Log in

Relevant bibliographies by topics / Enantiomer separation / Journal articles

To see the other types of publications on this topic, follow the link: Enantiomer separation.

Journal articles on the topic 'Enantiomer separation'

Author: Grafiati

Published: 4 June 2021

Last updated: 9 February 2022

Create a spot-on reference in APA, MLA, Chicago, Harvard, and other styles

Select a source type:

Consult the top 50 journal articles for your research on the topic 'Enantiomer separation.'

Next to every source in the list of references, there is an 'Add to bibliography' button. Press on it, and we will generate automatically the bibliographic reference to the chosen work in the citation style you need: APA, MLA, Harvard, Chicago, Vancouver, etc.

You can also download the full text of the academic publication as pdf and read online its abstract whenever available in the metadata.

Browse journal articles on a wide variety of disciplines and organise your bibliography correctly.

1

Hocking, Martin B., and Aga Z.-Q. Khan. "Chromatographic enantiomer separation and circular dichroism (CD) spectra of three 4-endosubstituted-3,6-diphenyl-3,6-phenylphosphorylcyclohexenes." Canadian Journal of Chemistry 85, no. 9 (2007): 600–602. http://dx.doi.org/10.1139/v07-088.

Full text

Abstract:

Three enantiomeric pairs of Diels–Alder adducts of 2,5-diphenylphosphole-1-oxide have been resolved by elution of each of the enantiomers with 95% ethanol from a swollen microcrystalline triacetylcellulose stationary phase. The degree of separation achieved in each case was confirmed by comparing the absorbance maximum of the UV spectrum of each separated enantiomer with that of a similar concentration of the relevant racemic mixture. The circular dichroism (CD) spectrum of each of the separated enantiomers was recorded, and spectral parameters are listed.Key words: enantiomer separations, thr

APA, Harvard, Vancouver, ISO, and other styles

2

Wu, Xiuli, Yange Zhang, Wenzhen Li, et al. "A Validated LC Method for the Enantiomeric Separation of EAI045 on Chiral Stationary Phase." Journal of Chromatographic Science 58, no. 6 (2020): 562–68. http://dx.doi.org/10.1093/chromsci/bmz125.

Full text

Abstract:

Abstract A simple and accurate chiral liquid chromatographic method was developed for enantiomeric resolution and determination of 2-(5-fluoro-2-hydroxyphenyl)-2-(1-oxo-2,3-dihydro-1H-isoindol-2-yl)-N-(1,3-thiazol-2-yl)acetamide (EAI045). The enantiomers of EAI045 were baseline resolved on a Chiralpak AD-H (250 mm × 4.6 mm, 5 μm) column using a mobile phase system containing n-hexane: 2-propanol (75: 25 v/v) at a flow rate of 1 mL min−1 at 30°C. The eluted analytes were subsequently detected with an ultraviolet detector at 254 nm. The effects of organic modifiers and temperature on the enantio

APA, Harvard, Vancouver, ISO, and other styles

3

Suraj Koorpet R, Akshay N, Nishanth G, Chandan R S, and Anand Kumar Tengli. "A Review on Chiral Columns/Stationary Phases for HPLC." International Journal of Research in Pharmaceutical Sciences 11, no. 2 (2020): 2466–80. http://dx.doi.org/10.26452/ijrps.v11i2.2240.

Full text

Abstract:

The chiral separation of pharmaceutical molecules and their precursors is one of the important areas of application of HPLC in pharmaceutical analysis for obtaining enantiomerically pure drug. The latter procedures include the use of so-called chiral selectors to enantio-selectively recognise and isolate the enantiomer. The direct approaches, i.e. those which do not derivate the compound of interest before separation, are addressed in detail, since they are now the most common approaches. The role of stereochemistry in medicinal products is being given greater emphasis to medical practice. For

APA, Harvard, Vancouver, ISO, and other styles

4

Li, Zhi Wei, Xing Jia, Chun Mei Xu, Lei Liu, and De Cai Fu. "Chiral Separation of Amlodipine and its Enantiomer on a Molecularly Imprinted Polymer-Based Stationary Phase." Advanced Materials Research 706-708 (June 2013): 36–39. http://dx.doi.org/10.4028/www.scientific.net/amr.706-708.36.

