1
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Charpentier MD, Venkatramanan R, Rougeot C, Leyssens T, Johnston K, ter Horst JH. Multicomponent Chiral Quantification with Ultraviolet Circular Dichroism Spectroscopy: Ternary and Quaternary Phase Diagrams of Levetiracetam. Mol Pharm 2023; 20:616-629. [PMID: 36468979 PMCID: PMC9811458 DOI: 10.1021/acs.molpharmaceut.2c00825] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/07/2022]
Abstract
Chiral molecules are challenging for the pharmaceutical industry because although physical properties of the enantiomers are the same in achiral systems, they exhibit different effects in chiral systems, such as the human body. The separation of enantiomers is desired but complex, as enantiomers crystallize most often as racemic compounds. A technique to enable the chiral separation of racemic compounds is to create an asymmetry in the thermodynamic system by generating chiral cocrystal(s) using a chiral coformer and using the solubility differences to enable separation through crystallization from solution. However, such quaternary systems are complex and require analytical methods to quantify different chiral molecules in solution. Here, we develop a new chiral quantification method using ultraviolet-circular dichroism spectroscopy and multivariate partial least squares calibration models, to build multicomponent chiral phase diagrams. Working on the quaternary system of (R)- and (S)-2-(2-oxopyrrolidin-1-yl)butanamide enantiomers with (S)-mandelic acid in acetonitrile, we measure accurately the full quaternary phase diagram for the first time. By understanding the phase stabilities of the racemic compound and the enantiospecific cocrystal, the chiral resolution of levetiracetam could be designed due to a large asymmetry in overall solubility between both sides of the racemic composition. This new method offers improvements for chiral molecule quantification in complex multicomponent chiral systems and can be applied to other chiral spectroscopy techniques.
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Affiliation(s)
- Maxime D. Charpentier
- EPSRC
Centre for Innovative Manufacturing in Continuous Manufacturing and
Crystallization (CMAC), University of Strathclyde,
Technology and Innovation Centre, 99 George Street, GlasgowG1 1RD, U.K.,
| | - Raghunath Venkatramanan
- EPSRC
Centre for Innovative Manufacturing in Continuous Manufacturing and
Crystallization (CMAC), University of Strathclyde,
Technology and Innovation Centre, 99 George Street, GlasgowG1 1RD, U.K.
| | - Céline Rougeot
- UCB
Pharma SA, chemin du Foriest, 1420 Braine-L’Alleud, Brussels1070, Belgium
| | - Tom Leyssens
- Institute
of Condensed Matter and Nanosciences, UCLouvain, Place L. Pasteur 1, Brussels1070, Belgium
| | - Karen Johnston
- Department
of Chemical and Process Engineering, University
of Strathclyde, James Weir Building, 75 Montrose Street, GlasgowG1 1XJ, U.K.
| | - Joop H. ter Horst
- EPSRC
Centre for Innovative Manufacturing in Continuous Manufacturing and
Crystallization (CMAC), University of Strathclyde,
Technology and Innovation Centre, 99 George Street, GlasgowG1 1RD, U.K.,Laboratoire
Sciences et Méthodes Séparatives (SMS), Univ Rouen Normandie, UR 3233, F-76000Rouen, France
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2
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Charpentier MD, Devogelaer JJ, Tijink A, Meekes H, Tinnemans P, Vlieg E, de Gelder R, Johnston K, ter Horst JH. Comparing and Quantifying the Efficiency of Cocrystal Screening Methods for Praziquantel. CRYSTAL GROWTH & DESIGN 2022; 22:5511-5525. [PMID: 36097547 PMCID: PMC9460446 DOI: 10.1021/acs.cgd.2c00615] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 05/31/2022] [Revised: 08/15/2022] [Indexed: 06/15/2023]
Abstract
Pharmaceutical cocrystals are highly interesting due to their effect on physicochemical properties and their role in separation technologies, particularly for chiral molecules. Detection of new cocrystals is a challenge, and robust screening methods are required. As numerous techniques exist that differ in their crystallization mechanisms, their efficiencies depend on the coformers investigated. The most important parameters characterizing the methods are the (a) screenable coformer fraction, (b) coformer success rate, (c) ability to give several cocrystals per successful coformer, (d) identification of new stable phases, and (e) experimental convenience. Based on these parameters, we compare and quantify the performance of three methods: liquid-assisted grinding, solvent evaporation, and saturation temperature measurements of mixtures. These methods were used to screen 30 molecules, predicted by a network-based link prediction algorithm (described in Cryst. Growth Des. 2021, 21(6), 3428-3437) as potential coformers for the target molecule praziquantel. The solvent evaporation method presented more drawbacks than advantages, liquid-assisted grinding emerged as the most successful and the quickest, while saturation temperature measurements provided equally good results in a slower route yielding additional solubility information relevant for future screenings, single-crystal growth, and cocrystal production processes. Seventeen cocrystals were found, with 14 showing stability and 12 structures resolved.
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Affiliation(s)
- Maxime D. Charpentier
- EPSRC
Centre for Innovative Manufacturing in Continuous Manufacturing and
Crystallization (CMAC), University of Strathclyde,
Technology and Innovation Centre, 99 George Street, Glasgow G1 1RD, U.K..
| | - Jan-Joris Devogelaer
- Institute
for Molecules and Materials, Radboud University, Heyendaalseweg 135, 6525AJ Nijmegen, The Netherlands
| | - Arnoud Tijink
- Institute
for Molecules and Materials, Radboud University, Heyendaalseweg 135, 6525AJ Nijmegen, The Netherlands
| | - Hugo Meekes
- Institute
for Molecules and Materials, Radboud University, Heyendaalseweg 135, 6525AJ Nijmegen, The Netherlands
| | - Paul Tinnemans
- Institute
for Molecules and Materials, Radboud University, Heyendaalseweg 135, 6525AJ Nijmegen, The Netherlands
| | - Elias Vlieg
- Institute
for Molecules and Materials, Radboud University, Heyendaalseweg 135, 6525AJ Nijmegen, The Netherlands
| | - René de Gelder
- Institute
for Molecules and Materials, Radboud University, Heyendaalseweg 135, 6525AJ Nijmegen, The Netherlands
| | - Karen Johnston
- Department
of Chemical and Process Engineering, University
of Strathclyde, James Weir Building, 75 Montrose Street, Glasgow G1 1XJ, U.K.
| | - Joop H. ter Horst
- EPSRC
Centre for Innovative Manufacturing in Continuous Manufacturing and
Crystallization (CMAC), University of Strathclyde,
Technology and Innovation Centre, 99 George Street, Glasgow G1 1RD, U.K..
- Laboratoire
Sciences et Méthodes Séparatives, Université de Rouen Normandie, Place Emile Blondel, 76821 Mont Saint Aignan Cedex, France
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3
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Ong CS, Oor JZ, Tan SJ, Chew JW. Enantiomeric Separation of Racemic Mixtures Using Chiral-Selective and Organic-Solvent-Resistant Thin-Film Composite Membranes. ACS APPLIED MATERIALS & INTERFACES 2022; 14:10875-10885. [PMID: 35175724 DOI: 10.1021/acsami.1c25175] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/14/2023]
Abstract
Membrane-based chiral separation has emerged as a promising method for the efficient separation of chiral molecules. Ideally, the membranes should be able to achieve good enantioselectivity, while maintaining high stability in harsh solvents. However, engineering membranes for chiral molecular separation in harsh organic solvent environments is still a big challenge. In this study, we fabricated a novel thin-film composite nanofiltration membrane composed of (2-hydroxypropyl)-beta-cyclodextrin (HP-β-CD) as the chiral selector for the enantiomeric separation of racemic 1-phenylethanol chiral compounds in organic solvents. The fabricated membrane achieved 60-80% enantioselectivity of R-phenylethanol over S-phenylethanol in nonpolar n-hexane. It was found that HP-β-CD played a critical role in the enantioselective performance, as the membrane without HP-β-CD showed no chiral selectivity. Molecular docking calculations substantiate the experiments by showing that the average free binding energy of S-phenylethanol with HP-β-CD is stronger than that of R-phenylethanol, indicating that the complex of S-phenylethanol with HP-β-CD has a higher thermodynamic stability and greater interaction. Furthermore, the crosslinked network between HP-β-CD and the polyamide layer conferred the membrane with solvent stability in nonpolar solvents. Moreover, this new membrane exhibited good solvent permeance and a molecular weight cutoff of around 650 g mol-1.
