1
|
Nguyen BT, Choi YJ, Kim KH, Song GY, Kim HM, Kang JS. Chiral separation and molecular modeling study of decursinol and its derivatives using polysaccharide-based chiral stationary phases. J Chromatogr A 2023; 1705:464165. [PMID: 37419019 DOI: 10.1016/j.chroma.2023.464165] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/01/2023] [Revised: 06/08/2023] [Accepted: 06/14/2023] [Indexed: 07/09/2023]
Abstract
Plant-based bioactive substances have long been used to treat inflammatory ailments, owing to their low toxicity and cost-effectiveness. To enhance plant treatment by eliminating undesirable isomers, optimizing the chiral separation techniques in pharmaceutical and clinical studies is important. This study reported a simple and effective method for chiral separation of decursinol and its derivatives, which are pyranocoumarin compounds with anti-cancer and anti-inflammatory properties. Baseline separation (Rs >1.5) was achieved using five different polysaccharide-based chiral stationary phases (CSPs) that differed in chiral origin, chiral selector chemistry, and preparation technique. To separate all six enantiomers simultaneously, n-hexane and three alcohol modifiers (ethanol, isopropanol, and n-butanol) were used as mobile phases in the normal-phase mode. The chiral separation ability of each column with various mobile phase compositions was compared and discussed. As a result, amylose-based CSPs with linear alcohol modifiers demonstrated superior resolution. Three cases of elution order reversal caused by modifications of CSPs and alcohol modifiers were observed and thoroughly analyzed. To elucidate the chiral recognition mechanism and enantiomeric elution order (EEO) reversal phenomenon, detailed molecular docking simulations were conducted. The R- and S-enantiomers of decursinol, epoxide, and CGK012 exhibited binding energies of -6.6, -6.3, -6.2, -6.3, -7.3, and -7.5 kcal/mol, respectively. The magnitude of the difference in binding energies was consistent with the elution order and enantioselectivity (α) of the analytes. The molecular simulation results demonstrated that hydrogen bonds, π-π interactions, and hydrophobic interactions have a significant impact on chiral recognition mechanisms. Overall, this study presented a novel and logical approach of optimizing chiral separation techniques in the pharmaceutical and clinical industries. Our findings could be further applied for screening and optimizing enantiomeric separation.
Collapse
Affiliation(s)
- Bao Tan Nguyen
- College of Pharmacy, Chungnam National University, Daejeon, Republic of Korea
| | - Yoon Jung Choi
- College of Pharmacy, Chungnam National University, Daejeon, Republic of Korea
| | - Kyeong Ho Kim
- College of Pharmacy, Kangwon National University, Gangwon-do, Republic of Korea
| | - Gyu Yong Song
- College of Pharmacy, Chungnam National University, Daejeon, Republic of Korea
| | - Hyung Min Kim
- College of Pharmacy, Chungnam National University, Daejeon, Republic of Korea.
| | - Jong Seong Kang
- College of Pharmacy, Chungnam National University, Daejeon, Republic of Korea.
| |
Collapse
|
2
|
Ali I, Boumoua N, Sekkoum K, Belboukhari N, Ghfar A, Ouladsmane M, AlJumah BA. A comparison of chiral resolution of antifungal agents on different polysaccharide chiral columns under various mobile phase modes: Application in the biological samples. J Chromatogr B Analyt Technol Biomed Life Sci 2021; 1175:122738. [PMID: 33992975 DOI: 10.1016/j.jchromb.2021.122738] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/09/2021] [Revised: 04/20/2021] [Accepted: 04/24/2021] [Indexed: 10/21/2022]
Abstract
The current article describes the chiral separation of tioconazole, miconazole, isoconazole, sertaconazole and terconazole, with Lux i-Cellulose 5 and Lux i-Amylose-1 chiral columns under organic polar, normal and reversed mobile phases modes. The mobile phase flow rate was 1 mL/min with 230 nm detection at 25 ± 1 °C temperature. The polar organic mobile phases offered certain advantages for separation such as short analysis time, order of elution, high plate numbers and favorable signal to noise ratio. The values of k, α and Rs were ranged from 0.6 to 7.87, 1.10 to 1.62 and 0.37 to 5.72 in polar organic, 0.15 to 43.86, 1.02 to 2.01 and 0.36 to 8.03 in normal, and 0.34 to 15.99, 1.03 to 1.40 and 0.59 to 4.18 in reversed phases modes, respectively. The reported methods were applied in urine samples and the results were satisfactory. The reported methods were applied to the analysis of urine samples.