Full text

Abstract:

A new chiral stationary phase for amlodipine (3-ethyl 5-methyl-2 -[(-2-(aminoethoxymethyl)-4-(2-chlorophenyl)-1,4-dihydro-6-methyl-3,5-pyridinedicarboxylate) based on a molecularly imprinted polymer has been prepared by radiation polymerization method and used for chromatographic separation of the chiral enantiomers. The effects on the separation of mobile phase and flow rate were investigated, and the optimum conditions for HPLC were shown to be: mobile phase, chloroform; flow rate, 0.3 ml min-1; at room temperature. The results has shown that the amlodipine-imprinted polymer was capable of r

APA, Harvard, Vancouver, ISO, and other styles

5

Zhang, Ping, Sheng Wang, Dongmei Shi, et al. "Direct Enantiomeric Separation and Determination of Hexythiazox Enantiomers in Environment and Vegetable by Reverse-Phase High-Performance Liquid Chromatography." International Journal of Environmental Research and Public Health 17, no. 10 (2020): 3453. http://dx.doi.org/10.3390/ijerph17103453.

Full text

Abstract:

In the present study, the direct enantiomeric separation of hexythiazox enantiomers on Lux cellulose-1, Lux cellulose-2, Lux cellulose-3, Lux cellulose-4, Lux amylose-1 and Chirapak IC chiral columns were carefully investigated by reverse-phase high-performance liquid chromatography (RP-HPLC). Acetonitrile/water and methanol/water were used as mobile phase at a flow rate of 0.8 mL·min−1. The effects of chiral stationary phase, temperature, thermodynamic parameters, mobile phase component and mobile phase ratio on hexythiazox enantiomers separation were fully evaluated. Hexythiazox enantiomers

APA, Harvard, Vancouver, ISO, and other styles

6

Kant, Ravi, Ramesh Babu Bodla, Rubina Bhutani, and Garima Kapoor. "Enantioselective Box Behenken Optimized HPLC-DAD Method for the Simultaneous Estimation of Alogliptin Enantiomorphs in Pharmaceutical For mulations and their Pharmacokinetic Study in Rat Plasma." Advanced Pharmaceutical Bulletin 9, no. 1 (2019): 147–58. http://dx.doi.org/10.15171/apb.2019.018.

Full text

Abstract:

Purpose: A stereoselective high performance liquid chromatographic analytical method withphotodiode array detector was developed and validated as per the International Conferenceon Harmonization (ICH) guidelines for the determination of alogliptin (ALO) enantiomers informulations and rat plasma.Methods: Enantiomeric separation was performed on a Phenomenex Lux Cellulose-2 chiralcolumn. Box-Behnken design was used to identify the optimum conditions of the threeindependent variables for the desired output responses.Results: The HPLC peaks of ALO enantiomers and the internal standard pioglitazone

APA, Harvard, Vancouver, ISO, and other styles

7

Fang, Ying Ying, Xiao Ling Zha, Hui Li, and Wei Fang Yu. "Determination of Henry Constants of Azelnidipine Enantiomers on Chiralpak AD Column at Different Temperatures." Advanced Materials Research 1078 (December 2014): 78–81. http://dx.doi.org/10.4028/www.scientific.net/amr.1078.78.

Full text

Abstract:

Simulated moving bed (SMB) chromatographic separation has become a highly promising method for chiral separation due to the less solvent consumption and efficient utilization of stationary phase. As reported, Azelnidipine exists two isomeric forms, it is necessary to product azelnidipine single enantiomer for medical safety and drug developmen. However, the separation of azelnidipine enantiomers on SMB is complex, requiring many operating parameters. And the SMB processes with temperature gradient (non-isotherm) mode may have significant advantages over the traditional isothermal mode. In this

APA, Harvard, Vancouver, ISO, and other styles

8

Lankhorst, Peter, Jozef van Rijn, and Alexander Duchateau. "One-Dimensional 13C NMR Is a Simple and Highly Quantitative Method for Enantiodiscrimination." Molecules 23, no. 7 (2018): 1785. http://dx.doi.org/10.3390/molecules23071785.

Full text

Abstract:

The discrimination of enantiomers of mandelonitrile by means of 1D 13C NMR and with the aid of the chiral solvating agent (S)-(+)-1-(9-anthryl)-2,2,2-trifluoroethanol (TFAE) is presented. 1H NMR fails for this specific compound because proton signals either overlap with the signals of the chiral solvating agent or do not show separation between the (S)-enantiomer and the (R)-enantiomer. The 13C NMR method is validated by preparing artificial mixtures of the (R)-enantiomer and the racemate, and it is shown that with only 4 mg of mandelonitrile a detection limit of the minor enantiomer of 0.5% i

APA, Harvard, Vancouver, ISO, and other styles

9

Gandhi, Karan, Umang Shah, and Sandip Patel. "Drug Stereochemistry: A Prodigy For Pharmacology and Drug Development." Current Drug Discovery Technologies 17, no. 5 (2020): 565–73. http://dx.doi.org/10.2174/1570163816666190502101803.