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Affiliation(s)
- Chi Siang Ong
- School of Chemical and Biomedical Engineering, Nanyang Technological University, 62 Nanyang Drive, Singapore 637459, Singapore
| | - Jia Zheng Oor
- School of Chemical and Biomedical Engineering, Nanyang Technological University, 62 Nanyang Drive, Singapore 637459, Singapore
- Singapore Membrane Technology Centre, Nanyang Environmental and Water Research Institute, Nanyang Technological University, Singapore 637141, Singapore
| | - Shiliang Johnathan Tan
- School of Chemical and Biomedical Engineering, Nanyang Technological University, 62 Nanyang Drive, Singapore 637459, Singapore
| | - Jia Wei Chew
- School of Chemical and Biomedical Engineering, Nanyang Technological University, 62 Nanyang Drive, Singapore 637459, Singapore
- Singapore Membrane Technology Centre, Nanyang Environmental and Water Research Institute, Nanyang Technological University, Singapore 637141, Singapore
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4
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Zhang Y, Liu C, Xu W, Quan P, Luo Z, Yang D, Fang L. An investigation on percutaneous permeation of flurbiprofen enantiomers: The role of molecular interaction between drug and skin components. Int J Pharm 2021; 601:120503. [PMID: 33746012 DOI: 10.1016/j.ijpharm.2021.120503] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/08/2021] [Revised: 03/03/2021] [Accepted: 03/13/2021] [Indexed: 01/07/2023]
Abstract
This work aimed to investigate skin permeation profiles of chiral flurbiprofen and clarify the molecular mechanism of transdermal permeation difference of enantiomers. The in vitro transdermal permeation of enantiomers through rat skin was studied by diffusion cells. Physicochemical parameters of model chiral drugs were determined. Molecular interaction between chiral flurbiprofen and ceramides of skin was investigated by FTIR, 13C NMR and molecular docking. The skin permeation mechanism of chiral drugs was characterized by ATR-FTIR, Raman spectra, DSC and molecular dynamic simulation. The results showed that the amount of the permeation and retention amount of (S)-flurbiprofen was 1.5 times over that of (R)-flurbiprofen. And it was proven that the difference was not induced by physicochemical properties but the molecular interaction between drug-skin components. (S)-flurbiprofen was easy to form stronger hydrogen bonding with -CONH group of skin lipids due to its steric configuration, which disturbed lipids arrangement more easily according to the results of ATR-FTIR (ΔνasCH2 = 1.00 cm-1), Raman spectra (ΔI2882/I2853 = 0.32) and the DSC (ΔTm stratum corneum = 11.75 °C). It was demonstrated more obvious effect on the second structure of keratin by ATR-FTIR study (Δ Amide I = 3.60 cm-1 and Δ Amide II = 3.38 cm-1). Better compatibility between (S)-flurbiprofen and lipids was confirmed quantificationally by thermodynamic analysis. In conclusion, the higher interaction between (S)-flurbiprofen and skin components, the higher skin permeation, which contributes to decrease the administration dose and increase the therapeutic effect.
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Affiliation(s)
- Yang Zhang
- Department of Pharmaceutical Sciences, Shenyang Pharmaceutical University, 103 Wenhua Road, Shenyang, Liaoning 110016, China
| | - Chao Liu
- Department of Pharmaceutical Sciences, Shenyang Pharmaceutical University, 103 Wenhua Road, Shenyang, Liaoning 110016, China
| | - Wenwen Xu
- Department of Pharmaceutical Sciences, Shenyang Pharmaceutical University, 103 Wenhua Road, Shenyang, Liaoning 110016, China
| | - Peng Quan
- Department of Pharmaceutical Sciences, Shenyang Pharmaceutical University, 103 Wenhua Road, Shenyang, Liaoning 110016, China
| | - Zheng Luo
- Department of Pharmaceutical Sciences, Shenyang Pharmaceutical University, 103 Wenhua Road, Shenyang, Liaoning 110016, China
| | - Degong Yang
- Department of Pharmaceutical Sciences, Shenyang Pharmaceutical University, 103 Wenhua Road, Shenyang, Liaoning 110016, China
| | - Liang Fang
- Department of Pharmaceutical Sciences, Shenyang Pharmaceutical University, 103 Wenhua Road, Shenyang, Liaoning 110016, China.
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5
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Barzkar N, Sohail M, Tamadoni Jahromi S, Gozari M, Poormozaffar S, Nahavandi R, Hafezieh M. Marine Bacterial Esterases: Emerging Biocatalysts for Industrial Applications. Appl Biochem Biotechnol 2021; 193:1187-1214. [PMID: 33411134 DOI: 10.1007/s12010-020-03483-8] [Citation(s) in RCA: 25] [Impact Index Per Article: 8.3] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/17/2020] [Accepted: 11/30/2020] [Indexed: 12/17/2022]
Abstract
The marine ecosystem has been known to be a significant source of novel enzymes. Esterase enzymes (EC 3.1.1.1) represent a diverse group of hydrolases that catalyze the cleavage and formation of ester bonds. Although esterases are widely distributed among marine organisms, only microbial esterases are of paramount industrial importance. This article discusses the importance of marine microbial esterases, their biochemical and kinetic properties, and their stability under extreme conditions. Since culture-dependent techniques provide limited insights into microbial diversity of the marine ecosystem, therefore, genomics and metagenomics approaches have widely been adopted in search of novel esterases. Additionally, the article also explains industrial applications of marine bacterial esterases particularly for the synthesis of optically pure substances, the preparation of enantiomerically pure drugs, the degradation of human-made plastics and organophosphorus compounds, degradation of the lipophilic components of the ink, and production of short-chain flavor esters.
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Affiliation(s)
- Noora Barzkar
- Department of Marine Biology, Faculty of Marine Science and Technology, University of Hormozgan, Bandar Abbas, 7931674576, Iran.
| | - Muhammad Sohail
- Department of Microbiology, University of Karachi, Karachi, 75270, Pakistan
| | - Saeid Tamadoni Jahromi
- Persian Gulf and Oman Sea Ecological Research Center, Iranian Fisheries Science Research Institute (IFSRI), Agricultural Research Education and Extension Organization (AREEO), Bandar Abbas, Iran
| | - Mohsen Gozari
- Persian Gulf and Oman Sea Ecological Research Center, Iranian Fisheries Science Research Institute (IFSRI), Agricultural Research Education and Extension Organization (AREEO), Bandar Abbas, Iran
| | - Sajjad Poormozaffar
- Persian Gulf Mollusks Research Station, Persian Gulf and Oman Sea Ecology Research Center, Agricultural Research Education and Extension Organization (AREEO), Iranian Fisheries Sciences Research Institute, Bandar-e-Lengeh, Iran
| | - Reza Nahavandi
- Animal Science Research Institute of Iran, Agricultural Research, Education and Extension Organization (AREEO), Karaj, Iran
| | - Mahmoud Hafezieh
- Iranian Fisheries Science Research Institute (ASRI), Agricultural Research, Education and Extension Organization (AREEO), Tehran, Iran
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6
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7
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Syntheses, structures and in vitro cytostatic activity of four novel homochiral organotin(IV) phosphonates. J Organomet Chem 2019. [DOI: 10.1016/j.jorganchem.2018.12.004] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
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8
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Nemtsov I, Mastai Y, Tischler YR, Aviv H. Chiral Purity of Crystals Using Low-Frequency Raman Spectroscopy. Chemphyschem 2018; 19:3116-3121. [PMID: 30178918 DOI: 10.1002/cphc.201800739] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/02/2018] [Indexed: 11/09/2022]
Abstract
The pharmaceutical industry is in need of new techniques to identify the chirality of solids due to regulatory and safety concerns regarding the biological activity of enantiomers. In this study, we present for the first time the application of low-frequency Raman spectroscopy as a new and sensitive method for analyzing the chiral purity of crystals. Using this method, we were able to identify small amounts, as low as 1 % w/w, of an enantiomer in racemic crystals. To demonstrate the capabilities of the method, we used a model system based on chiral crystals of enantiopure, racemic crystals and their mixtures in various ratios. We found that the low-frequency Raman spectra of racemic and enantiopure crystals are significantly different, reflecting the different hydrogen bond networks. Moreover, a comparison of the sensitivity of enantiomeric excess in chiral crystals to that of circular dichroism and X-ray diffraction measurements showed that low-frequency Raman attains high sensitivity comparable to chiral optical methods used for solutions. Overall, our proposed approach of using Raman spectroscopy for determining enantiomeric excess in crystals is simple, fast, and offers a high degree of chiral sensitivity.
