1
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Dobšíková K, Kohout M, Setnička V. Chiral separation and spectroscopic characterization of mefloquine analogues. SPECTROCHIMICA ACTA. PART A, MOLECULAR AND BIOMOLECULAR SPECTROSCOPY 2024; 324:124940. [PMID: 39173319 DOI: 10.1016/j.saa.2024.124940] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/28/2024] [Revised: 06/25/2024] [Accepted: 08/05/2024] [Indexed: 08/24/2024]
Abstract
Mefloquine, a widely used antimalarial agent, has spurred ongoing research into the development of derivatives with enhanced efficacy and reduced side effects. In this investigation, we synthesized two compounds containing N-allyl or N-tert-butylacetamid groups. A chiral liquid chromatography with polysaccharide chiral stationary phase was utilized to separate the enantiomers of both derivatives. We employed spectroscopic chiroptical and non-polarizable methods such as electronic and vibrational circular dichroism, infrared absorption and ultraviolet spectroscopies. Combined with density functional theory calculations, the stable conformers were found in solution and their spectra were subsequently simulated. We elucidated the three-dimensional structure of the enantiomerically pure compounds and assigned the absolute configuration of all prepared derivatives using both experimental and simulated spectra.
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Affiliation(s)
- K Dobšíková
- Department of Analytical Chemistry, University of Chemistry and Technology, Technická 5, Prague 6 166 28, Czech Republic
| | - M Kohout
- Department of Organic Chemistry, University of Chemistry and Technology, Technická 5, Prague 6 166 28, Czech Republic
| | - V Setnička
- Department of Analytical Chemistry, University of Chemistry and Technology, Technická 5, Prague 6 166 28, Czech Republic.
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2
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Borré LB, Sousa EGR, San Gil RAS, Baptista MM, Leitão AA, De Almeida JMAR, Carr O, Oliveira ON, Shimizu FM, Guimarães TF. Solid-State NMR Characterization of Mefloquine Resinate Complexes Designed for Taste-Masking Pediatric Formulations. Pharmaceuticals (Basel) 2024; 17:870. [PMID: 39065722 PMCID: PMC11280060 DOI: 10.3390/ph17070870] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/30/2024] [Revised: 06/12/2024] [Accepted: 06/19/2024] [Indexed: 07/28/2024] Open
Abstract
Mefloquine (MQ) is an antimalarial medication prescribed to treat or malaria prevention.. When taken by children, vomiting usually occurs, and new doses of medication frequently need to be taken. So, developing pediatric medicines using taste-masked antimalarial drug complexes is mandatory for the success of mefloquine administration. The hypothesis that binding mefloquine to an ion-exchange resin (R) could circumvent the drug's bitter taste problem was proposed, and solid-state 13C cross-polarization magic angle spinning (CPMAS) NMR was able to follow MQ-R mixtures through chemical shift and relaxation measurements. The nature of MQ-R complex formation could then be determined. Impedimetric electronic tongue equipment also verified the resinate taste-masking efficiency in vitro. Variations in chemical shifts and structure dynamics measured by proton relaxation properties (e.g., T1ρH) were used as probes to follow the extension of mixing and specific interactions that would be present in MQ-R. A significant decrease in T1ρH values was observed for MQ carbons in MQ-R complexes, compared to the ones in MQ (from 100-200 ms in MQ to 20-50 ms in an MQ-R complex). The results evidenced that the cationic resin interacts strongly with mefloquine molecules in the formulation of a 1:1 ratio complex. Thus, 13C CPMAS NMR allowed the confirmation of the presence of a binding between mefloquine and polacrilin in the MQ-R formulation studied.
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Affiliation(s)
- Leandro B. Borré
- Instituto de Química, Universidade Federal do Rio de Janeiro, Rio de Janeiro 21941-909, RJ, Brazil; (L.B.B.); (M.M.B.); (J.M.A.R.D.A.)
| | - Eduardo G. R. Sousa
- Instituto de Tecnologia em Fármacos (Farmanguinhos), Fundação Oswaldo Cruz, Rio de Janeiro 21041-250, RJ, Brazil; (E.G.R.S.); (T.F.G.)
| | - Rosane A. S. San Gil
- Instituto de Química, Universidade Federal do Rio de Janeiro, Rio de Janeiro 21941-909, RJ, Brazil; (L.B.B.); (M.M.B.); (J.M.A.R.D.A.)
- Instituto de Pesquisa de Produtos Naturais, Universidade Federal do Rio de Janeiro, CCS, Rio de Janeiro 21941-599, RJ, Brazil
| | - Mateus M. Baptista
- Instituto de Química, Universidade Federal do Rio de Janeiro, Rio de Janeiro 21941-909, RJ, Brazil; (L.B.B.); (M.M.B.); (J.M.A.R.D.A.)
| | - Alexandre A. Leitão
- Departamento de Química, Universidade Federal de Juiz de Fora, Juiz de Fora 36036-900, MG, Brazil;
| | - João M. A. R. De Almeida
- Instituto de Química, Universidade Federal do Rio de Janeiro, Rio de Janeiro 21941-909, RJ, Brazil; (L.B.B.); (M.M.B.); (J.M.A.R.D.A.)
| | - Olívia Carr
- São Carlos Institute of Physics, University of São Paulo, São Carlos 13566-590, SP, Brazil; (O.C.); (O.N.O.J.)
| | - Osvaldo N. Oliveira
- São Carlos Institute of Physics, University of São Paulo, São Carlos 13566-590, SP, Brazil; (O.C.); (O.N.O.J.)
| | - Flávio M. Shimizu
- Department of Applied Physics, Institute of Physics (IFGW), University of Campinas (UNICAMP), “Gleb Wataghin”, Campinas 13083-970, SP, Brazil;
| | - Thiago F. Guimarães
- Instituto de Tecnologia em Fármacos (Farmanguinhos), Fundação Oswaldo Cruz, Rio de Janeiro 21041-250, RJ, Brazil; (E.G.R.S.); (T.F.G.)
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3
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Guin S, Alden KM, Krysan DJ, Meyers MJ. Synthesis and Antifungal Activity of Stereoisomers of Mefloquine Analogs. ACS Med Chem Lett 2024; 15:822-827. [PMID: 38894917 PMCID: PMC11181485 DOI: 10.1021/acsmedchemlett.4c00031] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/18/2024] [Revised: 04/23/2024] [Accepted: 04/26/2024] [Indexed: 06/21/2024] Open
Abstract
Cryptococcal neoformans and Candida albicans are among the most prevalent causes of life-threatening fungal infections globally. The high mortality associated with these infections despite current antifungal therapy highlights the need for new drugs. In our previous work, we demonstrated that an analogue of the clinically used antimalarial mefloquine, (8-chloro-2-(4-chlorophenyl)quinolin-4-yl)(piperidin-2-yl)methanol (4377), has both antifungal activity and the ability to penetrate the central nervous system. Herein we describe the synthesis and antifungal assay of all four stereoisomers of 4377. All four stereoisomers retain potent antifungal activity with the erythro enantiomers having MIC values of 1 and 4 μg/mL against C. neoformans and C. albicans, respectively, and threo enantiomers, MIC values of 2 and 8 μg/mL, respectively. These results indicate that the stereochemistry of the piperidine methanol group is not critical for the antifungal properties of 4377 and gives guidance to future medicinal chemistry optimization efforts.
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Affiliation(s)
- Soumitra Guin
- Department
of Chemistry, School of Science and Engineering, Saint Louis University, Saint
Louis, Missouri 63103, United States
| | - Kathryn M. Alden
- Department
of Pediatrics, Carver College of Medicine, University of Iowa, Iowa City, Iowa 52242, United States
- Department
of Molecular Physiology and Biophysics, University of Iowa, Iowa City, Iowa 52242, United States
| | - Damian J. Krysan
- Department
of Pediatrics, Carver College of Medicine, University of Iowa, Iowa City, Iowa 52242, United States
- Department
of Molecular Physiology and Biophysics, University of Iowa, Iowa City, Iowa 52242, United States
| | - Marvin J. Meyers
- Department
of Chemistry, School of Science and Engineering, Saint Louis University, Saint
Louis, Missouri 63103, United States
- Institute
for Drug and Biotherapeutic Innovation, Saint Louis University, St. Louis, Missouri 63103, United States
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4
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Fuentes-Monteverde JCC, Nath N, Forero AM, Balboa EM, Navarro-Vázquez A, Griesinger C, Jiménez C, Rodríguez J. Connection of Isolated Stereoclusters by Combining 13C-RCSA, RDC, and J-Based Configurational Analyses and Structural Revision of a Tetraprenyltoluquinol Chromane Meroterpenoid from Sargassum muticum. Mar Drugs 2022; 20:462. [PMID: 35877755 PMCID: PMC9319238 DOI: 10.3390/md20070462] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/21/2022] [Revised: 07/06/2022] [Accepted: 07/15/2022] [Indexed: 12/10/2022] Open
Abstract
The seaweed Sargassum muticum, collected on the southern coast of Galicia, yielded a tetraprenyltoluquinol chromane meroditerpene compound known as 1b, whose structure is revised. The relative configuration of 1b was determined by J-based configurational methodology combined with an iJ/DP4 statistical analysis and further confirmed by measuring two anisotropic properties: carbon residual chemical shift anisotropies (13C-RCSAs) and one-bond 1H-13C residual dipolar couplings (1DCH-RDCs). The absolute configuration of 1b was deduced by ECD/OR/TD-DFT methods and established as 3R,7S,11R.