Collapse
Affiliation(s)
- Imran Ali
- Department of Chemistry, Jamia Millia Islamia (A Central University), New Delhi 110025, India.
| | - Nadia Boumoua
- Bioactive Molecules and Chiral Separation Laboratory, Faculty of Exacts Sciences, University Tahri Mohamed of Bechar, Algeria
| | - Khaled Sekkoum
- Bioactive Molecules and Chiral Separation Laboratory, Faculty of Exacts Sciences, University Tahri Mohamed of Bechar, Algeria
| | - Nasser Belboukhari
- Bioactive Molecules and Chiral Separation Laboratory, Faculty of Exacts Sciences, University Tahri Mohamed of Bechar, Algeria
| | - Ayman Ghfar
- Advanced Materials Research Chair, Chemistry Department, College of Science, King Saud University, Riyadh 11451, Saudi Arabia
| | - Mohamed Ouladsmane
- Advanced Materials Research Chair, Chemistry Department, College of Science, King Saud University, Riyadh 11451, Saudi Arabia
| | - Bayan Ahmed AlJumah
- Department of Pharmaceutical Practice, College of Pharmacy, Princess Nourah bint Abdulrahman University, Riyadh 11671, Saudi Arabia
| |
Collapse
|
3
|
Liu Y, Wang X, Yu J, Guo X. Chiral separation and molecular simulation study of six antihistamine agents on a coated cellulose tri-(3,5-dimethylphenycarbamate) column (Chiralcel OD-RH) and its recognition mechanisms. Electrophoresis 2021; 42:1461-1472. [PMID: 33905565 DOI: 10.1002/elps.202100033] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/01/2021] [Revised: 03/10/2021] [Accepted: 04/05/2021] [Indexed: 11/07/2022]
Abstract
Enantiomeric separation of six antihistamine agents was first systematically investigated on a cellulose-based chiral stationary phase (CSP), that is, cellulose tris-(3,5-dimethyl phenyl carbamate) (Chiralcel OD-RH), under the reversed-phase mode. Orphenadrine, meclizine, terfenadine, dioxopromethazine, and carbinoxamine enantiomers were completely separated under the optimized mobile phase conditions with resolutions of 5.02, 1.93, 1.68, 1.67, and 1.54, respectively. Mequitazine was partially separated with a resolution of 0.77. The influences of type and concentration of buffer salt, the pH of buffer solution, and the type and ratio of organic modifier on the chiral separation were evaluated and optimized. For a better insight into the enantiorecognition mechanisms, molecular docking was carried out via the Autodock software. The lowest binding energy and the optimal conformations of the analytes/CSP complexes were supplied, and the mechanisms of chiral recognition were determined. According to the results, the key interactions for the chiral recognition of these six analytes on CDMPC were π-π interactions, hydrophobic interactions, hydrogen bond interactions, and some special interactions.
Collapse
Affiliation(s)
- Yanru Liu
- School of Pharmacy, Shenyang Pharmaceutical University, Shenyang, Liaoning Province, P. R. China
| | - Xia Wang
- School of Pharmacy, Shenyang Pharmaceutical University, Shenyang, Liaoning Province, P. R. China
| | - Jia Yu
- School of Pharmacy, Shenyang Pharmaceutical University, Shenyang, Liaoning Province, P. R. China
| | - Xingjie Guo
- School of Pharmacy, Shenyang Pharmaceutical University, Shenyang, Liaoning Province, P. R. China
| |
Collapse
|
4
|
Gogolashvili A, Lomsadze K, Chankvetadze L, Takaishvili N, Peluso P, Dallocchio R, Salgado A, Chankvetadze B. Separation of tetrahydrozoline enantiomers in capillary electrophoresis with cyclodextrin-type chiral selectors and investigation of chiral recognition mechanisms. J Chromatogr A 2021; 1643:462084. [PMID: 33789195 DOI: 10.1016/j.chroma.2021.462084] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/10/2021] [Revised: 03/16/2021] [Accepted: 03/19/2021] [Indexed: 12/13/2022]
Abstract
The recognition power and affinity pattern of various cyclodextrins (CD) towards the enantiomers of tetrahydrozoline (THZ) were studied using capillary electrophoresis (CE). As expected, affinity of THZ enantiomers and selectivity of recognition towards CD derivatives was strongly dependent on the cavity size and substituent type and pattern on the CD rims. Not only were the affinity strength and selectivity of recognition affected by the size of the cavity and chemistry of the CDs but also the affinity pattern. Another interesting example of opposite affinity pattern of enantiomers towards α- and β-CD was observed here. In addition, opposite affinity pattern of THZ enantiomers was seen towards β-CD and its acetylated derivatives, while methylation of β-CD did not affect the affinity pattern of THZ enantiomers. In order to get more information about structural mechanisms of the multivariate dependences mentioned above, rotating frame Overhauser enhancement spectroscopy (ROESY) and computation techniques were used. Significant differences between the structure of THZ complexes with different CDs with both methods were encountered. Good correlations between experimentally determined and computed structure of complexes, as well as between computed complex stabilities and enantiomer migration order (EMO) in CE were observed.