Full text

Abstract:

Stereochemistry has evinced the importance of many chiral drugs with respect to drug designing and development. A literature review was conducted for several chiral drugs involving pharmacokinetic and pharmacodynamic parameters of their enantiomers along with their uses in certain diseased conditions. This article mainly includes the pharmacological profile review of some chiral drugs and the aspects due to which the single enantiomer is of importance as compared to the racemic mixture of the drug. This was achieved by moderating the side effects or toxic effects; or by the potentiated activit

APA, Harvard, Vancouver, ISO, and other styles

10

Pisaneschi, Lin, Leonard, et al. "The 3S Enantiomer Drives Enolase Inhibitory Activity in SF2312 and Its Analogues." Molecules 24, no. 13 (2019): 2510. http://dx.doi.org/10.3390/molecules24132510.

Full text

Abstract:

We recently reported that SF2312 ((1,5-dihydroxy-2-oxopyrrolidin-3-yl)phosphonic acid), a phosphonate antibiotic with a previously unknown mode of action, is a potent inhibitor of the glycolytic enzyme, Enolase. SF2312 can only be synthesized as a racemic-diastereomeric mixture. However, co-crystal structures with Enolase 2 (ENO2) have consistently shown that only the (3S,5S)-enantiomer binds to the active site. The acidity of the alpha proton at C-3, which deprotonates under mildly alkaline conditions, results in racemization; thus while the separation of four enantiomeric intermediates was a

APA, Harvard, Vancouver, ISO, and other styles

11

Mostafa, Gamal A. E., Mohammed M. Hefnawy, and Abdulrahman El-Majed. "Separation and Determination of Clenbuterol by HPLC Using a Vancomycin Chiral Stationary Phase." Journal of AOAC INTERNATIONAL 92, no. 3 (2009): 824–29. http://dx.doi.org/10.1093/jaoac/92.3.824.

Full text

Abstract:

Abstract Enantiomers of clenbuterol were separated by a new HPLC method on a chiral column. Enantiomeric resolution was achieved on a vancomycyin macrocyclic antibiotic chiral stationary phase known as chirobiotic V with UV detection at 247 nm. The polar ionic mobile phase consisting of methanoltriethylamineglacial acetic acid (100 + 0.05 + 0.025, v/v/v), was used at a flow rate of 1.0 mL/min. The method was validated for linearity, accuracy, precision, and robustness. Standard linear calibration curves were established for the R-() and S-(+) enantiomers over the range of 0.220 g/mL, and an av

APA, Harvard, Vancouver, ISO, and other styles

12

León-González, María Eugenia, and Noelia Rosales-Conrado. "Enantioselective determination of ibuprofen residues by chiral liquid chromatography: a systematic study of enantiomeric transformation in surface water and sediments." Environmental Chemistry 13, no. 4 (2016): 656. http://dx.doi.org/10.1071/en15146.

Full text

Abstract:

Environmental context Ibuprofen, a common anti-inflammatory drug and one of many pharmaceuticals sold as a mixture of enantiomers, has recently been found in river and surface waters. There are, however, few analytical methods able to separate and accurately measure ibuprofen enantiomers in environmental matrices. This study reports a method for quantifying ibuprofen enantiomers in sediments and surface water, and applies it to shed light on the degradation and fate of the enantiomers in aquatic systems. Abstract The enantioselective composition of ibuprofen in sediments in contact with surfac

APA, Harvard, Vancouver, ISO, and other styles

13

Bystrická, Zuzana, and Jozef Lehotay. "In Vitro Investigation of D- and Lenantiomer Synergistic Efects of Some Amino Acids." Nova Biotechnologica et Chimica 15, no. 1 (2016): 47–54. http://dx.doi.org/10.1515/nbec-2016-0005.

Full text

Abstract:

Abstract D-amino acids can arise from endogenous microbial flora, from ingestion with the diet or from spontaneous racemization of L-amino acids during ageing. In this work, the behavior of methionine, homocysteine and cysteine enantiomers was investigated in human serum in vitro during 0-72 h at incubation temperature 37°C. The separation of enantiomers was realized in two dimensional on-line system (the connection of an achiral column Purospher RP-18 endcapped and a chiral column Chirobiotic TAG). This system allowed simultaneous monitoring all tested amino acids and their enantiomers. The p

APA, Harvard, Vancouver, ISO, and other styles

14

Senthilkumar, T., and S. K. Asha. "An easy ‘Filter-and-Separate’ method for enantioselective separation and chiral sensing of substrates using a biomimetic homochiral polymer." Chemical Communications 51, no. 43 (2015): 8931–34. http://dx.doi.org/10.1039/c5cc01532d.