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Affiliation(s)
- Juan Carlos C. Fuentes-Monteverde
- Departamento de Química e Centro de Investigacións Científicas Avanzadas (CICA), Universidade da Coruña, 15071 A Coruña, Spain; (J.C.C.F.-M.); (A.M.F.)
- NMR Based Structural Biology, MPI for Multidisciplinary Sciences, Am Fassberg 11, 37077 Göttingen, Germany
| | - Nilamoni Nath
- Department of Chemistry, Gauhati University, Gopinath Bardoloi Nagar, Guwahati 781014, India;
| | - Abel M. Forero
- Departamento de Química e Centro de Investigacións Científicas Avanzadas (CICA), Universidade da Coruña, 15071 A Coruña, Spain; (J.C.C.F.-M.); (A.M.F.)
| | - Elena M. Balboa
- Department of Chemical Engineering, Faculty of Science, Campus Ourense, University of Vigo, As Lagoas s/n, 32004 Ourense, Spain;
| | - Armando Navarro-Vázquez
- Departamento de Química Fundamental, CCEN, Universidade Federal de Pernambuco, Cidade Universitária, Recife 50740-550, Brazil;
| | - Christian Griesinger
- NMR Based Structural Biology, MPI for Multidisciplinary Sciences, Am Fassberg 11, 37077 Göttingen, Germany
| | - Carlos Jiménez
- Departamento de Química e Centro de Investigacións Científicas Avanzadas (CICA), Universidade da Coruña, 15071 A Coruña, Spain; (J.C.C.F.-M.); (A.M.F.)
| | - Jaime Rodríguez
- Departamento de Química e Centro de Investigacións Científicas Avanzadas (CICA), Universidade da Coruña, 15071 A Coruña, Spain; (J.C.C.F.-M.); (A.M.F.)
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Kucharski D, Kowalczyk R, Boratyński PJ. Chiral Vicinal Diamines Derived from Mefloquine. J Org Chem 2021; 86:10654-10664. [PMID: 34314190 PMCID: PMC8389910 DOI: 10.1021/acs.joc.1c01316] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/05/2021] [Indexed: 11/30/2022]
Abstract
Novel 1,2-diamines based on the mefloquine scaffold prepared in enantiomerically pure forms resemble 9-amino-Cinchona alkaloids. Most effectively, 11-aminomefloquine with an erythro configuration was obtained by conversion of 11-alcohol into azide and hydrogenation. Alkylation of a secondary amine unit was needed to arrive at diastereomeric threo-11-aminomefloquine and to introduce diversity. Most of the substitution reactions of the hydroxyl group to azido group proceeded with net retention of the configuration and involved actual aziridine or plausible aziridinium ion intermediates. Enantiomerically pure products were obtained by the resolution of either the initial mefloquine or one of the final products. The evaluation of the efficacy of the obtained vicinal diamines in enantioselective transformations proved that erythro-11-aminomefloquine is an effective catalyst in the asymmetric Michael addition of nitromethane to cyclohexanone (up to 96.5:3.5 er) surpassing epi-aminoquinine in terms of selectivity.
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Affiliation(s)
- Dawid
J. Kucharski
- Department
of Organic and Medicinal Chemistry, Wrocław
University of Technology, Wyb. Wyspiańskiego 26, Wrocław 50370 Poland
| | - Rafał Kowalczyk
- Department
of Bioorganic chemistry, Wrocław University
of Technology, Wyb. Wyspiańskiego 26, Wrocław 50370 Poland
| | - Przemysław J. Boratyński
- Department
of Organic and Medicinal Chemistry, Wrocław
University of Technology, Wyb. Wyspiańskiego 26, Wrocław 50370 Poland
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6
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Das A, Nath N. Elucidating natural product structures using a robust measurement of carbon residual chemical shift anisotropy combined with DFT. MAGNETIC RESONANCE IN CHEMISTRY : MRC 2021; 59:569-576. [PMID: 31758720 DOI: 10.1002/mrc.4975] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/17/2019] [Revised: 08/20/2019] [Accepted: 08/31/2019] [Indexed: 06/10/2023]
Abstract
Determination of configurations and conformations is an important step in the structural characterization of small molecules. Apart from utilizing isotropic J-couplings and nuclear overhauser effect (NOEs) measured in isotropic solution, anisotropic Nuclear Magnetic resonance (NMR) data such as residual dipolar couplings and residual chemical shift anisotropies (RCSAs) were also used to elucidate complex small molecule structures. Measuring RCSA has always been historically difficult due to the isotropic shift effect accompanied by molecular alignment and therefore only occasionally applied in a few examples. Here, we present a robust measurement of carbon RCSAs using a smaller gel-stretching device to determine the structures of a few small molecules. A systematic study on how different density functional theory computed anisotropies of the chemical shift anisotropy tensors impact RCSA data interpretation has also been discussed. We also discuss the effect of utilizing various carbons as reference nuclei for RCSA data extraction as well as the orientation behavior of estrone in orthogonal alignment media.
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Affiliation(s)
- Akhi Das
- Department of Chemistry, Gauhati University, Guwahati, India
| | - Nilamoni Nath
- Department of Chemistry, Gauhati University, Guwahati, India
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7
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Relative configuration of micrograms of natural compounds using proton residual chemical shift anisotropy. Nat Commun 2020; 11:4372. [PMID: 32873801 PMCID: PMC7463026 DOI: 10.1038/s41467-020-18093-5] [Citation(s) in RCA: 20] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/23/2019] [Accepted: 07/28/2020] [Indexed: 01/12/2023] Open
Abstract
3D molecular structure determination is a challenge for organic compounds or natural products available in minute amounts. Proton/proton and proton/carbon correlations yield the constitution. J couplings and NOEs oftentimes supported by one-bond 1H,13C residual dipolar couplings (RDCs) or by 13C residual chemical shift anisotropies (RCSAs) provide the relative configuration. However, these RDCs or carbon RCSAs rely on 1% natural abundance of 13C preventing their use for compounds available only in quantities of a few 10’s of µgs. By contrast, 1H RCSAs provide similar information on spatial orientation of structural moieties within a molecule, while using the abundant 1H spin. Herein, 1H RCSAs are accurately measured using constrained aligning gels or liquid crystals and applied to the 3D structural determination of molecules with varying complexities. Even more, deuterated alignment media allow the elucidation of the relative configuration of around 35 µg of a briarane compound isolated from Briareum asbestinum. Determination of 3D molecular structures remains challenging for natural products or organic compounds available in minute amounts. Here, the authors determine the structure of complex molecules, including few micrograms of briarane B-3 isolated from Briareum asbestinums, through measurement of 1H residual chemical shift anisotropy.
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8
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Yang GZ, Zhu JK, Yin XD, Yan YF, Wang YL, Shang XF, Liu YQ, Zhao ZM, Peng JW, Liu H. Design, Synthesis, and Antifungal Evaluation of Novel Quinoline Derivatives Inspired from Natural Quinine Alkaloids. JOURNAL OF AGRICULTURAL AND FOOD CHEMISTRY 2019; 67:11340-11353. [PMID: 31532201 DOI: 10.1021/acs.jafc.9b04224] [Citation(s) in RCA: 46] [Impact Index Per Article: 9.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/10/2023]
Abstract
Inspired by quinine and its analogues, we designed, synthesized, and evaluated two series of quinoline small molecular compounds (a and 2a) and six series of quinoline derivatives (3a-f) for their antifungal activities. The results showed that compounds 3e and 3f series exhibited significant fungicidal activities. Significantly, compounds 3f-4 (EC50 = 0.41 μg/mL) and 3f-28 (EC50 = 0.55 μg/mL) displayed the superior in vitro fungicidal activity and the potent in vivo curative effect against Sclerotinia sclerotiorum. Preliminary mechanism studies showed that compounds 3f-4 and 3f-28 could cause changes in the cell membrane permeability, accumulation of reactive oxygen species, loss of mitochondrial membrane potential, and effective inhibition of germination and formation of S. sclerotiorum sclerotia. These results indicate that compounds 3f-4 and 3f-28 are novel potential fungicidal candidates against S. sclerotiorum derived from natural products.