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Affiliation(s)
- Irena Nemtsov
- Department of Chemistry and Bar-Ilan Institute for Nanotechnology and Advanced Materials (BINA), Bar Ilan University, Ramat Gan, 5290002, Israel
| | - Yitzhak Mastai
- Department of Chemistry and Bar-Ilan Institute for Nanotechnology and Advanced Materials (BINA), Bar Ilan University, Ramat Gan, 5290002, Israel
| | - Yaakov R Tischler
- Department of Chemistry and Bar-Ilan Institute for Nanotechnology and Advanced Materials (BINA), Bar Ilan University, Ramat Gan, 5290002, Israel
| | - Hagit Aviv
- Department of Chemistry and Bar-Ilan Institute for Nanotechnology and Advanced Materials (BINA), Bar Ilan University, Ramat Gan, 5290002, Israel
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9
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Dalal N, Buckner IS, Wildfong PLD. Experimental Determination and Theoretical Calculation of the Eutectic Composition of Cefuroxime Axetil Diastereomers. AAPS PharmSciTech 2017; 18:2570-2578. [PMID: 28229357 DOI: 10.1208/s12249-017-0739-8] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/08/2016] [Accepted: 02/02/2017] [Indexed: 11/30/2022] Open
Abstract
Cefuroxime axetil (CFA), an ester prodrug of cefuroxime exists as a pair of diastereoemers, namely isomer A and isomer B. To enable phase diagram construction, crystallization of the diastereomers of CFA from the commercially available amorphous drug substance was carried out. Isomer A was separated with a purity approaching 100% whereas the maximum purity of isomer B was 85% as confirmed by solution state proton NMR spectroscopy. The crystalline forms of isomer A and isomer B were confirmed as forms AI and BI, respectively, based on differential scanning calorimetry (DSC) analysis and powder X-ray diffraction. DSC analysis was used to observe the melting behavior of different diastereomer mixture compositions. The binary solid-liquid phase diagram for mixture compositions ranging from 0 to 85% w/w isomer B indicated the formation of a eutectic mixture having a melting temperature of 124.7 ± 0.4°C and a composition of 75% w/w (+/-5% wt.) isomer B. The eutectic composition was calculated using an index based on the van't Hoff equation for melting point depression and was found to be 75% isomer B and 25% isomer A. As CFA is present in commercial preparations as a mixture of diastereomers, the formation of a eutectic mixture between the diastereomers may impact the solubility and stability of the commercial product. Eutectic formation can be explained on the basis of the chemical similarity of diastereomers that favor miscibility in the liquid state.
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10
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Jang MG, Jang MD, Park JH. Doxycycline as a new chiral selector in capillary electrophoresis. J Chromatogr A 2017; 1508:176-181. [DOI: 10.1016/j.chroma.2017.06.019] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/13/2017] [Revised: 06/03/2017] [Accepted: 06/08/2017] [Indexed: 10/19/2022]
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11
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Zhang C, Matzger AJ. A Newly Discovered Racemic Compound of Pioglitazone Hydrochloride Is More Stable than the Commercial Conglomerate. CRYSTAL GROWTH & DESIGN 2017; 17:414-417. [PMID: 31537981 PMCID: PMC6752731 DOI: 10.1021/acs.cgd.6b01638] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/10/2023]
Abstract
A novel racemic compound of pioglitazone hydrochloride is discovered 17 years after the FDA approval of the conglomerate. The racemic compound shows a lower dissolution rate than the conglomerate in simulated gastric fluid at room temperature and is more thermodynamically stable as evidenced by solubility measurements. Slurry transformation of a mixture of the two forms converts fully to the racemic compound. This report highlights the necessity to thoroughly explore solid forms to access the most thermodynamically stable form of a pharmaceutical and contrasts the structural features of the two forms.
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Affiliation(s)
- Chengcheng Zhang
- Department of Chemistry, University of Michigan, 930 North University Avenue, Ann Arbor, Michigan 48109-1055, United States
| | - Adam J. Matzger
- Department of Chemistry, University of Michigan, 930 North University Avenue, Ann Arbor, Michigan 48109-1055, United States
- Macromolecular Science and Engineering Program, University of Michigan, 930 North University Avenue, Ann Arbor, Michigan 48109-1055, United States
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12
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Brandel C, Cartigny Y, Coquerel G, Ter Horst JH, Petit S. Prenucleation Self-Assembly and Chiral Discrimination Mechanisms during Solution Crystallisation of Racemic Diprophylline. Chemistry 2016; 22:16103-16112. [PMID: 27667660 DOI: 10.1002/chem.201602707] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/07/2016] [Indexed: 11/08/2022]
Abstract
The crystallisation behaviour of (RS)-diprophylline (DPL) in two different solvents is investigated to assess the incidence of solvated pre-associations on nucleation, crystal growth and chiral discrimination. In the solvated state, Raman spectroscopy shows that dimeric associations similar to those depicted in the crystalline solid solution (ssRII) predominate in isopropanol (IPA), which may account for the systematic spontaneous nucleation of this crystal form from this solvent. By contrast, spontaneous nucleation in DMF yields the stable racemic compound RI, consistently with the distinct features of the Raman spectrum collected in this solvent. A crystal growth study of ssRII in IPA reveals that the crystal habitus is impacted by the solution enantiomeric excess; this is explained by increased competition between homo- and heterochiral pre-associations. This is supported by a molecular modelling study on the enantiomeric selectivity of the DPL crystal lattices. The combination of assessment methods on solution chemistry, nucleation and chiral discrimination provides methodological tools from which the occurrence of solid solutions can be rationalised.
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Affiliation(s)
- Clément Brandel
- Normandi Université, Laboratoire SMS-EA3233, Université de Rouen, 76821, Mont Saint Aignan Cedex, France.
| | - Yohann Cartigny
- Normandi Université, Laboratoire SMS-EA3233, Université de Rouen, 76821, Mont Saint Aignan Cedex, France
| | - Gérard Coquerel
- Normandi Université, Laboratoire SMS-EA3233, Université de Rouen, 76821, Mont Saint Aignan Cedex, France
| | - Joop H Ter Horst
- University of Strathclyde, EPSRC Centre for Innovative, Manufacturing in Continuous Manufacturing and, Crystallisation (CMAC), Strathclyde Institute of Pharmacy, and Biomedical Sciences (SIPBS), Technology and Innovation Centre, 99 George Street, Glasgow, G1 1RD, UK
| | - Samuel Petit
- Normandi Université, Laboratoire SMS-EA3233, Université de Rouen, 76821, Mont Saint Aignan Cedex, France
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13
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Functional Characterization of a Marine Bacillus Esterase and its Utilization in the Stereo-Selective Production of D-Methyl Lactate. Appl Biochem Biotechnol 2016; 180:1467-1481. [PMID: 27364331 DOI: 10.1007/s12010-016-2180-y] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/25/2016] [Accepted: 06/22/2016] [Indexed: 10/21/2022]
Abstract
Chiral lactic acid and its ester derivatives are crucial building blocks and platforms in the generation of high value-added drugs, fine chemicals and functional materials. Optically pure D-lactic acid and its ester derivatives cannot be directly generated from fermentation and are quite expensive. Herein, we identified, heterologously expressed and functionally characterized one Bacillus esterase BSE01701 from the deep sea of the Indian Ocean. Esterase BSE01701 could enzymatically resolve inexpensive racemic methyl lactate and generate chiral D-methyl lactate. The enantiomeric excess of desired chiral D-methyl lactate and the substrate conversion could reach over 99 % and 60 %, respectively, after process optimization. Notably, the addition of 60 % (v/v) organic co-solvent heptane could greatly improve both the enantiomeric excess of D-methyl lactate and the conversion. BSE01701 was a very promising marine microbial esterase in the generation of chiral chemicals in industry.