Collapse
Affiliation(s)
- Ann Gogolashvili
- Institute of Physical and Analytical Chemistry, School of Exact and Natural Sciences, Tbilisi State University, Chavchavadze Ave 3, Tbilisi 0179, Georgia
| | - Ketevan Lomsadze
- Institute of Physical and Analytical Chemistry, School of Exact and Natural Sciences, Tbilisi State University, Chavchavadze Ave 3, Tbilisi 0179, Georgia; School of Science and Technology, The University of Georgia, 77a, M. Kostava Str., Tbilisi 0171, Georgia
| | - Lali Chankvetadze
- Institute of Physical and Analytical Chemistry, School of Exact and Natural Sciences, Tbilisi State University, Chavchavadze Ave 3, Tbilisi 0179, Georgia
| | - Nino Takaishvili
- Institute of Physical and Analytical Chemistry, School of Exact and Natural Sciences, Tbilisi State University, Chavchavadze Ave 3, Tbilisi 0179, Georgia
| | - Paola Peluso
- Istituto di Chimica Biomolecolare ICB-CNR, Sede secondary a di Sassari, Traversa La Crucca 3, Regione Baldinca, Sassari, Li Punti 07100, Italy
| | - Roberto Dallocchio
- Istituto di Chimica Biomolecolare ICB-CNR, Sede secondary a di Sassari, Traversa La Crucca 3, Regione Baldinca, Sassari, Li Punti 07100, Italy
| | - Antonio Salgado
- NMR Spectroscopy Centre (CERMN), CAI Químicas, Faculty of Pharmacy, University of Alcalá, Alcalá de Henares, Madrid E-28805, Spain
| | - Bezhan Chankvetadze
- Institute of Physical and Analytical Chemistry, School of Exact and Natural Sciences, Tbilisi State University, Chavchavadze Ave 3, Tbilisi 0179, Georgia.
| |
Collapse
|
5
|
Tsui HW, Ye PW, Huang SX. Effect of solvents on the chiral recognition mechanisms of immobilized cellulose-based chiral stationary phase. J Chromatogr A 2020; 1637:461796. [PMID: 33387913 DOI: 10.1016/j.chroma.2020.461796] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/29/2020] [Revised: 12/07/2020] [Accepted: 12/08/2020] [Indexed: 02/06/2023]
Abstract
The effect of solvents on the enantioselectivities of four structurally similar chiral solutes with a cellulose derivative-based chiral stationary phase, Chiralpak IB, were studied using acetone (AC), 2-propanol (IPA), and tert-butanol (TBA) separately as polar modifiers. The enantioselectivities α of benzoin and methyl mandelate decrease with an increase in modifier concentration CM, whereas the enantioselectivity of pantolactone increased with increasing AC concentration. These results were attributed to the heterogeneous adsorption mechanisms of enantiomers. To interpret the dependence of enantioselectivity on modifier content, an enantioselectivity model based on a two-site adsorption model was proposed. The dependence of α on CM was inferred to be mainly due to the distinct modulating effects of modifier concentration on the two adsorption sites: the nonselective type-I site and enantioselective type-II site. The model fitted the benzoin data satisfactorily over a wide TBA concentration range. The retention factors as a function of TBA concentration were successfully deconvoluted for each site. With the use of the proposed model, it was inferred that the chiral recognitions of benzoin and methyl mandelate were mainly achieved by the presence of an aromatic group adjacent to the hydroxyl group. When using IPA and TBA separately as modifiers, the presence of an aromatic group adjacent to the ketone group mainly contributed to the nonselective π interactions and enantioselective steric interactions, respectively. These results, along with those of the modifier adsorption isotherms, determined using the perturbation method, as well as the retention behaviors of various achiral solutes, indicate that the molecular recognition mechanism of IB sorbent is highly sensitive to the adsorbate's molecular geometry. The molecular environment of the sorbent can be controlled using different modifiers, leading to distinct adsorption and retention mechanisms.