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Affiliation(s)
- Guan-Zhou Yang
- School of Pharmacy , Lanzhou University , Lanzhou 730000 , People's Republic of China
| | - Jia-Kai Zhu
- School of Pharmacy , Lanzhou University , Lanzhou 730000 , People's Republic of China
| | - Xiao-Dan Yin
- School of Pharmacy , Lanzhou University , Lanzhou 730000 , People's Republic of China
| | - Yin-Fang Yan
- School of Pharmacy , Lanzhou University , Lanzhou 730000 , People's Republic of China
| | - Yu-Ling Wang
- Gansu Academy of Agricultural Sciences , Lanzhou 730000 , People's Republic of China
| | - Xiao-Fei Shang
- School of Pharmacy , Lanzhou University , Lanzhou 730000 , People's Republic of China
| | - Ying-Qian Liu
- School of Pharmacy , Lanzhou University , Lanzhou 730000 , People's Republic of China
| | - Zhong-Min Zhao
- School of Pharmacy , Lanzhou University , Lanzhou 730000 , People's Republic of China
| | - Jing-Wen Peng
- School of Pharmacy , Lanzhou University , Lanzhou 730000 , People's Republic of China
| | - Hua Liu
- School of Pharmacy , Lanzhou University , Lanzhou 730000 , People's Republic of China
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9
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Lu Y, Qin S, Zhang B, Dai A, Cai X, Ma M, Gao ZG, Yang D, Stevens RC, Jacobson KA, Wang MW, Shui W. Accelerating the Throughput of Affinity Mass Spectrometry-Based Ligand Screening toward a G Protein-Coupled Receptor. Anal Chem 2019; 91:8162-8169. [PMID: 31094506 PMCID: PMC6669887 DOI: 10.1021/acs.analchem.9b00477] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/02/2023]
Abstract
Affinity mass spectrometry (MS) enables rapid screening of compound mixtures for ligands bound to a specific protein target, yet its current throughput is limited to individually assay pools of 400-2000 compounds. Typical affinity MS screens implemented in pharmaceutical industry laboratories identify putative ligands based on qualitative analysis of compound binding to the target whereas no quantitative information is acquired to discriminate high- and low-affinity ligands in the screening phase. Furthermore, these screens require purification of a stabilized form of the protein target, which poses a great challenge for membrane receptor targets. Here, we describe a new, potentially general affinity MS strategy that allows screening of 20,000 compounds in one pool for highly efficient ligand discovery toward a G protein-coupled receptor (GPCR) target. Quantitative measurement of compound binding to the receptor enables high-affinity ligand selection using both the purified receptor and receptor-embedded cell membranes. This high-throughput, label-free and quantitative affinity MS screen resulted in discovery of three new antagonists of the A2A adenosine receptor.
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Affiliation(s)
- Yan Lu
- iHuman Institute, ShanghaiTech University, 201210 Shanghai, China
- School of Life Science and Technology, ShanghaiTech University, 201210 Shanghai, China
- University of Chinese Academy of Sciences, 100049 Beijing, China
| | - Shanshan Qin
- iHuman Institute, ShanghaiTech University, 201210 Shanghai, China
| | - Bingjie Zhang
- iHuman Institute, ShanghaiTech University, 201210 Shanghai, China
| | - Antao Dai
- The National Center for Drug Screening and the CAS Key Laboratory of Receptor Research, Shanghai Institute of Materia Medica, Chinese Academy of Sciences, 201203 Shanghai, China
| | - Xiaoqing Cai
- The National Center for Drug Screening and the CAS Key Laboratory of Receptor Research, Shanghai Institute of Materia Medica, Chinese Academy of Sciences, 201203 Shanghai, China
| | - Mengna Ma
- iHuman Institute, ShanghaiTech University, 201210 Shanghai, China
- School of Life Science and Technology, ShanghaiTech University, 201210 Shanghai, China
- University of Chinese Academy of Sciences, 100049 Beijing, China
| | - Zhan-Guo Gao
- National Institute of Diabetes and Digestive and Kidney Diseases (NIDDK), National Institutes of Health, Bethesda, Maryland 20892 United States
| | - Dehua Yang
- The National Center for Drug Screening and the CAS Key Laboratory of Receptor Research, Shanghai Institute of Materia Medica, Chinese Academy of Sciences, 201203 Shanghai, China
| | - Raymond C. Stevens
- iHuman Institute, ShanghaiTech University, 201210 Shanghai, China
- School of Life Science and Technology, ShanghaiTech University, 201210 Shanghai, China
| | - Kenneth A. Jacobson
- National Institute of Diabetes and Digestive and Kidney Diseases (NIDDK), National Institutes of Health, Bethesda, Maryland 20892 United States
| | - Ming-Wei Wang
- University of Chinese Academy of Sciences, 100049 Beijing, China
- The National Center for Drug Screening and the CAS Key Laboratory of Receptor Research, Shanghai Institute of Materia Medica, Chinese Academy of Sciences, 201203 Shanghai, China
- School of Pharmacy, Fudan University, 201203 Shanghai, China
| | - Wenqing Shui
- iHuman Institute, ShanghaiTech University, 201210 Shanghai, China
- School of Life Science and Technology, ShanghaiTech University, 201210 Shanghai, China
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10
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Engwerda AHJ, Maassen R, Tinnemans P, Meekes H, Rutjes FPJT, Vlieg E. Attrition-Enhanced Deracemization of the Antimalaria Drug Mefloquine. Angew Chem Int Ed Engl 2018; 58:1670-1673. [PMID: 30508314 DOI: 10.1002/anie.201811289] [Citation(s) in RCA: 20] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/01/2018] [Indexed: 11/10/2022]
Abstract
Mefloquine is an important drug for prevention and treatment of malaria. It is commercially available as a racemic mixture, wherein only one enantiomer is active against malaria, while the other one causes severe psychotropic effects. By converting the drug into a compound that crystallizes as a racemizable racemic conglomerate, the deracemization of mefloquine into the desired enantiomer was achieved.
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Affiliation(s)
- Anthonius H J Engwerda
- Institute for Molecules and Materials, Radboud University, Heyendaalseweg 135, 6525, AJ, Nijmegen, The Netherlands
| | - Rick Maassen
- Institute for Molecules and Materials, Radboud University, Heyendaalseweg 135, 6525, AJ, Nijmegen, The Netherlands
| | - Paul Tinnemans
- Institute for Molecules and Materials, Radboud University, Heyendaalseweg 135, 6525, AJ, Nijmegen, The Netherlands
| | - Hugo Meekes
- Institute for Molecules and Materials, Radboud University, Heyendaalseweg 135, 6525, AJ, Nijmegen, The Netherlands
| | - Floris P J T Rutjes
- Institute for Molecules and Materials, Radboud University, Heyendaalseweg 135, 6525, AJ, Nijmegen, The Netherlands
| | - Elias Vlieg
- Institute for Molecules and Materials, Radboud University, Heyendaalseweg 135, 6525, AJ, Nijmegen, The Netherlands
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11
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12
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Application of anisotropic NMR parameters to the confirmation of molecular structure. Nat Protoc 2018; 14:217-247. [DOI: 10.1038/s41596-018-0091-9] [Citation(s) in RCA: 65] [Impact Index Per Article: 10.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
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13
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Kumari A, Karnatak M, Singh D, Shankar R, Jat JL, Sharma S, Yadav D, Shrivastava R, Verma VP. Current scenario of artemisinin and its analogues for antimalarial activity. Eur J Med Chem 2018; 163:804-829. [PMID: 30579122 DOI: 10.1016/j.ejmech.2018.12.007] [Citation(s) in RCA: 53] [Impact Index Per Article: 8.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/12/2018] [Revised: 11/29/2018] [Accepted: 12/02/2018] [Indexed: 11/17/2022]
Abstract
Human malaria, one of the most striking, reemerging infectious diseases, is caused by several types of Plasmodium parasites. Whilst advances have been made in lowering the numbers of cases and deaths, it is clear that a strategy based solely on disease control year on year, without reducing transmission and ultimately eradicating the parasite, is unsustainable. Natural products have served as a template for the design and development of antimalarial drugs currently in the clinic or in the development phase. Artemisinin combine potent, rapid antimalarial activity with a wide therapeutic index and an absence of clinically important resistance. The alkylating ability of artemisinin and its semi-synthetic analogues toward heme related to their antimalarial efficacy are underlined. Although impressive results have already been achieved in malaria research, more systematization and concentration of efforts are required if real breakthroughs are to be made. This review will concisely cover the clinical, preclinical antimalarial and current updates in artemisinin based antimalarial drugs. Diverse classes of semi-synthetic analogs of artemisinin reported in the last decade have also been extensively studied. The experience gained in this respect is discussed.
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Affiliation(s)
- Akriti Kumari
- Department of Chemistry, Banasthali University, Banasthali Newai, 304022, Rajasthan, India
| | - Manvika Karnatak
- Department of Chemistry, Banasthali University, Banasthali Newai, 304022, Rajasthan, India
| | - Davinder Singh
- Bio-Organic Chemistry Division, CSIR-Indian Institute of Integrative Medicine, Jammu, 180001, Jammu and Kashmir, India
| | - Ravi Shankar
- Bio-Organic Chemistry Division, CSIR-Indian Institute of Integrative Medicine, Jammu, 180001, Jammu and Kashmir, India
| | - Jawahar L Jat
- Department of Applied Chemistry, BabaSaheb Bhimrao Ambedkar University (A Central University), Vidya Vihar Raebareli Road, Lucknow, 226025, India
| | - Siddharth Sharma
- Department of Chemistry, Mohanlal Sukhadia University, Udaipur, 313001, India
| | - Dinesh Yadav
- Department of Chemistry, Mohanlal Sukhadia University, Udaipur, 313001, India
| | - Rahul Shrivastava
- Department of Chemistry, Manipal University Jaipur, Jaipur, 303007, India
| | - Ved Prakash Verma
- Department of Chemistry, Banasthali University, Banasthali Newai, 304022, Rajasthan, India.