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14
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Wu J, Liu F, Wang S, Wang H, Liu Q, Song X, Li J, Xu L, Tan W. Resolution of Rac-Bambuterol via Diastereoisomeric Salt Formation with o-Chloromandelic Acid and Differences in the Enantiomers' Pharmacodynamical Effects in Guinea Pigs and Beagles. Chirality 2016; 28:306-12. [PMID: 26969816 DOI: 10.1002/chir.22573] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/17/2015] [Revised: 12/09/2015] [Accepted: 12/11/2015] [Indexed: 11/06/2022]
Abstract
In this study an enantioseparation method for rac-bambuterol (5-(2-(tert-butylamino)-1-hydroxyethyl)-1,3-phenylene bis(dimethylcarbamate)) via diastereoisomeric salt formation with o-chloromandelic acid was developed. The enantiomeric excess (ee) values and chemical purities of the desired products were confirmed by high-performance liquid chromatography (HPLC) using chiral stationary phase and reverse-phase HPLC analyses, respectively. The ee values and the chemical purities both exceeded 99%. Animal experiments showed that (R)-bambuterol was a potent inhibitor for histamine-induced asthma reactions. (S)-bambuterol was ineffective in relaxing the airways. Both enantiomers increased heart rates in beagles. Therefore, replacing rac-bambuterol with (R)-bambuterol could be beneficial for asthma patients.
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Affiliation(s)
- Jie Wu
- School of Bioscience and Bioengineering, South China University of Technology; Pre-Incubator for Innovative Drug and Medicine, South China University of Technology; Guangdong Provincial Key Laboratory of Fermentation and Enzyme Engineering, South China University of Technology, Guangzhou, Guangdong, China
| | - Fei Liu
- School of Bioscience and Bioengineering, South China University of Technology; Pre-Incubator for Innovative Drug and Medicine, South China University of Technology; Guangdong Provincial Key Laboratory of Fermentation and Enzyme Engineering, South China University of Technology, Guangzhou, Guangdong, China
| | - Shanping Wang
- School of Bioscience and Bioengineering, South China University of Technology; Pre-Incubator for Innovative Drug and Medicine, South China University of Technology; Guangdong Provincial Key Laboratory of Fermentation and Enzyme Engineering, South China University of Technology, Guangzhou, Guangdong, China
| | - Hongjun Wang
- School of Bioscience and Bioengineering, South China University of Technology; Pre-Incubator for Innovative Drug and Medicine, South China University of Technology; Guangdong Provincial Key Laboratory of Fermentation and Enzyme Engineering, South China University of Technology, Guangzhou, Guangdong, China
| | - Qing Liu
- School of Bioscience and Bioengineering, South China University of Technology; Pre-Incubator for Innovative Drug and Medicine, South China University of Technology; Guangdong Provincial Key Laboratory of Fermentation and Enzyme Engineering, South China University of Technology, Guangzhou, Guangdong, China
| | - Xinghan Song
- School of Bioscience and Bioengineering, South China University of Technology; Pre-Incubator for Innovative Drug and Medicine, South China University of Technology; Guangdong Provincial Key Laboratory of Fermentation and Enzyme Engineering, South China University of Technology, Guangzhou, Guangdong, China
| | - Junxiao Li
- School of Bioscience and Bioengineering, South China University of Technology; Pre-Incubator for Innovative Drug and Medicine, South China University of Technology; Guangdong Provincial Key Laboratory of Fermentation and Enzyme Engineering, South China University of Technology, Guangzhou, Guangdong, China
| | - Ling Xu
- Keypharma Biomedical Inc., Songshan Lake Science & Technology Industry Park, Dongguan, Guangdong, China
| | - Wen Tan
- School of Bioscience and Bioengineering, South China University of Technology; Pre-Incubator for Innovative Drug and Medicine, South China University of Technology; Guangdong Provincial Key Laboratory of Fermentation and Enzyme Engineering, South China University of Technology, Guangzhou, Guangdong, China
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15
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Valencia I, Ávila-Torres Y, Barba-Behrens N, Garzón IL. Structural, vibrational, and electronic properties of an uncoordinated pseudoephedrine derivative and its mononuclear and trinuclear copper(II)-coordinated compounds: A combined theoretical and experimental study. J Mol Struct 2014. [DOI: 10.1016/j.molstruc.2014.08.020] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/24/2022]
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16
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Che QE, Quan P, Mu M, Zhang X, Zhao H, Zhang Y, You S, Xiao Y, Fang L. Enantioselective skin permeation of ibuprofen enantiomers: mechanistic insights from ATR-FTIR and CLSM studies based on synthetic enantiomers as naphthalimide fluorescent probes. Expert Opin Drug Deliv 2014; 11:1513-23. [DOI: 10.1517/17425247.2014.929661] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
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17
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Ahmed Hassan LE, Khadeer Ahamed MB, Abdul Majid AS, Iqbal MA, Al Suede FSR, Haque RA, Ismail Z, Ein OC, Majid AMSA. Crystal structure elucidation and anticancer studies of (-)-pseudosemiglabrin: a flavanone isolated from the aerial parts of Tephrosia apollinea. PLoS One 2014; 9:e90806. [PMID: 24608571 PMCID: PMC3946547 DOI: 10.1371/journal.pone.0090806] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/10/2013] [Accepted: 02/04/2014] [Indexed: 01/20/2023] Open
Abstract
Tephrosia apollinea is a perennial shrublet widely distributed in Africa and is known to have medicinal properties. The current study describes the bio-assay (cytotoxicity) guided isolation of (-)-pseudosemiglabrin from the aerial parts of T. apollinea. The structural and stereochemical features have been described using spectral and x-ray crystallographic techniques. The cytotoxicity of isolated compound was evaluated against nine cancer cell lines. In addition, human fibroblast was used as a model cell line for normal cells. The results showed that (-)-pseudosemiglabrin exhibited dose-dependent antiproliferative effect on most of the tested cancer cell lines. Selectively, the compound showed significant inhibitory effect on the proliferation of leukemia, prostate and breast cancer cell lines. Further studies revealed that, the compound exhibited proapoptotic phenomenon of cytotoxicity. Interestingly, the compound did not display toxicity against the normal human fibroblast. It can be concluded that (-)-pseudosemiglabrin is worthy for further investigation as a potential chemotherapeutic agent.