Collapse
Affiliation(s)
- Hung-Wei Tsui
- Department of Chemical Engineering and Biotechnology, National Taipei University of Technology, 1, Sec. 3, Zhongxiao E. Rd., Taipei 10608 Taiwan.
| | - Pei-Wen Ye
- Department of Chemical Engineering and Biotechnology, National Taipei University of Technology, 1, Sec. 3, Zhongxiao E. Rd., Taipei 10608 Taiwan
| | - Si-Xian Huang
- Department of Chemical Engineering and Biotechnology, National Taipei University of Technology, 1, Sec. 3, Zhongxiao E. Rd., Taipei 10608 Taiwan
| |
Collapse
|
6
|
Cai L, Xue M, Lun J, Li S, Yu J, Guo X. Enantioseparation and molecular modeling study of eight psychoactive drugs on a coated polysaccharide-based chiral stationary phase. Electrophoresis 2020; 41:2092-2101. [PMID: 32885849 DOI: 10.1002/elps.202000224] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/01/2020] [Revised: 08/28/2020] [Accepted: 08/30/2020] [Indexed: 01/28/2023]
Abstract
The enantioseparation of eight psychoactive drugs has been firstly performed on a coated cellulose-based chiral stationary phase (Chiralcel OJ-H). To obtain optimum separation conditions, the influences of alcohol modifiers and basic/acidic additives have been studied. As a result, except for the partial separation of oxybutynin enantiomers, the other seven drug enantiomers including mirtazapine, sulpiride, promethazine, citalopram, oxazepam, donepezil, and cyamemazine have been completely separated. Additionally, for gaining a better insight into the chiral recognition mechanisms, molecular docking was carried out using the Autodock software. Herein, binding energy and conformations of the chiral stationary phase complexes were provided, and it was found that the distinction in enantiomeric conformation determined the number and strength of intermolecular interactions between analytes and chiral stationary phase which resulted in the difference in binding energies of two enantiomers, and ultimately led to the different migration. These modeling results were in accordance with the observed enantioseparation results in high performance liquid chromatography experiments. At last, chiral separation mechanisms have been discussed in detail, and it has been confirmed that hydrogen bond, π-π, hydrophobic interactions, and some special interactions synergistically contributed to the enantioseparation of psychoactive drugs. This article is protected by copyright. All rights reserved.
Collapse
Affiliation(s)
- Liangzhao Cai
- School of Pharmacy, Shenyang Pharmaceutical University, Shenyang, Liaoning Province, P. R. China
| | - Mengyao Xue
- School of Pharmacy, Shenyang Pharmaceutical University, Shenyang, Liaoning Province, P. R. China
| | - Jia Lun
- School of Pharmacy, Shenyang Pharmaceutical University, Shenyang, Liaoning Province, P. R. China
| | - Shuang Li
- School of Pharmacy, Shenyang Pharmaceutical University, Shenyang, Liaoning Province, P. R. China
| | - Jia Yu
- School of Pharmacy, Shenyang Pharmaceutical University, Shenyang, Liaoning Province, P. R. China
| | - Xingjie Guo
- School of Pharmacy, Shenyang Pharmaceutical University, Shenyang, Liaoning Province, P. R. China
| |
Collapse
|
7
|
Yin C, Zhang J, Chang L, Zhang M, Yang T, Zhang X, Zhang J. Regioselectively substituted cellulose mixed esters synthesized by two-steps route to understand chiral recognition mechanism and fabricate high-performance chiral stationary phases. Anal Chim Acta 2019; 1073:90-98. [PMID: 31146840 DOI: 10.1016/j.aca.2019.04.071] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/23/2019] [Revised: 04/18/2019] [Accepted: 04/27/2019] [Indexed: 01/07/2023]
Abstract
It is challenging to design and fabricate new and high-performance cellulose-based chiral stationary phases (CSPs), due to the indistinct chiral recognition mechanism and the inherent difficulty to control the structure of cellulose derivatives. Herein, taking advantage of the high regioselective benzoylation of cellulose in 1-allyl-3-methylimidazolium chloride, a series of regioselectively substituted cellulose mixed esters, cellulose 6-benzoate-2,3-phenylcarbamate, are directly obtained by a facile two-steps route without protecting and deprotecting process. The resultant cellulose mixed esters exhibit high chiral recognition capability. In particular, when the benzoate group has an electron-donating substituent on phenyl ring, such as 4-tert-butyl group, the corresponding regioselectively substituted cellulose mixed esters have much better enantioseparation capability than cellulose tri(3,5-dimethylphenylcarbamate), which is commercially available as Chiralcel OD column, one of the most powerful CSPs. More importantly, via adjusting the chemical structure of cellulose derivatives and adding a post-treatment process to optimize their chiral recognition properties, the chiral recognition mechanism is clearly revealed. The synergy of the hydrophobic helical conformation, weak hydrogen-bond donating ability and appropriate distribution of substituents of cellulose derivatives is essential to fabricate high-performance CSPs.