Full text

Abstract:

A new homochiral polyfluorene appended with l-glutamic acid demonstrated successful heterogeneous enatioselective separation of a wide variety of enantiomers from their aqueous racemic mixtures by selective uptake of l-enantiomer into the polymer.

APA, Harvard, Vancouver, ISO, and other styles

15

Raikar, Prachi, and Gurupadayya Bannimath. "Recent Trends in Chiral Separation-A Collective Paradigm of Selected Chiral Impurities." Current Pharmaceutical Analysis 16, no. 5 (2020): 456–73. http://dx.doi.org/10.2174/1573412915666181219144507.

Full text

Abstract:

Chiral separation plays a very important role in the modern pharmaceutical analysis and will continue in upcoming years. Separation and identification of chiral impurities are indispensable. According to ICH guidelines, only the active enantiomer of the drug has to be marketed, so there is a focus on separation of the inactive enantiomer which acts as a chiral impurity. The impurities present in the enantiomers also pose various toxic adverse effects on bioavailability and efficacy, hence the need to separate these impurities will forever be trending. This review primarily focuses on the separ

APA, Harvard, Vancouver, ISO, and other styles

16

Berkecz, Róbert, Dániel Tanács, Antal Péter, and István Ilisz. "Enantioselective Liquid Chromatographic Separations Using Macrocyclic Glycopeptide-Based Chiral Selectors." Molecules 26, no. 11 (2021): 3380. http://dx.doi.org/10.3390/molecules26113380.

Full text

Abstract:

Numerous chemical compounds of high practical importance, such as drugs, fertilizers, and food additives are being commercialized as racemic mixtures, although in most cases only one of the isomers possesses the desirable properties. As our understanding of the biological actions of chiral compounds has improved, the investigation of the pharmacological and toxicological properties has become more and more important. Chirality has become a major issue in the pharmaceutical industry; therefore, there is a continuous demand to extend the available analytical methods for enantiomeric separations

APA, Harvard, Vancouver, ISO, and other styles

17

Šaman, David, Martina Wimmerová та Zdeněk Wimmer. "Synthesis and Structure Assignment of 2-(4-Methoxybenzyl)cyclohexyl β-D-Galactopyranoside Stereoisomers". Collection of Czechoslovak Chemical Communications 71, № 8 (2006): 1186–98. http://dx.doi.org/10.1135/cccc20061186.

Full text

Abstract:

Several promoters were used in the Koenigs-Knorr synthesis of the title alkyl β-D-galactopyranosides, both in their diastereoisomeric forms (5a/5b and 6a/6b), resulting from the synthesis performed with the respective racemic cis and trans isomers of 2-(4-methoxybenzyl)cyclohexan-1-ol, and in their enantiomerically pure forms 5a and 6a, starting only from the (1S,2S)- and (1S,2R)-enantiomers of 2-(4-methoxybenzyl)cyclohexan-1-ol. The aim of the study was to find convenient modification(s) of the Koenigs-Knorr synthesis of alkyl β-D-galactopyranosides from more hindered and more complex 2-subst

APA, Harvard, Vancouver, ISO, and other styles

18

García-Cansino, Laura, María Ángeles García, and María Luisa Marina. "Simultaneous Enantiomeric Separation of Carfentrazone-Ethyl Herbicide and Its Hydrolysis Metabolite Carfentrazone by Cyclodextrin Electrokinetic Chromatography. Analysis of Agrochemical Products and a Degradation Study." Molecules 26, no. 17 (2021): 5350. http://dx.doi.org/10.3390/molecules26175350.

Full text

Abstract:

The different activity and toxicity that the enantiomers of agrochemicals may have requires the development of stereoselective analytical methodologies enabling the individual determination of each enantiomer. The aim of this work was to develop the first Electrokinetic Chromatography methodology enabling the simultaneous enantiomeric separation of carfentrazone-ethyl herbicide and its hydrolysis metabolite carfentrazone. The use of an anionic cyclodextrin as chiral selector (captisol at 2.5% (w/v)) in a 25 mM acetate buffer, at a temperature of 30 °C, and an applied voltage (reverse polarity)

APA, Harvard, Vancouver, ISO, and other styles

19

Bai, Hui. "Research progress of chiral ligand exchange stationary phases in the enantiomer resolution." E3S Web of Conferences 271 (2021): 04020. http://dx.doi.org/10.1051/e3sconf/202127104020.