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14
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Inthajak K, Toochinda P, Lawtrakul L. Application of molecular docking and PSO-SVR intelligent approaches in antimalarial activity prediction of enantiomeric cycloguanil analogues. SAR AND QSAR IN ENVIRONMENTAL RESEARCH 2018; 29:957-974. [PMID: 30381963 DOI: 10.1080/1062936x.2018.1536678] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/13/2018] [Accepted: 10/12/2018] [Indexed: 06/08/2023]
Abstract
A series of antifolate compounds, i.e. 1-(4-chlorophenyl)-6,6-dimethyl-1,3,5-triazine-2,4-diamine, or cycloguanil analogues, have shown effective inhibiting properties against Plasmodium falciparum dihydrofolate reductase (PfDHFR). In this work, the stereoselectivity of PfDHFR to the R and S enantiomer of cycloguanil analogues was obtained from molecular docking calculations and integrated into QSAR study to obtain a more accurate prediction model. Results indicate that PfDHFR can bind to cycloguanil analogues in the R and S enantiomers. Cycloguanil analogues with alkyl chain substituent prefer the R enantiomer over S because they do not experience steric hindrance with the Phe58 side chain, while cycloguanil analogues with phenol chain substituent prefer the S enantiomer over R because they do not experience steric hindrance with Leu46 and Met55 side chains. Particle swarm optimization and support vector regression were used to select relevant descriptors and generate the effective prediction model, with a high statistical significance level (r2training = 0.941; r2test = 0.884).
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Affiliation(s)
- K Inthajak
- a School of Bio-Chemical Engineering and Technology , Sirindhorn International Institute of Technology, Thammasat University , Pathum Thani , Thailand
| | - P Toochinda
- a School of Bio-Chemical Engineering and Technology , Sirindhorn International Institute of Technology, Thammasat University , Pathum Thani , Thailand
| | - L Lawtrakul
- a School of Bio-Chemical Engineering and Technology , Sirindhorn International Institute of Technology, Thammasat University , Pathum Thani , Thailand
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15
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Chen D, Sun X, Shan Y, You J. One-pot synthesis of polyfunctionalized quinolines via a copper-catalyzed tandem cyclization. Org Biomol Chem 2018; 16:7657-7662. [PMID: 30283970 DOI: 10.1039/c8ob02078g] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/07/2023]
Abstract
An efficient one-pot approach for the synthesis of polyfunctionalized quinolines was developed via a sequence of copper-catalyzed coupling reaction/propargyl-allenyl isomerization/aza-electrocyclization. Easily available starting materials, mild conditions, and a wide substrate scope make this approach potentially useful.
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Affiliation(s)
- Dianpeng Chen
- The Key Laboratory of Life-Organic Analysis and Key Laboratory of Pharmaceutical Intermediates and Analysis of Natural Medicine, School of Chemistry and Chemical Engineering, Qufu Normal University, Qufu 273165, Shandong, China.
| | - Xuejun Sun
- The Key Laboratory of Life-Organic Analysis and Key Laboratory of Pharmaceutical Intermediates and Analysis of Natural Medicine, School of Chemistry and Chemical Engineering, Qufu Normal University, Qufu 273165, Shandong, China.
| | - Yingying Shan
- The Key Laboratory of Life-Organic Analysis and Key Laboratory of Pharmaceutical Intermediates and Analysis of Natural Medicine, School of Chemistry and Chemical Engineering, Qufu Normal University, Qufu 273165, Shandong, China.
| | - Jinmao You
- The Key Laboratory of Life-Organic Analysis and Key Laboratory of Pharmaceutical Intermediates and Analysis of Natural Medicine, School of Chemistry and Chemical Engineering, Qufu Normal University, Qufu 273165, Shandong, China.
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16
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Zanardi MM, Biglione FA, Sortino MA, Sarotti AM. General Quantum-Based NMR Method for the Assignment of Absolute Configuration by Single or Double Derivatization: Scope and Limitations. J Org Chem 2018; 83:11839-11849. [DOI: 10.1021/acs.joc.8b01749] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- María M. Zanardi
- Área Farmacognosia, Facultad de Ciencias Bioquímicas y Farmacéuticas, Universidad Nacional de Rosario, Suipacha 531, Rosario 2000, Argentina
- Facultad de Química e Ingeniería del Rosario, Pontificia Universidad Católica Argentina, Av. Pellegrini 3314, Rosario 2000, Argentina
| | - Franco A. Biglione
- Facultad de Química e Ingeniería del Rosario, Pontificia Universidad Católica Argentina, Av. Pellegrini 3314, Rosario 2000, Argentina
| | - Maximiliano A. Sortino
- Área Farmacognosia, Facultad de Ciencias Bioquímicas y Farmacéuticas, Universidad Nacional de Rosario, Suipacha 531, Rosario 2000, Argentina
| | - Ariel M. Sarotti
- Instituto de Química Rosario (CONICET), Facultad de Ciencias Bioquímicas y Farmacéuticas, Universidad Nacional de Rosario, Suipacha 531, Rosario 2000, Argentina
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17
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Lakshmi JK, Pattnaik B, Kavitha R, Mallavadhani UV, Jagadeesh B. Conformation of flexibly linked triterpene dimers by using RDC-enhanced NMR spectroscopy. J Mol Struct 2018. [DOI: 10.1016/j.molstruc.2018.02.083] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/03/2023]
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18
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Reller M, Wesp S, Koos MRM, Reggelin M, Luy B. Biphasic Liquid Crystal and the Simultaneous Measurement of Isotropic and Anisotropic Parameters by Spatially Resolved NMR Spectroscopy. Chemistry 2017. [DOI: 10.1002/chem.201702126] [Citation(s) in RCA: 24] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Affiliation(s)
- Malin Reller
- Institut für Organische Chemie and Institut für Biologische Grenzflächen 4 - Magnetische Resonanz; Karlsruher Institut für Technologie (KIT); Fritz-Haber-Weg 6 76131 Karlsruhe Germany
| | - Svenja Wesp
- Organische Chemie; Technische Universität Darmstadt; Alarich-Weiss Str. 4 64287 Darmstadt Germany
| | - Martin R. M. Koos
- Institut für Organische Chemie and Institut für Biologische Grenzflächen 4 - Magnetische Resonanz; Karlsruher Institut für Technologie (KIT); Fritz-Haber-Weg 6 76131 Karlsruhe Germany
| | - Michael Reggelin
- Organische Chemie; Technische Universität Darmstadt; Alarich-Weiss Str. 4 64287 Darmstadt Germany
| | - Burkhard Luy
- Institut für Organische Chemie and Institut für Biologische Grenzflächen 4 - Magnetische Resonanz; Karlsruher Institut für Technologie (KIT); Fritz-Haber-Weg 6 76131 Karlsruhe Germany
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19
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Bai XF, Zou JF, Chen MY, Xu Z, Li L, Cui YM, Zheng ZJ, Xu LW. Lewis-Base-Mediated Diastereoselective Silylations of Alcohols: Synthesis of Silicon-Stereogenic Dialkoxysilanes Controlled by Chiral Aryl BINMOLs. Chem Asian J 2017; 12:1730-1735. [DOI: 10.1002/asia.201700640] [Citation(s) in RCA: 22] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/28/2017] [Indexed: 11/10/2022]
Affiliation(s)
- Xing-Feng Bai
- Key Laboratory of Organosilicon Chemistry and Material Technology of Ministry of Education; Hangzhou Normal University; Hangzhou 311121 P.R. China
- Suzhou Research Institute and State Key Laboratory for Oxo Synthesis and Selective Oxidation, Lanzhou Institute of Chemical Physics; Chinese Academy of Sciences; Lanzhou 730000 P.R. China
| | - Jin-Feng Zou
- Key Laboratory of Organosilicon Chemistry and Material Technology of Ministry of Education; Hangzhou Normal University; Hangzhou 311121 P.R. China
| | - Mu-Yi Chen
- Key Laboratory of Organosilicon Chemistry and Material Technology of Ministry of Education; Hangzhou Normal University; Hangzhou 311121 P.R. China
| | - Zheng Xu
- Key Laboratory of Organosilicon Chemistry and Material Technology of Ministry of Education; Hangzhou Normal University; Hangzhou 311121 P.R. China
| | - Li Li
- Key Laboratory of Organosilicon Chemistry and Material Technology of Ministry of Education; Hangzhou Normal University; Hangzhou 311121 P.R. China
| | - Yu-Ming Cui
- Key Laboratory of Organosilicon Chemistry and Material Technology of Ministry of Education; Hangzhou Normal University; Hangzhou 311121 P.R. China
| | - Zhan-Jiang Zheng
- Key Laboratory of Organosilicon Chemistry and Material Technology of Ministry of Education; Hangzhou Normal University; Hangzhou 311121 P.R. China
| | - Li-Wen Xu
- Key Laboratory of Organosilicon Chemistry and Material Technology of Ministry of Education; Hangzhou Normal University; Hangzhou 311121 P.R. China
- Suzhou Research Institute and State Key Laboratory for Oxo Synthesis and Selective Oxidation, Lanzhou Institute of Chemical Physics; Chinese Academy of Sciences; Lanzhou 730000 P.R. China