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Affiliation(s)
- Loiy Elsir Ahmed Hassan
- EMAN Research and Testing Laboratory, School of Pharmaceutical Sciences, Universiti Sains Malaysia, Penang, Malaysia
| | - Mohamed B. Khadeer Ahamed
- EMAN Research and Testing Laboratory, School of Pharmaceutical Sciences, Universiti Sains Malaysia, Penang, Malaysia
| | - Aman Shah Abdul Majid
- Advanced Medical and Dental Institute (IPPT), Universiti Sains Malaysia, Penang, Malaysia
| | | | - Fouad Saleih R. Al Suede
- EMAN Research and Testing Laboratory, School of Pharmaceutical Sciences, Universiti Sains Malaysia, Penang, Malaysia
| | - Rosenani A. Haque
- School of Chemical Sciences, Universiti Sains Malaysia, Penang, Malaysia
| | - Zhari Ismail
- EMAN Research and Testing Laboratory, School of Pharmaceutical Sciences, Universiti Sains Malaysia, Penang, Malaysia
| | - Oon Chern Ein
- Institute for Research in Molecular Medicine (INFORMM), Universiti Sains Malaysia, Penang, Malaysia
| | - Amin Malik Shah Abdul Majid
- EMAN Research and Testing Laboratory, School of Pharmaceutical Sciences, Universiti Sains Malaysia, Penang, Malaysia
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18
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Choobdari E, Fakhraian H, Peyrovi MH. Anion Effect on the Binary and Ternary Phase Diagrams of Chiral Medetomidine Salts and Conglomerate Crystal Formation. Chirality 2014; 26:183-8. [DOI: 10.1002/chir.22299] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/29/2013] [Revised: 12/03/2013] [Accepted: 12/11/2013] [Indexed: 12/13/2022]
Affiliation(s)
- Ebrahim Choobdari
- Department of Chemistry; Shahid Beheshti University; Evin Tehran Iran
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19
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Yuan X, Capomacchia AC. Influence of Physicochemical Properties on the In Vitro Skin Permeation of the Enantiomers, Racemate, and Eutectics of Ibuprofen for Enhanced Transdermal Drug Delivery. J Pharm Sci 2013; 102:1957-1969. [DOI: 10.1002/jps.23548] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/21/2012] [Revised: 03/12/2013] [Accepted: 03/26/2013] [Indexed: 11/08/2022]
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20
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The exploration of the reversed enantioselectivity of a chitosan functionalized cellulose acetate membranes in an electric field driven process. J Memb Sci 2012. [DOI: 10.1016/j.memsci.2011.11.002] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
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21
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22
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Berendt RT, Munson EJ. Effect of enantiomeric ratio and preparation method on proline crystal form. CrystEngComm 2012. [DOI: 10.1039/c2ce06445f] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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23
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Václavík J, Kačer P, Kuzma M, Červený L. Opportunities offered by chiral η⁶-arene/N-arylsulfonyl-diamine-RuII catalysts in the asymmetric transfer hydrogenation of ketones and imines. Molecules 2011; 16:5460-95. [PMID: 21712760 PMCID: PMC6264677 DOI: 10.3390/molecules16075460] [Citation(s) in RCA: 59] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/25/2011] [Revised: 06/14/2011] [Accepted: 06/17/2011] [Indexed: 11/22/2022] Open
Abstract
Methods for the asymmetric transfer hydrogenation (ATH) of ketones and imines are still being intensively studied and developed. Of foremost interest is the use of Noyori's [RuCl(η⁶-arene)(N-TsDPEN)] complexes in the presence of a hydrogen donor (i-PrOH, formic acid). These complexes have found numerous practical applications and have been extensively modified. The resulting derivatives have been heterogenized, used in ATH in water or ionic liquids and even some attempts have been made to approach the properties of biocatalysts. Therefore, an appropriate modification of the catalyst that suits the specific requirements for the reaction conditions is very often readily available. The mechanism of the reaction has also been explored to a great extent. Model substrates, acetophenone (a ketone) and 6,7-dimethoxy-1-methyl-3,4-dihydroisoquinoline (an imine), are both reduced by this Ru catalytic system with almost perfect selectivity. However, in each case the major product is a different enantiomer (S- for an alcohol, R- for an amine when the S,S-catalyst is used), which demanded an in-depth mechanistic investigation. Full-scale molecular modelling of this system enabled us to visualize the plausible 3D structures of the transition states, allowing the proposition of a viable explanation of previous experimental findings.
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Affiliation(s)
- Jiří Václavík
- Department of Organic Technology, Institute of Chemical Technology, Technická 5, CZ-166 28 Prague, Czech Republic
| | - Petr Kačer
- Department of Organic Technology, Institute of Chemical Technology, Technická 5, CZ-166 28 Prague, Czech Republic
| | - Marek Kuzma
- Laboratory of Molecular Structure Characterization, Institute of Microbiology, v.v.i., Academy of Sciences of the Czech Republic, Vídeňská 1083, CZ-142 20, Prague, Czech Republic
| | - Libor Červený
- Department of Organic Technology, Institute of Chemical Technology, Technická 5, CZ-166 28 Prague, Czech Republic
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24
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Kumar AP, Park JH. Azithromycin as a new chiral selector in capillary electrophoresis. J Chromatogr A 2011; 1218:1314-7. [DOI: 10.1016/j.chroma.2010.12.106] [Citation(s) in RCA: 37] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/09/2010] [Revised: 12/17/2010] [Accepted: 12/24/2010] [Indexed: 10/18/2022]
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25
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Chen X, Rao J, Wang J, Gooding JJ, Zou G, Zhang Q. A facile enantioseparation for amino acids enantiomers using β-cyclodextrins functionalized Fe3O4 nanospheres. Chem Commun (Camb) 2011; 47:10317-9. [DOI: 10.1039/c1cc13734d] [Citation(s) in RCA: 67] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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26
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Gou L, Robl S, Leonhard K, Lorenz H, Sordo M, Butka A, Kesselheim S, Wolff M, Seidel-Morgenstern A, Schaber K. A hybrid process for chiral separation of compound-forming systems. Chirality 2010; 23:118-27. [DOI: 10.1002/chir.20886] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/25/2010] [Accepted: 06/16/2010] [Indexed: 11/08/2022]
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27
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Zhou Z, Xiao Y, Hatton TA, Chung TS. Novel membrane processes for the enantiomeric resolution of tryptophan by selective permeation enhancements. AIChE J 2010. [DOI: 10.1002/aic.12336] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
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28
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Polenske D, Lorenz H, Seidel‐Morgenstern A. The binary phase diagram of propranolol hydrochloride and crystallization‐based enantioseparation. J Pharm Sci 2010; 99:1762-73. [DOI: 10.1002/jps.21943] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
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29
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Hammond R, Jeck S, Ma C, Pencheva K, Roberts K, Auffret T. An examination of binding motifs associated with inter-particle interactions between facetted nano-crystals of acetylsalicylic acid and ascorbic acid through the application of molecular grid-based search methods. J Pharm Sci 2009; 98:4589-602. [DOI: 10.1002/jps.21758] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
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30
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Effects of spacer arm length and benzoation on enantioseparation performance of β-cyclodextrin functionalized cellulose membranes. J Memb Sci 2009. [DOI: 10.1016/j.memsci.2009.04.015] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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31
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Xiao Y, Lim HM, Chung TS, Rajagopalan R. Acetylation of beta-cyclodextrin surface-functionalized cellulose dialysis membranes with enhanced chiral separation. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2007; 23:12990-12996. [PMID: 18020384 DOI: 10.1021/la7026384] [Citation(s) in RCA: 36] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/25/2023]
Abstract
The enhanced enantiomeric separation of racemic phenylalanine solution has been demonstrated by the membrane-based chiral resolution method using an acetylated beta-cyclodextrin-immobilized cellulose dialysis membrane. Beta-cyclodextrin (CD) was first immobilized onto the surface of commercial cellulose dialysis membranes, followed by the acetylation reaction through the treatment of the membranes with acetic anhydride to form the chiral selective acetylated beta-cyclodextrin-immobilized cellulose dialysis membrane. The acetylated CD-immobilized membrane exhibits enantioselectivity in the range of 1.26-1.33 depending on the acetylation time. The improvement in enantioselectivity after acetylation was mainly attributed to the better discrimination ability of acetylated CD and the decrease in membrane pore size. Molecular modeling simulations indicate that the acetylation of hydroxyl groups would result in a CD conformation with torus distortions and would create higher steric hindrance for penetrants. As a result, compared to the original CD, the acetylated CD may have less effective binding but better discrimination of enantiomers. The energy drop is only 3 kcal/mol between different enantiomers before and after the binding of phenylalanine with an unmodified CD. The energy drop increases to 10 kcal/mol if acetylated CD is employed as the chiral selector, showing stronger characteristics for chiral selection.
