation(s)
- Andrea Fedurcová
- a Department of Analytical Chemistry, Faculty of Chemical and Food Technology , Slovak University of Technology , Bratislava, Slovakia
| | - Jozef Lehotay
- a Department of Analytical Chemistry, Faculty of Chemical and Food Technology , Slovak University of Technology , Bratislava, Slovakia
| | - Tibor Liptaj
- b Central Laboratory, Faculty of Chemical and Food Technology , Slovak University of Technology , Bratislava, Slovakia
| | - Nad'a Prónayová
- b Central Laboratory, Faculty of Chemical and Food Technology , Slovak University of Technology , Bratislava, Slovakia
| | - Jozef Čižmárik
- c Department of Pharmaceutical Chemistry, Faculty of Pharmacy , Commenius University , Bratislava, Slovakia
| |
Collapse
|
21
|
D'Acquarica I, Gasparrini F, Pierini M, Villani C, Zappia G. Dynamic HPLC on chiral stationary phases: A powerful tool for the investigation of stereomutation processes. J Sep Sci 2006; 29:1508-16. [PMID: 16894796 DOI: 10.1002/jssc.200600129] [Citation(s) in RCA: 91] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
Abstract
Dynamic HPLC on enantioselective stationary phases has become a well-established technique to investigate chiral molecules with internal motions that result in stereoinversion and occur on the time scale of the separation process. Kinetic parameters for the on-column interconversion phenomena can be extracted from experimental peak profiles by computer simulation or by direct calculation methods. The technique has been used in a wide range of temperatures and is complementary in scope to dynamic NMR spectroscopy.
Collapse
Affiliation(s)
- Ilaria D'Acquarica
- Dipartimento di Studi di Chimica e Tecnologia delle Sostanze Biologicamente Attive, Università degli Studi di Roma La Sapienza, Rome, Italy
| | | | | | | | | |
Collapse
|
22
|
Ahmed KS, Tazerouti F, Badjah-Hadj-Ahmed AY, Meklati BY. Application of Native and Hydroxypropyl-Substituted β-Cyclodextrin Bonded Silica Gel as Stationary Phases for High Performance Liquid Chromatography. Chromatographia 2005. [DOI: 10.1365/s10337-005-0673-x] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
|
23
|
Trapp O, Shellie R, Marriott P, Schurig V. Simulation of Elution Profiles for Two-Dimensional Dynamic Gas Chromatographic Experiments. Anal Chem 2003; 75:4452-61. [PMID: 14632049 DOI: 10.1021/ac0301144] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
The interconversion of E and Z isomers of acetaldoxime 1 and butyraldoxime 2 have been investigated by comprehensive two-dimensional dynamic gas chromatography (DGCxDGC) and computer simulation. Time-resolved cryogenic modulation is capable of revealing the precise isomeric ratio as a fine structure under the dynamic elution profile, which is characterized in one-dimensional experiments by a plateau formation or peak coalescence caused by interconversion of the isomers during the separation process. The chromatographic theoretical plate model has been extended for the computer simulation of comprehensive two-dimensional dynamic chromatographic experiments. A novel program, ChromWin 2D, based on the new algorithm has been developed for computer simulation to evaluate and predict the elution profiles of DGCxDGC experiments. ChromWin 2D allows the determination of rate constants and barriers of isomerization, epimerization, and enantiomerization processes occurring during chromatographic separations. The Eyring activation parameters of the E/Z and Z/E isomerization barriers in the presence of the stationary phase BP21 (poly(ethylene glycol) terephthalate terminated) were determined by temperature-dependent experiments between 80 and 90 degrees C for 1 and 70 and 130 degrees C for 2. The thermodynamic Gibbs free energy of the E/Z equilibrium of the isomers has been determined from the time-resolved chromatograms by cryogenic modulation. The method described here constitutes a new and important tool for the determination of isomerization barriers, which are of great interest, for example, for the quantitative determination of derivatized aldehydes, such as dinitrophenylhydrazine derivatives, in trace analysis.
Collapse
Affiliation(s)
- Oliver Trapp
- Department of Chemistry, Stanford University, Stanford, California 94305-5080, USA.
| | | | | | | |
Collapse
|