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20
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Li GW, Cao JM, Zong W, Hu L, Hu ML, Lei X, Sun H, Tan RX. Helical Polyisocyanopeptides as Lyotropic Liquid Crystals for Measuring Residual Dipolar Couplings. Chemistry 2017; 23:7653-7656. [DOI: 10.1002/chem.201700539] [Citation(s) in RCA: 22] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/06/2017] [Indexed: 11/06/2022]
Affiliation(s)
- Gao-Wei Li
- Institute of Functional Biomolecules; State Key Laboratory of Pharmaceutical Biotechnology; Nanjing University; Nanjing 210093 P. R. China
| | - Jiang-Ming Cao
- Institute of Functional Biomolecules; State Key Laboratory of Pharmaceutical Biotechnology; Nanjing University; Nanjing 210093 P. R. China
| | - Wen Zong
- College of Chemistry & Materials Engineering; Wenzhou University; Wenzhou 325035 P. R. China
| | - Li Hu
- College of Chemistry & Materials Engineering; Wenzhou University; Wenzhou 325035 P. R. China
| | - Mao-Lin Hu
- College of Chemistry & Materials Engineering; Wenzhou University; Wenzhou 325035 P. R. China
| | - Xinxiang Lei
- School of Pharmaceutical Sciences; South Central University for Nationalities; Wuhan 430074 P. R. China
- College of Chemistry & Materials Engineering; Wenzhou University; Wenzhou 325035 P. R. China
| | - Han Sun
- Leibniz-Institut für Molekulare Pharmakologie (FMP); Robert-Roessle-Strasse 10 13125 Berlin Germany
| | - Ren Xiang Tan
- Institute of Functional Biomolecules; State Key Laboratory of Pharmaceutical Biotechnology; Nanjing University; Nanjing 210093 P. R. China
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21
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García ME, Woodruff SR, Hellemann E, Tsarevsky NV, Gil RR. Di(ethylene glycol) methyl ether methacrylate (DEGMEMA)-derived gels align small organic molecules in methanol. MAGNETIC RESONANCE IN CHEMISTRY : MRC 2017; 55:206-209. [PMID: 26763068 DOI: 10.1002/mrc.4400] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/06/2015] [Revised: 10/20/2015] [Accepted: 11/24/2015] [Indexed: 05/28/2023]
Abstract
Residual dipolar couplings (RDCs) constitute an important NMR parameter for structural elucidation in all areas of chemistry. In this study, di(ethylene glycol) methyl ether methacrylate (DEGMEMA)-based gels are introduced as alignment media for the measurement of RDCs of small organic molecules in polar solvents such as methanol. The low viscosity of methanol permits the execution of J-scaled BIRD HSQC experiments that yield very sharp lines in anisotropic conditions. The gels have excellent mechanical properties, and their compression and expansion in the swollen state can be reversed and performed multiple times. This process enables the easy loading and release of analytes. The excellent performance of these new aligning gels is demonstrated by analyzing the structure of the alkaloid retrorsine. Copyright © 2016 John Wiley & Sons, Ltd.
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Affiliation(s)
- Manuela E García
- Department of Chemistry, Carnegie Mellon University, 4400 Fifth Avenue, Pittsburgh, PA, 15213, USA
- Department of Organic Chemistry, National University of Cordoba, Medina Allende y Haya de La Torre, Cordoba, 5000, Argentina
| | - Shannon R Woodruff
- Department of Chemistry, Southern Methodist University, Dallas, TX, USA
- Center for Drug Discovery, Design, and Delivery in Dedman College, Southern Methodist University, Dallas, TX, USA
| | - Erich Hellemann
- Department of Chemistry, Carnegie Mellon University, 4400 Fifth Avenue, Pittsburgh, PA, 15213, USA
| | - Nicolay V Tsarevsky
- Department of Chemistry, Southern Methodist University, Dallas, TX, USA
- Center for Drug Discovery, Design, and Delivery in Dedman College, Southern Methodist University, Dallas, TX, USA
| | - Roberto R Gil
- Department of Chemistry, Carnegie Mellon University, 4400 Fifth Avenue, Pittsburgh, PA, 15213, USA
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22
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Rastelli EJ, Coltart DM. Asymmetric Synthesis of (+)-anti- and (-)-syn-Mefloquine Hydrochloride. J Org Chem 2016; 81:9567-9575. [PMID: 27657347 DOI: 10.1021/acs.joc.6b01476] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
The asymmetric (er > 99:1) total synthesis of (+)-anti- and (-)-syn-mefloquine hydrochloride from a common intermediate is described. The Sharpless asymmetric dihydroxylation is the key asymmetric transformation used in the synthesis of this intermediate. It is carried out on an olefin that is accessed in three steps from commercially available materials, making the overall synthetic sequence very concise. The common diol intermediate derived from the Sharpless asymmetric dihydroxylation is converted into either a trans- or cis-epoxide, and these are subsequently converted to (+)-anti- and (-)-syn-mefloquine, respectively. X-ray crystallographic analysis of derivatives of (+)-anti- and (-)-syn-mefloquine is used to lay to rest a 40 year argument regarding the absolute stereochemistry of the mefloquines. A formal asymmetric (er > 99:1) synthesis of (+)-anti-mefloquine hydrochloride is also presented that uses a Sharpless asymmetric epoxidation as a key step.
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Affiliation(s)
- Ettore J Rastelli
- Department of Chemistry, University of Houston , Houston, Texas 77204-5003, United States
| | - Don M Coltart
- Department of Chemistry, University of Houston , Houston, Texas 77204-5003, United States
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23
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Al‐Massaedh “AA, Schmidt M, Pyell U, Reinscheid UM. Elucidation of the Enantiodiscrimination Properties of a Nonracemic Chiral Alignment Medium through Gel-based Capillary Electrochromatography: Separation of the Mefloquine Stereoisomers. ChemistryOpen 2016; 5:455-459. [PMID: 27777838 PMCID: PMC5062011 DOI: 10.1002/open.201600085] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/05/2016] [Indexed: 11/07/2022] Open
Abstract
Enantiodiscrimination and enantioseparation are two highly important processes in chemistry, often performed by using NMR spectroscopy and chromatography. For a better understanding of the mechanistic details, the same system should be studied by both methods. In addition, isotropic and anisotropic NMR parameters should be obtained, the latter using alignment media so that residual dipolar couplings and chemical-shift anisotropies can be measured. Consequently, a chiral alignment medium was used for the first time in chiral gel-based capillary electrochromatography with the four stereoisomers of the antimalaria drug mefloquine as test compounds. Chromatographic data verify that enantiodiscrimination obtained with this alignment gel is caused by differences in the equilibrium constants related to associate formation. Hence, the chromatographic separation provides physicochemical data that form a basis for the understanding and optimization of alignment processes, and vice versa.
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Affiliation(s)
- “Ayat Allah” Al‐Massaedh
- Department of ChemistryUniversity of MarburgHans-Meerwein-Straße35032MarburgGermany
- Department of ChemistryFaculty of ScienceAl al-Bayt University25113MafraqJordan
| | - Manuel Schmidt
- Department of NMR-based Structural BiologyMax-Planck-Institute for Biophysical ChemistryAm Fassberg 1137077GöttingenGermany
| | - Ute Pyell
- Department of ChemistryUniversity of MarburgHans-Meerwein-Straße35032MarburgGermany
| | - Uwe M. Reinscheid
- Department of NMR-based Structural BiologyMax-Planck-Institute for Biophysical ChemistryAm Fassberg 1137077GöttingenGermany
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24
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Tzvetkova P, Luy B. Q.E.COSY: determining sign and size of small deuterium residual quadrupolar couplings using an extended E.COSY principle. MAGNETIC RESONANCE IN CHEMISTRY : MRC 2016; 54:351-357. [PMID: 26763050 DOI: 10.1002/mrc.4386] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/07/2015] [Revised: 09/30/2015] [Accepted: 10/23/2015] [Indexed: 06/05/2023]
Abstract
Residual quadrupolar couplings contain important structural information comparable with residual dipolar couplings. However, the measurement of sign and size of especially small residual quadrupolar couplings is difficult. Here, we present an extension of the E.COSY principle to spin systems consisting of a Spin 1 coupled to a spin ½ nucleus, which allows the determination of the sign of the quadrupolar coupling of the Spin 1 nucleus relative to the heteronuclear coupling between the spins. The so-called Q.E.COSY approach is demonstrated with its sign-sensitivity using variable angle NMR, stretched gels and liquid crystalline phases applied to various CD and CD3 groups. Especially the sign-sensitive measurement of residual quadrupolar couplings that remain unresolved in conventional deuterium 1D spectra is shown.