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Affiliation(s)
- Youchang Xiao
- Department of Chemical and Biomolecular Engineering and Singapore-MIT Alliance, National University of Singapore, 10 Kent Ridge Crescent, Singapore 119260
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32
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Kim JT, Kang SG, Woo JH, Lee JH, Jeong BC, Kim SJ. Screening and its potential application of lipolytic activity from a marine environment: characterization of a novel esterase from Yarrowia lipolytica CL180. Appl Microbiol Biotechnol 2006; 74:820-8. [PMID: 17119955 DOI: 10.1007/s00253-006-0727-5] [Citation(s) in RCA: 35] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/07/2006] [Revised: 10/16/2006] [Accepted: 10/17/2006] [Indexed: 10/23/2022]
Abstract
To develop an enantioselective lipase/esterase hydrolyzing racemic ofloxacin ester to levofloxacin, samples were collected from a variety of marine environments such as cold sea, hydrothermal vent area, sediment, tidal flat area, arctic sea, marine organisms, and so on. Microorganisms were isolated by plating on an enrichment medium with simultaneous detection of lipolytic activities and screened for the hydrolysis of ofloxacin ester. Three candidates among isolates were selected, and one of them, identified as Yarrowia lipolytica CL180, hydrolyzed preferentially S-enantiomer of racemic ofloxacin ester. The lipase/esterase gene (yli180) was cloned by screening a genomic library. The sequence analysis revealed an open reading frame consisting of 1,431 bp that encoded a protein of 476 amino acids with a molecular mass of 53 kDa. The yli180 gene was expressed in Escherichia coli and purified to homogeneity. The optimum activity of the recombinant protein (rYli180) occurred at pH 7.5 and 35 degrees C, respectively. rYli180 preferentially hydrolyzed p-nitrophenyl esters of fatty acids with short chain lengths of < or =10 carbon atoms. This study represents a novel esterase of type B1 carboxylesterase/lipase family from a marine isolate, showing a potential usage as a biocatalyst because of enantioselectivity toward racemic ofloxacin ester.
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Affiliation(s)
- Jun-Tae Kim
- Marine Biotechnology Center, Korea Ocean Research & Development Institute, Ansan, South Korea
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33
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Liu Y, Wang X, Wang JK, Ching CB. Structural characterization and enantioseparation of the chiral compound praziquantel. J Pharm Sci 2005; 93:3039-46. [PMID: 15514924 DOI: 10.1002/jps.20211] [Citation(s) in RCA: 30] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
In this study, we aimed to characterize the chiral compound type of a leading antischistosomal drug, praziquantel. The optically pure praziquantel enantiomers were recovered from the racemic mixture by enantiomeric separation, which was performed on preparative scale chromatography by using a novel beta-cyclodextrin type chiral column. The thermodynamic properties of praziquantel were determined from differential scanning calorimetry and the physical properties were studied by examining Fourier transform infrared spectroscopy and X-ray powder diffraction. Based on the differential scanning calorimetry data, a melting point binary phase diagram was constructed. A ternary solubility phase diagram of praziquantel in methanol was also determined at the temperature of 0 degrees C. All the experimental results support the conclusion that praziquantel is a racemic compound. The characterization of physical properties of praziquantel and the phase diagram are crucial for understanding the rationality for the successful resolution of praziquantel and also provide the basis for designing the strategy of separation and recovery of pure enantiomer.
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Affiliation(s)
- Yue Liu
- Chemical and Process Engineering Centre, 4 Engineering Drive 4, Engineering Block 5, Basement 08, National University of Singapore, Singapore, 117576.
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34
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Custelcean R, Gorbunova MG. Protonation-assisted spontaneous resolution: formation of a homochiral 2D interpenetrated hydrogen-bonded network from 4,4′-binicotinic acid under highly acidic conditions. CrystEngComm 2005. [DOI: 10.1039/b501901j] [Citation(s) in RCA: 17] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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35
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Perlovich GL, Kurkov SV, Kinchin AN, Bauer-Brandl A. Thermodynamics of solutions III: comparison of the solvation of (+)-naproxen with other NSAIDs. Eur J Pharm Biopharm 2004; 57:411-20. [PMID: 15019002 DOI: 10.1016/j.ejpb.2003.10.021] [Citation(s) in RCA: 187] [Impact Index Per Article: 9.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/23/2003] [Revised: 10/29/2003] [Accepted: 10/29/2003] [Indexed: 10/26/2022]
Abstract
Naproxen was studied by classical thermoanalytical methods, namely sublimation calorimetry, solution calorimetry and the solubility method. Temperature dependence of a saturated vapor pressure was obtained and the sublimation enthalpy, deltaHsub(0) and entropy, deltaSsub(0) and their relative fraction of the total process were calculated. These parameters yielded for naproxen were compared to the respective data of other naphthalene derivatives. The crystal lattice energy of naproxen was calculated by two force fields (Gavezzotti et al. and Mayo et al.) and compared to the experimental data. Contributions of different motifs of the naproxen molecule to the total packing energy were analyzed. The Gibbs energy of solvation as well as enthalpic and entropic terms thereof in aliphatic alcohols have been studied for naproxen, and compared to model substances and other non-steroid anti-inflammatory drugs (benzoic acid, diflunisal and flurbiprofen). The major driving force of the solvation process is the enthalpy. The respective contributions of the specific and the non-specific solvation interactions in terms of absolute and relative values have been investigated.
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Affiliation(s)
- German L Perlovich
- Institute of Solution Chemistry, Russian Academy of Sciences, Ivanovo, Russian Federation
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36
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Datta S, Grant DJW. Crystal structures of drugs: advances in determination, prediction and engineering. Nat Rev Drug Discov 2004; 3:42-57. [PMID: 14708020 DOI: 10.1038/nrd1280] [Citation(s) in RCA: 302] [Impact Index Per Article: 15.1] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Affiliation(s)
- Sharmistha Datta
- Department of Pharmaceutics, College of Pharmacy, University of Minnesota, Weaver-Densford Hall, 308 Harvard Street SE, Minneapolis, Minnesota 55455-0343, USA
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37
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Assimopoulou AN, Papageorgiou VP. Study on the enantiomeric ratio of the pharmaceutical substances alkannin and shikonin. Biomed Chromatogr 2004; 18:791-9. [PMID: 15386577 DOI: 10.1002/bmc.390] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
Abstract
The chiral pair alkannin and shikonin (A/S) are potent pharmaceutical substances with a wide spectrum of biological activity; their enantiomeric ratio does not influence the major biological activity studied hitherto. Nevertheless, in pharmaceutical development and approval of chiral drugs from the Health and Regulatory Authorities, full documentation of methods of analysis of enantiomeric drugs, is required in order to evaluate the enantiomeric purity of starting materials and final products and to control the stability of enantiomers in pharmaceutical formulations under several experimental conditions. In the present study, the enantiomeric ratio of A/S was determined in several commercial samples of alkannin and shikonin and also the proportion of A/S derivatives in several Alkanna root samples, which are all used as active ingredients in pharmaceuticals. Light and air proved not to influence the enantiomeric ratio of A/S on a shikonin commercial sample, and temperature also did not alter the A/S ratio on shikonin and alkannin commercial samples. Microencapsulation of alkannin and shikonin commercial samples in ethylcellulose microspheres and also molecular inclusion of a shikonin commercial sample in beta-hydroxypropyl-cyclodextrin, which are used as drug delivery systems, did not alter the A/S enantiomeric ratio.
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Affiliation(s)
- A N Assimopoulou
- Organic Chemistry Laboratory, Department of Chemical Engineering, Aristotle University of Thessaloniki, 541 24 Thessaloniki, Greece
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38
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Hong Lu Y, Bun Ching C. Physicochemical properties, binary and ternary phase diagrams of ketoprofen. Chirality 2004; 16:541-8. [PMID: 15290690 DOI: 10.1002/chir.20075] [Citation(s) in RCA: 17] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
Abstract
Compared to simulated moving bed (SMB) chromatography, fractional crystallization is a simple and economical method for enantioseparation. Therefore, the coupling of SMB chromatography and fractional crystallization is suggested for enantioseparation of racemic compounds. In this work, a nonsteroidal antiinflammatory drug, ketoprofen (Kp), was chosen to be studied. Kp was verified as a racemic compound by FTIR, PXRD, and thermodynamic calculations. To derive the condition where pure (S)-Kp could be crystallized from a solution, which was previously enantiomerically enriched, the binary melting phase diagram and the ternary solubility phase diagram in the mixed solvent of ethanol and water over a temperature range of 15-30 degrees C were obtained. From these phase diagrams the eutectic point was determined as 91.6% mole percent (S)-Kp from the binary phase diagram and 91% from the ternary phase diagram. The results may provide valuable experiment data for the possibility of coupling fractional crystallization with SMB for Kp separation.