Collapse
Affiliation(s)
- Chunchun Yin
- Beijing National Laboratory for Molecular Sciences, CAS Key Laboratory of Engineering Plastics, Institute of Chemistry, Chinese Academy of Sciences (CAS), Beijing, 100190, China; University of Chinese Academy of Sciences, Beijing, 100049, China
| | - Jinming Zhang
- Beijing National Laboratory for Molecular Sciences, CAS Key Laboratory of Engineering Plastics, Institute of Chemistry, Chinese Academy of Sciences (CAS), Beijing, 100190, China.
| | - Limin Chang
- Beijing National Laboratory for Molecular Sciences, CAS Key Laboratory of Engineering Plastics, Institute of Chemistry, Chinese Academy of Sciences (CAS), Beijing, 100190, China
| | - Mei Zhang
- Beijing Center for Physical and Chemical Analysis, Beijing Key Laboratory of Organic Materials Testing Technology & Quality Evaluation, Beijing, 100089, China
| | - Tiantian Yang
- Beijing National Laboratory for Molecular Sciences, CAS Key Laboratory of Engineering Plastics, Institute of Chemistry, Chinese Academy of Sciences (CAS), Beijing, 100190, China; University of Chinese Academy of Sciences, Beijing, 100049, China
| | - Xiaocheng Zhang
- Beijing National Laboratory for Molecular Sciences, CAS Key Laboratory of Engineering Plastics, Institute of Chemistry, Chinese Academy of Sciences (CAS), Beijing, 100190, China
| | - Jun Zhang
- Beijing National Laboratory for Molecular Sciences, CAS Key Laboratory of Engineering Plastics, Institute of Chemistry, Chinese Academy of Sciences (CAS), Beijing, 100190, China; University of Chinese Academy of Sciences, Beijing, 100049, China.
| |
Collapse
|
8
|
Abstract
Stereospecific recognition of chiral molecules plays an important role in nature as the basis of the interaction of chiral bioactive compounds with the chiral target structures. In separation sciences such as chromatographic and capillary electromigration techniques, interactions between chiral analytes and chiral selectors, i.e., the formation of transient diastereomeric complexes in thermodynamic equilibria, are the basis for chiral separations. Due to the large structural variety of chiral selectors, different structural features contribute to the overall chiral recognition process. This introductory chapter briefly summarizes the present understanding of the structural enantioselective recognition processes for various types of chiral selectors.
Collapse
Affiliation(s)
- Gerhard K E Scriba
- Department of Pharmaceutical Chemistry, University of Jena, Jena, Germany.