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Affiliation(s)
- Pavleta Tzvetkova
- Institute of Organic Chemistry and Institute for Biological Interfaces 4 - Magnetic Resonance, Fritz-Haber-Weg 6, 76131, Karlsruhe, Germany
| | - Burkhard Luy
- Institute of Organic Chemistry and Institute for Biological Interfaces 4 - Magnetic Resonance, Fritz-Haber-Weg 6, 76131, Karlsruhe, Germany
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25
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Liu LY, Sun H, Griesinger C, Liu JK. The Use of a Combination of RDC and Chiroptical Spectroscopy for Determination of the Absolute Configuration of Fusariumin A from the Fungus Fusarium sp. NATURAL PRODUCTS AND BIOPROSPECTING 2016; 6:41-8. [PMID: 26791752 PMCID: PMC4749523 DOI: 10.1007/s13659-015-0084-0] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/11/2015] [Accepted: 12/21/2015] [Indexed: 05/28/2023]
Abstract
A new alkylpyrrole derivative, fusariumin A (1), was isolated from the culture broth of the fungus Fusarium sp. The absolute configuration of fuasiumin A has been established as (2'R,3'R) using a combination of RDC (residual dipolar coupling)-based NMR and DFT-supported chiroptical spectroscopy. It is worth to note that in this study without the aid of the RDC analysis, an unambiguous determination of configuration and conformation was not feasible due to the excessive conformational possibilities of this open-chain compound.
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Affiliation(s)
- Liang-Yan Liu
- College of Agronomy and Biotechnology, Yunnan Agricultural University, Kunming, 650201, China
| | - Han Sun
- Department of NMR-based Structural Biology, Max-Planck-Institute of Biophysical Chemistry, Am Fassberg 11, 37077, Göttingen, Germany
- Leibniz-Institut für Molekulare Pharmakologie, 13125, Berlin, Germany
| | - Christian Griesinger
- Department of NMR-based Structural Biology, Max-Planck-Institute of Biophysical Chemistry, Am Fassberg 11, 37077, Göttingen, Germany.
| | - Ji-Kai Liu
- School of Pharmaceutical Sciences, South-Central University for Nationalities, Wuhan, 430074, China.
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26
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Reinscheid F, Schmidt M, Abromeit H, Liening S, Scriba G, Reinscheid U. Structural and chiroptical analysis of naturally occurring (–)-strychnine. J Mol Struct 2016. [DOI: 10.1016/j.molstruc.2015.10.062] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/15/2023]
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27
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Reinscheid F, Reinscheid U. Stereochemical analysis of (+)-limonene using theoretical and experimental NMR and chiroptical data. J Mol Struct 2016. [DOI: 10.1016/j.molstruc.2015.10.061] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022]
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28
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Kohout M, Vandenbussche J, Roller A, Tůma J, Bogaerts J, Bultinck P, Herrebout W, Lindner W. Absolute configuration of the antimalarial erythro-mefloquine – vibrational circular dichroism and X-ray diffraction studies of mefloquine and its thiourea derivative. RSC Adv 2016. [DOI: 10.1039/c6ra19367f] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
Abstract
The long-standing discussion of the absolute configuration of erythro-mefloquine is revisited, showcasing the strength of a combination of experimental and calculated vibrational circular dichroism spectroscopy.
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Affiliation(s)
- M. Kohout
- Department of Organic Chemistry
- University of Chemistry and Technology Prague
- Technická 5
- 166 28 Prague
- Czech Republic
| | - J. Vandenbussche
- Department of Inorganic and Physical Chemistry
- Ghent University
- 9000 Ghent
- Belgium
| | - A. Roller
- Institute of Inorganic Chemistry
- University of Vienna
- 1090 Vienna
- Austria
| | - J. Tůma
- Department of Organic Chemistry
- University of Chemistry and Technology Prague
- Technická 5
- 166 28 Prague
- Czech Republic
| | - J. Bogaerts
- Department of Chemistry
- University of Antwerp
- 2020 Antwerp
- Belgium
| | - P. Bultinck
- Department of Inorganic and Physical Chemistry
- Ghent University
- 9000 Ghent
- Belgium
| | - W. Herrebout
- Department of Chemistry
- University of Antwerp
- 2020 Antwerp
- Belgium
| | - W. Lindner
- Institute of Analytical Chemistry
- University of Vienna
- 1090 Vienna
- Austria
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29
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Chen ZY, Shen FY, Jiang L, Zhao X, Shen XL, Zhong W, Liu S, Wang ZR, Wang YW. Attenuation of Neuropathic Pain by Inhibiting Electrical Synapses in the Anterior Cingulate Cortex. Anesthesiology 2016; 124:169-83. [PMID: 26566282 DOI: 10.1097/aln.0000000000000942] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023]
Abstract
BACKGROUND Synaptic mechanisms and neuronal oscillations have been proposed to be responsible for neuropathic pain formation. Many studies have also highlighted the important role of electrical synapses in synaptic plasticity and in neuronal oscillations. Thus, electrical synapses may contribute to neuropathic pain generation. However, previous studies have primarily focused on the role of chemical synapses, while ignoring the role of electrical synapses, in neuropathic pain generation. METHODS The authors adopted microinjection, RNA interference techniques, and behavioral tests to verify the link between connexin 36 (Cx36) and neuropathic pain. They also studied the selective Cx36 blocker mefloquine in rat chronic constriction injury and spared nerve injury model of neuropathic pain. Electrophysiologic recordings were used to further confirm the behavioral data. RESULTS The authors found that Cx36, which constitutes the neuron-neuron electrical synapses, was up-regulated in the anterior cingulate cortex after nerve injury (n = 5). Meanwhile, Cx36-mediated neuronal oscillations in the gamma frequency range (30 to 80 Hz) (n = 7 to 8) and the neuronal synaptic transmission (n = 13 to 19) were also enhanced. Neuropathic pain was relieved by disrupting Cx36 function or expression in the anterior cingulate cortex. They also found that mefloquine, which are clinically used for treating malaria, affected gamma oscillations and synaptic plasticity, leading to a sustained pain relief in chronic constriction injury and spared nerve injury models (n = 7 to 12). CONCLUSION The electrical synapses blocker mefloquine could affect gamma oscillations and synaptic plasticity in the anterior cingulate cortex and relieve neuropathic pain. Cx36 may be a new therapeutic target for treating chronic pain.
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Affiliation(s)
- Zhi-Yu Chen
- From the Department of Anesthesiology and Intensive Care Medicine, Xinhua Hospital, College of Medicine, Shanghai Jiaotong University, Shanghai, China (Z.-Y.C., F.-Y.S., L.J., X.Z., X.-L.S., Y.-W.W.); and Laboratory of Neural Circuit Plasticity & Memory, Institute of Brain Functional Genomics, East China Normal University, Shanghai, China (W.Z., S.L., Z.-R.W.)
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30
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Lauterwasser EMW, Fontaine SD, Li H, Gut J, Katneni K, Charman SA, Rosenthal PJ, Bogyo M, Renslo AR. Trioxolane-Mediated Delivery of Mefloquine Limits Brain Exposure in a Mouse Model of Malaria. ACS Med Chem Lett 2015; 6:1145-9. [PMID: 26617969 DOI: 10.1021/acsmedchemlett.5b00296] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/22/2015] [Accepted: 10/02/2015] [Indexed: 11/29/2022] Open
Abstract
Peroxidic antimalarial agents including the sequiterpene artemisinins and the synthetic 1,2,4-trioxolanes function via initial intraparasitic reduction of an endoperoxide bond. By chemically coupling this reduction to release of a tethered drug species it is possible to confer two distinct pharmacological effects in a parasite-selective fashion, both in vitro and in vivo. Here we demonstrate the trioxolane-mediated delivery of the antimalarial agent mefloquine in a mouse malaria model. Selective partitioning of the trioxolane-mefloquine conjugate in parasitized erythrocytes, combined with effective exclusion of the conjugate from brain significantly reduced brain exposure as compared to mice directly administered mefloquine. These studies suggest the potential of trioxolane-mediated drug delivery to mitigate off-target effects of existing drugs, including the adverse neuropsychiatric effects of mefloquine use in therapeutic and chemoprophylactic settings.