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Affiliation(s)
- Ying Hong Lu
- Department of Chemical and Environmental Engineering, National University of Singapore, Singapore.
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39
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Misl'anová C, Hutta M. Role of biological matrices during the analysis of chiral drugs by liquid chromatography. J Chromatogr B Analyt Technol Biomed Life Sci 2003; 797:91-109. [PMID: 14630145 DOI: 10.1016/j.jchromb.2003.07.018] [Citation(s) in RCA: 34] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
Abstract
The review article covers advances of chiral drugs analysis by high-performance liquid chromatography (HPLC) methods achieved during last 10 years. Emphasis is given to various aspects of influence of biological matrix in pharmacodynamics, pharmacokinetics, HPLC analysis. Discussed is composition of main biological matrices from the point of view of potential interferences to above-mentioned fields of study. Beside typical analytical approaches to chiral recognition in HPLC, sample pretreatment and/or clean-up by conventional extraction procedures, column switching (CSW) techniques using restricted access materials (RAMs), microdialysis (MCD) is discussed. Measurement of unbound drug concentration and discussion of column maintenance and remedy is an additional source of information and field where knowledge on complex properties and interactions of biological matrix is usefully applicable.
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Affiliation(s)
- Csilla Misl'anová
- Institute of Preventive and Clinical Medicine, Limbová 14, SK-833 01 37 Bratislava, Slovak Republic.
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40
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Tolochko NK, Yadroitsev IA, Myal’dun AZ, Kuznetsov VA, Okhrimenko TM, York P. Optimization of the local crystallization processes of preparing chiral drugs in periodic crystallizers. CRYSTALLOGR REP+ 2003. [DOI: 10.1134/1.1627448] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
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41
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Zhang GGZ, Paspal SYL, Suryanarayanan R, Grant DJW. Racemic species of sodium ibuprofen: characterization and polymorphic relationships. J Pharm Sci 2003; 92:1356-66. [PMID: 12820140 DOI: 10.1002/jps.10393] [Citation(s) in RCA: 47] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
Racemic and homochiral sodium ibuprofen were characterized by thermal analysis and powder X-ray diffractometry. The melting point phase diagram was constructed and thermodynamic calculation was performed. In contrast to racemic ibuprofen, which is a racemic compound, racemic sodium ibuprofen forms both a racemic conglomerate (termed the gamma-form) as well as two polymorphic racemic compounds, alpha and beta, which are less stable monotropes. From the supercooled liquid, alpha and beta crystallized along with the original gamma-form. Forms alpha and beta are "enantiotropically related" with a transition temperature between 75 degrees and 113 degrees C, but can be considered to be metastable monotropes of the racemic conglomerate, the stable gamma-form.
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Affiliation(s)
- Geoff G Z Zhang
- Department of Pharmaceutics, College of Pharmacy, University of Minnesota, Weaver-Densford Hall, 308 Harvard Street Southeast, Minneapolis, MN 55455-0343, USA
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42
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Wang X, Wang XJ, Ching CB. Solubility, metastable zone width, and racemic characterization of propranolol hydrochloride. Chirality 2002; 14:318-24. [PMID: 11968072 DOI: 10.1002/chir.10049] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
Characterization of the racemic species, which can be a racemic compound, a racemic conglomerate, or a pseudoracemate (solid solution), is a prerequisite for the design of crystallization resolution processes. It is useful to determine the solid/liquid equilibrium solubility of the enantiomer mixtures for crystallization operation. For the beta-blocker drug propranolol hydrochloride, Gibbs free energy of formation of racemic compound and entropy of mixing of the (R)- and (S)- enantiomers in the liquid state for racemic conglomerate were calculated. The structural differences between (R, S)-propranolol hydrochloride and its (S)-enantiomer were further investigated by powder X-ray diffraction patterns, infrared spectra, and solid-state NMR spectra. The solubility and metastable zone width of (R, S)- propranolol hydrochloride in a mixed solvent of methanol and acetone were determined by cooling crystallization over the temperature range 3.5-42.5 degrees C. The ternary solubility diagram of (R)-, (S)-propranolol hydrochloride was constructed using the same mixed solvent. The diagram will be useful as a guide for choosing crystallization operation conditions to produce pure enantiomers.
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Affiliation(s)
- Xin Wang
- Department of Chemical and Environmental Engineering, National University of Singapore, Singapore.
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43
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Jane Li Z, Ojala WH, Grant DJ. Molecular Modeling Study Of Chiral Drug Crystals: Lattice Energy Calculations. J Pharm Sci 2001. [DOI: 10.1002/jps.1103] [Citation(s) in RCA: 47] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
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Luner PE, Kirsch LE, Majuru S, Oh E, Joshi AB, Wurster DE, Redmon MP. Preformulation studies on the S-isomer of oxybutynin hydrochloride, an Improved Chemical Entity (ICE). Drug Dev Ind Pharm 2001; 27:321-9. [PMID: 11411899 DOI: 10.1081/ddc-100103731] [Citation(s) in RCA: 17] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2022]
Abstract
(S)-Oxybutynin HCl (S-OXY) is a white crystalline solid powder with an acicular particle morphology. Differential scanning calorimetry (DSC) thermograms revealed one characteristic endotherm at 116.2 degrees C. On rescanning a sample heated to 120 degrees C, no thermal events were distinguished in the temperature range 25 degrees C to 150 degrees C. Weight loss curves determined by thermogravimetric analysis showed a continuous, gradual weight loss of about 0.15% over the temperature range 30 degrees C to 110 degrees C, followed by a change in slope and more rapid weight loss beginning at 150 degrees C. Observation by hot-stage microscopy confirmed the melting endotherm observed by DSC. Equilibrium moisture uptake studies indicated low water vapor uptake at low relative humidities (<52.8%). At relative humidities of 75.3% and 84.3%, S-OXY first deliquesced and then converted to a lower melting point crystal form. X-ray powder diffraction (XRPD) data supported the DSC findings. S-OXY underwent degradation by ester hydrolysis at alkaline pHs. The kinetics of this reaction were studied at 25 degrees C in carbonate-bicarbonate buffers. Observed rate constants of 0.008 h(-1) and 0.0552 h(-1) were determined at pH 9.69 and 10.25, respectively. The pKa of S-OXY was 7.75. The aqueous solubility of S-OXY was described as a function of pH and the free-base solubility. The mean partition coefficient log P was 3.33 using 1-octanol. The surface tensions of aqueous solutions of S-OXY decreased with increasing concentration, but no concentration-independent region was observed, indicating that S-OXY does notform micelles in aqueous solution. The dissolution rate of S-OXY from a compressed disk in 0.1 N HCl was rapid, whereas it was considerably slower at pH 7.4. Addition of 1% hexadecyltrimethylammonium bromide (CTAB) at pH 7.4 significantly improved the dissolution rate. S-OXY displayed very poor flow properties when compared to standard pharmaceutical excipients. XRPD results indicated that S-OXY exhibited a loss in crystallinity following ball milling. Hiestand tableting indices indicated that S-OXY has good bonding properties andforms strong compacts, but is likely to be susceptible to capping on ejection from the die. This indicated the needfor a plastically deformable excipient such as Avicel PH-101 in tablet formulations.
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Affiliation(s)
- P E Luner
- Pharmaceutics Division, College of Pharmacy, University of Iowa, Iowa City 52242, USA
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Chaimbault C, Bosc JJ, Leger JM, Negrier P, Capelle F, Jarry C. Physicochemical and crystallographic evidence for polymorphism of the racemic ethyl (2-chloromethyl-2,3-dihydro-5H-oxazolo [3, 2-a]pyrimidin-5-one)-6-carboxylate. J Pharm Sci 2000; 89:1496-504. [PMID: 11015694 DOI: 10.1002/1520-6017(200011)89:11<1496::aid-jps12>3.0.co;2-7] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
Abstract
The various crystalline forms of an original bicyclic compound [ethyl (2-chloromethyl-2,3-dihydro-5H-oxazolo[3, 2-a]pyrimidin-5-one)-6-carboxylate); EOC] have been obtained and characterized by powder and single-crystal X-ray diffraction, differential scanning calorimetry (DSC), and infrared (IR) and Raman spectroscopy. At 4 degrees C in methanol, a monoclinic racemate (form II) crystallized from the racemic mixture, whereas at 20 degrees C, an orthorhombic racemate (form I) was isolated in trichloroethylene. By increasing the temperature, a solid-solid transition from the stable form II to the stable form I was observed with a Guinier-Simon camera. A I --> II transformation was observed at ambient temperature by DSC.