| |
Collapse
|
9
|
Cecilio Fonseca M, Santos da Silva RC, Nascimento CS, Bastos Borges K. Computational contribution to the electrophoretic enantiomer separation mechanism and migration order using modified β-cyclodextrins. Electrophoresis 2017; 38:1860-1868. [PMID: 28387965 DOI: 10.1002/elps.201600468] [Citation(s) in RCA: 22] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/11/2016] [Revised: 03/22/2017] [Accepted: 03/25/2017] [Indexed: 11/07/2022]
Abstract
Capillary electrophoresis (CE) is an extremely effective technique in many kinds of separations, including separation of enantiomers. Some additional techniques may be necessary to determine the enantiomer migration order (EMO) and also the mechanism involved in chiral recognition. This paper reports the development and optimization of a CE method for enantioseparation of racemic mixture of both R- and S-stereoisomers of tramadol (TRM) with a computational contribution for the EMO determination and the responsible mechanisms for chiral distinction. Parameters such as composition and concentration of background electrolyte (BGE) and type and concentration of cyclodextrins (CD) were evaluated. For calculations, a sequential methodology was used, resorting to semiempirical Parametric Model 3 (PM3) followed by calculations accomplished using density functional theory. The best results were obtained with sulfated-β-CD (s-β-CD) and carboxymethyl-β-cyclodextrin (cm-β-CD) as chiral selector. Calculations show that the inclusion of TRM is not a probable process due to the shape of the TRM molecule and the size CDs cavities. Therefore, the chiral recognition process occurs by the formation of association complexes between modified β-CD and groups of TRM molecules. The structural analysis of the fragments of complexes at a pH of 10 and a thermodynamic analysis of the complexes' formation process allows determining the EMO. Comparing results obtained experimentally and computationally, it seems that the developed method is adequate for separation of TRM enantiomers and the computational methodology is also adequate to get a sense of the system at a molecular level.
Collapse
Affiliation(s)
- Matheus Cecilio Fonseca
- Departamento de Ciências Naturais, Universidade Federal de São João del-Rei, São João del-Rei, Minas Gerais, Brazil
| | - Ricky Cássio Santos da Silva
- Departamento de Ciências Naturais, Universidade Federal de São João del-Rei, São João del-Rei, Minas Gerais, Brazil
| | - Clebio Soares Nascimento
- Departamento de Ciências Naturais, Universidade Federal de São João del-Rei, São João del-Rei, Minas Gerais, Brazil
| | - Keyller Bastos Borges
- Departamento de Ciências Naturais, Universidade Federal de São João del-Rei, São João del-Rei, Minas Gerais, Brazil
| |
Collapse
|
10
|
Abstract
Stereospecific recognition of chiral molecules is an important issue in various aspects of life sciences and chemistry including analytical separation sciences. The basis of analytical enantioseparations is the formation of transient diastereomeric complexes driven by hydrogen bonds or ionic, ion-dipole, dipole-dipole, van der Waals as well as π-π interactions. Recently, halogen bonding was also described to contribute to selector-selectand complexation. Besides structure-separation relationships, spectroscopic techniques, especially NMR spectroscopy, as well as X-ray crystallography have contributed to the understanding of the structure of the diastereomeric complexes. Molecular modeling has provided the tool for the visualization of the structures. The present review highlights recent contributions to the understanding of the binding mechanism between chiral selectors and selectands in analytical enantioseparations dating between 2012 and early 2016 including polysaccharide derivatives, cyclodextrins, cyclofructans, macrocyclic glycopeptides, proteins, brush-type selectors, ion-exchangers, polymers, crown ethers, ligand-exchangers, molecular micelles, ionic liquids, metal-organic frameworks and nucleotide-derived selectors. A systematic compilation of all published literature on the various chiral selectors has not been attempted.
Collapse
Affiliation(s)
- Gerhard K E Scriba
- Friedrich Schiller University Jena, Department of Pharmaceutical/Medicinal Chemistry, Philosophenweg 14, 07743 Jena, Germany.