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Affiliation(s)
| | | | - Hao Li
- Departments
of Pathology and Microbiology and Immunology, Stanford School of Medicine, 300 Pasteur Drive, Stanford, California 94305, United States
| | | | - Kasiram Katneni
- Centre for Drug Candidate Optimisation,
Monash Institute of Pharmaceutical Sciences, Monash University, Parkville, VIC 3052, Australia
| | - Susan A. Charman
- Centre for Drug Candidate Optimisation,
Monash Institute of Pharmaceutical Sciences, Monash University, Parkville, VIC 3052, Australia
| | | | - Matthew Bogyo
- Departments
of Pathology and Microbiology and Immunology, Stanford School of Medicine, 300 Pasteur Drive, Stanford, California 94305, United States
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31
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Rastelli EJ, Coltart DM. A Concise and Highly Enantioselective Total Synthesis of (+)-anti- and (-)-syn-Mefloquine Hydrochloride: Definitive Absolute Stereochemical Assignment of the Mefloquines. Angew Chem Int Ed Engl 2015; 54:14070-4. [PMID: 26422780 DOI: 10.1002/anie.201507304] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/05/2015] [Indexed: 11/09/2022]
Abstract
A concise asymmetric (>99:1 e.r.) total synthesis of (+)-anti- and (-)-syn-mefloquine hydrochloride from a common intermediate is described. The key asymmetric transformation is a Sharpless dihydroxylation of an olefin that is accessed in three steps from commercially available materials. The Sharpless-derived diol is converted into either a trans or cis epoxide, and these are subsequently converted into (+)-anti- and (-)-syn-mefloquine, respectively. The synthetic (+)-anti- and (-)-syn-mefloquine samples were derivatized with (S)-(+)-mandelic acid tert-butyldimethylsilyl ether, and a crystal structure of each derivative was obtained. These are the first X-ray structures for mefloquine derivatives that were obtained by coupling to a known chiral, nonracemic compound, and provide definitive confirmation of the absolute stereochemistry of (+)-anti- as well as (-)-syn-mefloquine.
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Affiliation(s)
| | - Don M Coltart
- Department of Chemistry, University of Houston, Houston, TX (USA).
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Rastelli EJ, Coltart DM. A Concise and Highly Enantioselective Total Synthesis of (+)‐
anti
‐ and (−)‐
syn
‐Mefloquine Hydrochloride: Definitive Absolute Stereochemical Assignment of the Mefloquines. Angew Chem Int Ed Engl 2015. [DOI: 10.1002/ange.201507304] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
Affiliation(s)
| | - Don M. Coltart
- Department of Chemistry, University of Houston, Houston, TX (USA)
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Lesot P, Aroulanda C, Zimmermann H, Luz Z. Enantiotopic discrimination in the NMR spectrum of prochiral solutes in chiral liquid crystals. Chem Soc Rev 2015; 44:2330-75. [DOI: 10.1039/c4cs00260a] [Citation(s) in RCA: 91] [Impact Index Per Article: 10.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Theory and applications to stereo- and bio-chemistry of the discrimination of enantiotopic elements observed in the NMR spectra of prochiral solutes dissolved in chiral liquid crystals are comprehensively discussed.
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Affiliation(s)
- Philippe Lesot
- Laboratoire de RMN en Milieu Orienté CNRS UMR 8182
- ICMMO
- 91405 Orsay cedex
- France
| | - Christie Aroulanda
- Laboratoire de RMN en Milieu Orienté CNRS UMR 8182
- ICMMO
- 91405 Orsay cedex
- France
| | - Herbert Zimmermann
- Abteilung Biophysik
- Max-Planck-Institut für Medizinische Forschung
- 69120 Heidelberg
- Germany
| | - Zeev Luz
- Weizmann Institute of Science
- Department of Chemical Physics
- Rehovot 76100
- Israel
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Mendes do Prado V, Cardoso Seiceira R, Pitaluga Jr A, Andrade-Filho T, Andrade Alves W, Reily Rocha A, Furlan Ferreira F. Elucidating the crystal structure of the antimalarial drug (±)-mefloquine hydrochloride: a tetragonal hydrated species. J Appl Crystallogr 2014. [DOI: 10.1107/s160057671401303x] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022] Open
Abstract
Albeit widely studied, the structure of the antimalarial drug (±)-mefloquine hydrochloride is still a controversial issue. A combination of X-ray powder diffraction, theoretical calculations and Fourier transform–infrared spectroscopy is used to unambiguously determine the crystal structure of the molecule in its active pharmaceutical ingredient. It is demonstrated that water is incorporated into the structure, leading to a hydrated form and, most importantly, to significant differences in both structure and bonding. Such changes can lead to significant differences in biological activity.
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Schmidt M, Reinscheid F, Sun H, Abromeit H, Scriba GKE, Sönnichsen FD, John M, Reinscheid UM. Hidden Flexibility of Strychnine. European J Org Chem 2014. [DOI: 10.1002/ejoc.201301760] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/04/2023]
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Zhou G, Liu X, Liu X, Nie H, Zhang S, Chen W. A Stereospecific Synthesis and Unambiguous Assignment of the Absolute Configuration of (−)‐
erythro
‐Mefloquine Hydrochloride. Adv Synth Catal 2013. [DOI: 10.1002/adsc.201300531] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Affiliation(s)
- Gang Zhou
- School of Pharmacy, Fourth Military Medical University,169 Changle West Road, Xi'an 710032, People's Republic of China
| | - Xian Liu
- School of Pharmacy, Fourth Military Medical University,169 Changle West Road, Xi'an 710032, People's Republic of China
| | - Xueying Liu
- School of Pharmacy, Fourth Military Medical University,169 Changle West Road, Xi'an 710032, People's Republic of China
| | - Huifang Nie
- School of Pharmacy, Fourth Military Medical University,169 Changle West Road, Xi'an 710032, People's Republic of China
| | - Shengyong Zhang
- School of Pharmacy, Fourth Military Medical University,169 Changle West Road, Xi'an 710032, People's Republic of China
| | - Weiping Chen
- School of Pharmacy, Fourth Military Medical University,169 Changle West Road, Xi'an 710032, People's Republic of China
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Kakita VMR, Rachineni K, Bharatam J. Unambiguous determination of conformation and relative configuration of a multiple stereo-centre molecule Rifamycin-S by using scaled residual dipolar couplings: A case study. J Mol Struct 2013. [DOI: 10.1016/j.molstruc.2013.08.061] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/26/2022]
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Schützenmeister N, Müller M, Reinscheid UM, Griesinger C, Leonov A. Trapped in misbelief for almost 40 years: selective synthesis of the four stereoisomers of mefloquine. Chemistry 2013; 19:17584-8. [PMID: 24226934 DOI: 10.1002/chem.201303403] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/29/2013] [Indexed: 11/09/2022]
Abstract
Here we report the synthesis of all four stereoisomers of mefloquine. Mefloquine (Lariam) is an important anti-malaria drug that is applied as a racemate of the erythro form. However, the (-)-isomer induces psychosis, while the (+)-enantiomer does not have this undesired side effect. There are six syntheses of which five lead to the wrong enantiomer without the authors of these syntheses noting that they had synthesized the wrong compound. At the same time physical chemistry investigations had assigned the absolute configuration correctly and the last enantioselective synthesis that took these results into account delivered the correct absolute configuration. Since various synthetic approaches failed to provide the correct stereoisomers in previous syntheses, we submit here a synthetic approach with a domino Sonogashira-6π-electrocyclisation as key step that confirmed synthetically the correct absolute configuration of all four isomers.
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Affiliation(s)
- Nina Schützenmeister
- Max-Planck-Institute of Biophysical Chemistry, Department of NMR-Based Structural Biology, Am Fassberg 11, 37077 Göttingen (Germany), Fax: (+49) 551 201-2202
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Ding J, Hall DG. Concise Synthesis and Antimalarial Activity of All Four Mefloquine Stereoisomers Using a Highly Enantioselective Catalytic Borylative Alkene Isomerization. Angew Chem Int Ed Engl 2013. [DOI: 10.1002/ange.201303931] [Citation(s) in RCA: 27] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
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40
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Ding J, Hall DG. Concise synthesis and antimalarial activity of all four mefloquine stereoisomers using a highly enantioselective catalytic borylative alkene isomerization. Angew Chem Int Ed Engl 2013; 52:8069-73. [PMID: 23818420 DOI: 10.1002/anie.201303931] [Citation(s) in RCA: 63] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/08/2013] [Indexed: 11/07/2022]
Affiliation(s)
- Jinyue Ding
- Department of Chemistry, University of Alberta, Gunning-Lemieux Chemistry Centre, 4-010 Centennial Centre for Interdisciplinary Science, Edmonton, Alberta, T6G 2G2, Canada
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Dassonville-Klimpt A, Cézard C, Mullié C, Agnamey P, Jonet A, Da Nascimento S, Marchivie M, Guillon J, Sonnet P. Absolute Configuration and Antimalarial Activity of erythro-Mefloquine Enantiomers. Chempluschem 2013; 78:642-646. [PMID: 31986621 DOI: 10.1002/cplu.201300074] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/22/2013] [Revised: 06/17/2013] [Indexed: 11/11/2022]
Abstract
Mefloquine (MQ), an antimalarial drug, is used as a racemate of (-)- and (+)-enantiomers, which display biological differences. The question concerning their exact configuration remains a matter of debate. The absolute configuration of the two MQ enantiomers as well as their biological activity has been established, thus confirming the importance of the stereochemistry in the design of MQ analogues that have fewer adverse side effects.