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Affiliation(s)
- C Chaimbault
- Laboratoire de Chimie Physique et Minérale, Université Bordeaux II, 146 rue Léo Saignat, 33076 - Bordeaux, France
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Abstract
Crystalline characteristics of racemic, pure R and S enantiomers and physical mixtures of Ketoprofen (KET) have been studied by DSC and X-ray diffractometry. Aqueous solubilities were 182.6 +/- 9.1 microg/ml for racemic KET, 259.6 +/- 6.6 microg/ml for R-KET, and 304.3 +/- 2.7 microg/ml for S-KET. Matrix tablets made with racemic and physical mixtures of KET show stereoselective drug release, which is faster for S-KET than for R-KET. This effect is more marked when the chiral excipient hydroxypropylmethylcellulose (HPMC) is used in place of the achiral Eudragit RL. Stereoselectivity of release is also affected by the amount of KET. Similar results were obtained when another chiral drug with low solubility, Ricobendazole (RBZ), is used. Depending on the excipient and drug dosage, more or less marked stereoselective drug release is obtained in RBZ matrix tablet formulations.
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Affiliation(s)
- C Alvarez
- Departamento de Farmacia y Tecnología Farmacéutica, Universidad Complutense de Madrid, Plaza Ramón y Cajal, 28040 Madrid, Spain
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Kordikowski A, York P, Latham D. Resolution of ephedrine in supercritical CO(2): A novel technique for the separation of chiral drugs. J Pharm Sci 1999; 88:786-91. [PMID: 10430543 DOI: 10.1021/js980459f] [Citation(s) in RCA: 30] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
Racemic ephedrine has been resolved by diastereomeric salt formation with mandelic acid using supercritical CO(2) as precipitating agent. Crystallizations were performed using the Solution Enhanced Dispersion by Supercritical Fluids (SEDS) technique. Temperature was varied between 35 and 75 degrees C, and pressures ranged from 100 to 350 bar. Resolution, determined by chiral capillary electrophoresis, is described as a function of temperature and density of the supercritical fluid. A comparison of SEDS-produced material with a conventional resolution method shows that SEDS-crystallized material exhibits identical properties to conventionally crystallized material.
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Affiliation(s)
- A Kordikowski
- Drug Delivery Group, School of Pharmacy, University of Bradford, Bradford, West Yorkshire, BD7 1DP, UK.
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48
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Li ZJ, Zell MT, Munson EJ, Grant DJ. Characterization of racemic species of chiral drugs using thermal analysis, thermodynamic calculation, and structural studies. J Pharm Sci 1999; 88:337-46. [PMID: 10052993 DOI: 10.1021/js980205u] [Citation(s) in RCA: 95] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
The identification of the racemic species, as a racemic compound, a racemic conglomerate, or a racemic solid solution (pseudoracemate), is crucial for rationalizing the potential for resolution of racemates by crystallization. The melting points and enthalpies of fusion of a number of chiral drugs and their salts were measured by differential scanning calorimetry. Based on a thermodynamic cycle involving the solid and liquid phases of the enantiomers and racemic species, the enthalpy, entropy and Gibbs free energy of the racemic species were derived from the thermal data. The Gibbs free energy of formation, is always negative for a racemic compound, if it can exist, and the contribution from the entropy of mixing in the liquid state to the free energy of formation is the driving force for the process. For a racemic conglomerate, the entropy of mixing in the liquid state is close to the ideal value of R ln 2 (1.38 cal.mol-1. K-1). Pseudoracemates behave differently from the other two types of racemic species. When the melting points of the racemic species is about 30 K below that of the homochiral species, is approximately zero, indicating that the racemic compound and racemic conglomerate possess similar relative stabilities. The powder X-ray diffraction patterns and 13C solid-state nuclear magnetic resonance spectra are valuable for revealing structural differences between a racemic compound and a racemic conglomerate. Thermodynamic prediction, thermal analysis, and structural study are in excellent agreement for identifying the nature of the racemic species.
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Affiliation(s)
- Z J Li
- Department of Pharmaceutics, College of Pharmacy, University of Minnesota, Weaver-Densford Hall, 308 Harvard Street SE, Minneapolis, Minnesota 55455-0343, USA
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Caira MR, Zanol M, Peveri T, Gazzaniga A, Giordano F. Structural characterization of two polymorphic forms of piroxicam pivalate. J Pharm Sci 1998; 87:1608-14. [PMID: 10189275 DOI: 10.1021/js980059s] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
The crystal and molecular structures of two polymorphs of piroxicam pivalate are presented and discussed. A peculiarity of the high melting (154 degrees C) polymorph is the association of piroxicam pivalate molecules as centrosymmetric dimers by hydrogen bonding. Two centrosymmetrically related N-H...N hydrogen bonds maintain the dimer structure involving the amido nitrogen atom as donor and the pyridine nitrogen atom as acceptor. Molecular association of this type does not occur in the crystal structures of drugs belonging to the oxicam class of nonsteroidal antiinflammatory drugs. Two distinct conformations coexist in the crystal of the low melting polymorph (136 degrees C) with differing hydrogen bonding arrangements within domains of the crystallographically independent molecules. The occurrence of different molecular conformations (conformational polymorphism) associated with different hydrogen bonding schemes in discrete domains is an unusual structural feature. Structural data for the two polymorphs are also correlated with the relevant infrared spectra. Computer-generated X-ray powder diffraction patterns for the two polymorphs of piroxicam pivalate are in very good agreement with the experimental ones, thus confirming the validity of the single-crystal X-ray models.
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Affiliation(s)
- M R Caira
- Department of Chemistry, University of Cape Town, Rondebosch, South Africa
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Kommuru TR, Khan MA, Reddy IK. Racemate and enantiomers of ketoprofen: phase diagram, thermodynamic studies, skin permeability, and use of chiral permeation enhancers. J Pharm Sci 1998; 87:833-40. [PMID: 9649351 DOI: 10.1021/js9704644] [Citation(s) in RCA: 55] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/08/2023]
Abstract
The role of intrinsic and extrinsic factors on transport of a chiral drug through the skin was studied. Ketoprofen (KP) was chosen as a model chiral drug. A possible relationship between the melting characteristics and the flux values of S- and RS-KP was investigated. The potential use of chiral enhancers, menthol and linalool, was also investigated. Thermal analyses were carried out for individual enantiomers and the racemate of KP. The melting temperature of each enantiomer was 22 degreesC lower than that of the racemic compound. Peak temperatures from the melting endotherms were plotted as a function of enantiomeric composition to give the binary phase diagram. The phase diagram suggested the presence of a racemic compound, and it was verified by calculations of the liquidus curve in the dystectic region using reported methods. Powder X-ray diffraction studies also confirmed that the racemate of KP is a racemic compound. The permeability of individual enantiomers and the racemate of KP through mice skin was determined in vitro using side-by-side diffusion cells. Transfer of R- and S-KP from aqueous solutions of both the racemate and pure enantiomer showed no significant differences in the rates of permeation, indicating that the rate of transfer of KP across the mice skin from these solutions was independent of the stereochemistry of the drug. No evidence of racemization during the transfer process was observed. The permeation-enhancing ratio of linalool was higher, but not significant, than that of l-menthol. The predicted ratio of enantiomer to racemate flux through the skin by the MTMT concept (1. 97) is in close agreement with the experimentally determined ratio (1.79) across mouse skin.
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Affiliation(s)
- T R Kommuru
- Division of Basic Pharmaceutical Sciences, College of Pharmacy and Health Sciences, Northeast Louisiana University, Monroe, Louisiana 71209, USA
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