| |
Collapse
|
11
|
Zhang Q, Shi H, Gao B, Tian M, Hua X, Wang M. Enantioseparation and determination of the chiral phenylpyrazole insecticide ethiprole in agricultural and environmental samples and its enantioselective degradation in soil. Sci Total Environ 2016; 542:845-853. [PMID: 26556749 DOI: 10.1016/j.scitotenv.2015.10.132] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/25/2015] [Revised: 10/26/2015] [Accepted: 10/26/2015] [Indexed: 06/05/2023]
Abstract
An effective method for the enantioselective determination of ethiprole enantiomers in agricultural and environmental samples was developed. The effects of solvent extraction, mobile phase and thermodynamic parameters for chiral recognition were fully investigated. Complete enantioseparation of the ethiprole enantiomers was achieved on a Lux Cellulose-2 column. The stereochemical structures of ethiprole enantiomers were also determined, and (R)-(+)-ethiprole was first eluted. The average recoveries were 82.7-104.9% with intra-day RSD of 1.7-8.2% in soil, cucumber, spinach, tomato, apple and peach under optimal conditions. Good linearity (R(2)≥0.9991) was obtained for all the matrix calibration curves within a range of 0.1 to 10 mg L(-1). The limits of detection for both enantiomers were estimated to be 0.008 mg kg(-1) in soil, cucumber, spinach and tomato and 0.012 mg kg(-1) in apple and peach, which were lower than the maximum residue levels established in Japan. The results indicate that the proposed method is convenient and reliable for the enantioselective detection of ethiprole in agricultural and environmental samples. The behavior of ethiprole in soil was studied under field conditions and the enantioselective degradation was observed with enantiomer fraction values varying from 0.494 to 0.884 during the experiment. The (R)-(+)-ethiprole (t1/2=11.6 d) degraded faster than (S)-(-)-ethiprole (t1/2=34.7 d). This report is the first describe a chiral analytical method and enantioselective behavior of ethiprole, and these results should be extremely useful for the risk evaluation of ethiprole in food and environmental safety.
Collapse
Affiliation(s)
- Qing Zhang
- Department of Pesticide Science, College of Plant Protection, Nanjing Agricultural University, State & Local Joint Engineering Research Center of Green Pesticide Invention and Application, Key Laboratory of Integrated Management of Crop Diseases and Pests, Ministry of Education, Nanjing 210095, PR China
| | - Haiyan Shi
- Department of Pesticide Science, College of Plant Protection, Nanjing Agricultural University, State & Local Joint Engineering Research Center of Green Pesticide Invention and Application, Key Laboratory of Integrated Management of Crop Diseases and Pests, Ministry of Education, Nanjing 210095, PR China
| | - Beibei Gao
- Department of Pesticide Science, College of Plant Protection, Nanjing Agricultural University, State & Local Joint Engineering Research Center of Green Pesticide Invention and Application, Key Laboratory of Integrated Management of Crop Diseases and Pests, Ministry of Education, Nanjing 210095, PR China
| | - Mingming Tian
- Department of Pesticide Science, College of Plant Protection, Nanjing Agricultural University, State & Local Joint Engineering Research Center of Green Pesticide Invention and Application, Key Laboratory of Integrated Management of Crop Diseases and Pests, Ministry of Education, Nanjing 210095, PR China
| | - Xiude Hua
- Department of Pesticide Science, College of Plant Protection, Nanjing Agricultural University, State & Local Joint Engineering Research Center of Green Pesticide Invention and Application, Key Laboratory of Integrated Management of Crop Diseases and Pests, Ministry of Education, Nanjing 210095, PR China
| | - Minghua Wang
- Department of Pesticide Science, College of Plant Protection, Nanjing Agricultural University, State & Local Joint Engineering Research Center of Green Pesticide Invention and Application, Key Laboratory of Integrated Management of Crop Diseases and Pests, Ministry of Education, Nanjing 210095, PR China.
| |
Collapse
|
12
|
Wang D, Li F, Jiang Z, Yu L, Guo X. Chiral Recognition Mechanisms of four β-Blockers by HPLC with Amylose Chiral Stationary Phase. Iran J Pharm Res 2014; 13:449-57. [PMID: 25237340 PMCID: PMC4157020] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
Abstract
The high performance liquid chromatography (HPLC) enantioseparation of four β-blocking agents metoprolol, bisoprolol, propranolol and atenolol was performed on amylose tris-(3,5-dimethylphenylcarbamate) chiral stationary phase using n-hexane-ethanol-diethylamine (DEA) as the mobile phase and related chiral recognition mechanisms were discussed. Enantiomeric separation of the four β-blockers was a result of more than one type of interaction between solutes and CSP. Besides hydrogen bonding, there was another type interaction that was independent of solvent polarity and responsible for enantiomeric selectivity, such as - interactions. Both the groups close to the chiral centers and the substituent groups on the phenyl rings, which were far away from the chiral centers, could contribute to the good separation. The separations of the four β-blocker enantiomers were all enthalpy driven process. In the range of 293-308K (20-35 ℃), as the temperature increased, the retention as well as the resolution decreased. The molecular size rather than concentration of the alcohol modifiers affected the resolution and retention.
Collapse
|