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Affiliation(s)
- Alexandra Dassonville-Klimpt
- Laboratoire des Glucides, CNRS FRE 3517, UFR de Pharmacie, Université de Picardie Jules Verne, 1, rue des Louvels, 80037 Amiens cedex 01 (France), Fax: (+33) 322827469
| | - Christine Cézard
- Laboratoire des Glucides, CNRS FRE 3517, UFR de Pharmacie, Université de Picardie Jules Verne, 1, rue des Louvels, 80037 Amiens cedex 01 (France), Fax: (+33) 322827469
| | - Catherine Mullié
- Laboratoire des Glucides, CNRS FRE 3517, UFR de Pharmacie, Université de Picardie Jules Verne, 1, rue des Louvels, 80037 Amiens cedex 01 (France), Fax: (+33) 322827469
| | - Patrice Agnamey
- Laboratoire des Glucides, CNRS FRE 3517, UFR de Pharmacie, Université de Picardie Jules Verne, 1, rue des Louvels, 80037 Amiens cedex 01 (France), Fax: (+33) 322827469
| | - Alexia Jonet
- Laboratoire des Glucides, CNRS FRE 3517, UFR de Pharmacie, Université de Picardie Jules Verne, 1, rue des Louvels, 80037 Amiens cedex 01 (France), Fax: (+33) 322827469
| | - Sophie Da Nascimento
- Laboratoire des Glucides, CNRS FRE 3517, UFR de Pharmacie, Université de Picardie Jules Verne, 1, rue des Louvels, 80037 Amiens cedex 01 (France), Fax: (+33) 322827469
| | - Mathieu Marchivie
- CNRS FRE 3396-Pharmacochimie, UFR de Pharmacie, Université Bordeaux Segalen, 33076 Bordeaux cedex (France)
| | - Jean Guillon
- CNRS FRE 3396-Pharmacochimie, UFR de Pharmacie, Université Bordeaux Segalen, 33076 Bordeaux cedex (France)
| | - Pascal Sonnet
- Laboratoire des Glucides, CNRS FRE 3517, UFR de Pharmacie, Université de Picardie Jules Verne, 1, rue des Louvels, 80037 Amiens cedex 01 (France), Fax: (+33) 322827469
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Schmidts V, Fredersdorf M, Lübken T, Porzel A, Arnold N, Wessjohann L, Thiele CM. RDC-based determination of the relative configuration of the fungicidal cyclopentenone 4,6-diacetylhygrophorone A12. JOURNAL OF NATURAL PRODUCTS 2013; 76:839-844. [PMID: 23659349 DOI: 10.1021/np300728b] [Citation(s) in RCA: 27] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/28/2023]
Abstract
The hygrophorones, a class of cyclopentenones isolated from fruiting bodies of the genus Hygrophorus (basidiomycetes), show promising antifungal activity. While the constitution of 4,6-diacetylhygrophorone A(12) (3) and the relative configuration of the stereogenic centers in the cyclopentenone ring were elucidated using standard NMR and MS techniques, the relative configuration of the exocyclic stereogenic center could not be assigned. By introducing a sample of 3 into an alignment medium and measuring anisotropic NMR parameters, namely, residual dipolar couplings, we were able to unambiguously determine the relative configuration of all three stereogenic centers in 4,6-diacetylhygrophorone A(12) simultaneously by fitting several structure proposals to the experimental data.
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Affiliation(s)
- Volker Schmidts
- Clemens Schöpf Institute for Organic Chemistry and Biochemistry, Technische Universität Darmstadt, Petersenstraße 22, Darmstadt, Germany
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Biamonte MA, Wanner J, Le Roch KG. Recent advances in malaria drug discovery. Bioorg Med Chem Lett 2013; 23:2829-43. [PMID: 23587422 PMCID: PMC3762334 DOI: 10.1016/j.bmcl.2013.03.067] [Citation(s) in RCA: 129] [Impact Index Per Article: 11.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/15/2013] [Revised: 03/11/2013] [Accepted: 03/20/2013] [Indexed: 01/18/2023]
Abstract
This digest covers some of the most relevant progress in malaria drug discovery published between 2010 and 2012. There is an urgent need to develop new antimalarial drugs. Such drugs can target the blood stage of the disease to alleviate the symptoms, the liver stage to prevent relapses, and the transmission stage to protect other humans. The pipeline for the blood stage is becoming robust, but this should not be a source of complacency, as the current therapies set a high standard. Drug discovery efforts directed towards the liver and transmission stages are in their infancy but are receiving increasing attention as targeting these stages could be instrumental in eradicating malaria.
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Affiliation(s)
- Marco A Biamonte
- Drug Discovery for Tropical Diseases, Suite 230, San Diego, CA 92121, USA.
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Müller M, Orben CM, Schützenmeister N, Schmidt M, Leonov A, Reinscheid UM, Dittrich B, Griesinger C. The absolute configuration of (+)- and (-)-erythro-mefloquine. Angew Chem Int Ed Engl 2013; 52:6047-9. [PMID: 23616269 DOI: 10.1002/anie.201300258] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/11/2013] [Indexed: 11/05/2022]
Abstract
The controversy over the absolute configuration of (+)-erythro-mefloquine, the less psychosis-causing enantiomer of the anti-malarial drug Lariam, has been resolved by Mosher ester crystallization. The configuration determined previously by physical methods is correct, whereas the configuration determined by three enantioselective syntheses is wrong.
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Affiliation(s)
- Michael Müller
- Max-Planck-Institut für Biophysikalische Chemie, Department of NMR-Based Structural Biology, Am Fassberg 11, 37077 Göttingen, Germany
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46
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Navarro-Vázquez A. MSpin-RDC. A program for the use of residual dipolar couplings for structure elucidation of small molecules. MAGNETIC RESONANCE IN CHEMISTRY : MRC 2012; 50 Suppl 1:S73-S79. [PMID: 23280663 DOI: 10.1002/mrc.3905] [Citation(s) in RCA: 103] [Impact Index Per Article: 8.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/25/2012] [Revised: 10/24/2012] [Accepted: 11/06/2012] [Indexed: 05/28/2023]
Abstract
We developed a new program, MSpin-RDC for the analysis of residual dipolar coupling data. This software, specially designed for small molecule analysis, can directly read many molecular-modeling and popular chemistry file formats and accept RDC values as a simple free-format table. Alignment tensor can then be computed by singular value decomposition, as well as predicted using inertia and gyration tensor-based methodologies. Trial structures are then ranked according to their Cornilescu's quality factor (Q) values. Analysis of multiconformational problems and fitting of RDC data to relative populations can be accomplished using the single-tensor approximation.
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Affiliation(s)
- Armando Navarro-Vázquez
- Departamento de Química Orgánica, Facultade de Química, Universidade de Santiago de Compostela, Santiago de Compostela, Spain
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48
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Trigo-Mouriño P, Navarro-Vázquez A, Sánchez-Pedregal VM. Influence of solvent and salt concentration on the alignment properties of acrylamide copolymer gels for the measurement of RDC. MAGNETIC RESONANCE IN CHEMISTRY : MRC 2012; 50 Suppl 1:S29-S37. [PMID: 23280658 DOI: 10.1002/mrc.3889] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/03/2012] [Revised: 09/11/2012] [Accepted: 09/21/2012] [Indexed: 06/01/2023]
Abstract
The dependence of molecular alignment with solvent nature and salt concentration has been investigated for mechanically stretched polyacrylamide copolymer gels. Residual dipolar couplings (RDCs) were recorded for D(2)O, DMSO-d(6), and DMSO-d(6)/D(2)O solutions containing different proportions of the solvents and different sodium chloride concentrations. Alignment tensors were determined by fitting the experimental RDCs to the DFT-computed structure of N-methylcodeinium ion. Analysis of the tensors shows that the degree of alignment decreases with the proportion of DMSO-d(6) as well as with the concentration of sodium chloride, most likely due to enhanced ion-pair aggregation. Furthermore, rotation of the alignment tensor is observed when increasing the salt concentration.
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Affiliation(s)
- Pablo Trigo-Mouriño
- Centro Singular de Investigación en Química Biolóxica e Materiais Moleculares, Universidade de Santiago de Compostela, Campus Vida, 15782, Santiago de Compostela, Spain
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49
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Schmidt M, Sun H, Leonov A, Griesinger C, Reinscheid UM. Chiral discrimination of amines by anisotropic NMR parameters using chiral polyacrylamide-based gels. MAGNETIC RESONANCE IN CHEMISTRY : MRC 2012; 50 Suppl 1:S38-S44. [PMID: 23280659 DOI: 10.1002/mrc.3886] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/22/2012] [Revised: 09/01/2012] [Accepted: 09/14/2012] [Indexed: 05/28/2023]
Abstract
A new chiral alignment medium for dimethyl sulfoxide, methanol, and water as solvents was developed. Because both enantiomers of the gel are available, it is possible to enantiodiscriminate natural products such as strychnine HCl that naturally occurs as single enantiomer. With the two methods of achieving anisotropy, namely stretching and confinement, the degree of alignment can be adjusted, and the director changed from horizontal to vertical. This increases the applicability. Three compounds were enantiodiscriminated on the basis of residual dipolar coupling data: mefloquine HCl, strychnine HCl, and menthylamine HCl.
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Affiliation(s)
- Manuel Schmidt
- Max Planck Institute for Biophysical Chemistry, NMR II, 37077 Göttingen, Germany
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