Full text

Abstract:

The structure of chiral drugs contains at least one asymmetric center. When the enantiomers act on the human body, they are recognized by chiral receptors and enzymes in vivo, which will show different physiological effects and even adverse reactions. Therefore, it is very important for the development of chiral pharmacy to obtain chiral enantiomers with a single configuration by racemic resolution. Some general impurities will be introduced in the production of chiral drugs, thus the detection of impurities is also a crucial step in the quality control of chiral medicines. The chiral ligand e

APA, Harvard, Vancouver, ISO, and other styles

20

Zhu, Jun, Hanfa Zou, Wei Shi, Jianzhong Rui, Jianyi Ni, and Yukui Zhang. "Enantiomer separation by CEC." Science in China Series B: Chemistry 42, no. 5 (1999): 511–19. http://dx.doi.org/10.1007/bf02874274.

Full text

APA, Harvard, Vancouver, ISO, and other styles

21

Zhao, Yuan, Xuecheng Zhu, Wei Jiang, Huilin Liu, and Baoguo Sun. "Chiral Recognition for Chromatography and Membrane-Based Separations: Recent Developments and Future Prospects." Molecules 26, no. 4 (2021): 1145. http://dx.doi.org/10.3390/molecules26041145.

Full text

Abstract:

With the rapid development of global industry and increasingly frequent product circulation, the separation and detection of chiral drugs/pesticides are becoming increasingly important. The chiral nature of substances can result in harm to the human body, and the selective endocrine-disrupting effect of drug enantiomers is caused by differential enantiospecific binding to receptors. This review is devoted to the specific recognition and resolution of chiral molecules by chromatography and membrane-based enantioseparation techniques. Chromatographic enantiomer separations with chiral stationary

APA, Harvard, Vancouver, ISO, and other styles

22

Mohammed, Mostafa S., Mohamed M. Hefnawy, Abdulrhman A. Al-Majed, et al. "Development and Validation of a Chiral Liquid Chromatographic Assay for Enantiomeric Separation and Quantification of Verapamil in Rat Plasma: Stereoselective Pharmacokinetic Application." Molecules 26, no. 7 (2021): 2091. http://dx.doi.org/10.3390/molecules26072091.

Full text

Abstract:

A novel, fast and sensitive enantioselective HPLC assay with a new core–shell isopropyl carbamate cyclofructan 6 (superficially porous particle, SPP) chiral column (LarihcShell-P, LSP) was developed and validated for the enantiomeric separation and quantification of verapamil (VER) in rat plasma. The polar organic mobile phase composed of acetonitrile/methanol/trifluoroacetic acid/triethylamine (98:2:0.05: 0.025, v/v/v/v) and a flow rate of 0.5 mL/min was applied. Fluorescence detection set at excitation/emission wavelengths 280/313 nm was used and the whole analysis process was within 3.5 min

APA, Harvard, Vancouver, ISO, and other styles

23

Li, Yan Liang, Zhong Zhen Liu, Yu Fen Huang, et al. "Biphasic Enantioselective Partitioning of R,S-Omeprazole Enantiomers Using Chiral Extraction." Advanced Materials Research 1030-1032 (September 2014): 2334–39. http://dx.doi.org/10.4028/www.scientific.net/amr.1030-1032.2334.

Full text

Abstract:

Enantioselective partitioning of racemic omeprazole enantiomers was studied using a biphasic recognition chiral extraction system. Hydrophilic hydroxypropyl-ڂ-cyclodextrin in aqueous phase and hydrophobic D-tartaric acid hexyl ester in organic phase as chiral selectors which preferentially recognize (R)-omeprazole enantiomer and (S)-omeprazole enantiomer, respectively. Different experimental variable parameters could affect the chiral extraction efficiency. The largest distribution coefficientskS,kRand separation factorځwere obtained at concentrations o f 0.1 mol/L HP-ڂ-CD and 0.2 mol/L D-tart

APA, Harvard, Vancouver, ISO, and other styles

24

Pragadheesh, VPPalayam S., Anju Yadav, Manju Singh, and Chandan S. Chanotiya. "Characterization of Volatile Components of Zingiber roseum Essential Oil Using Capillary GC on Modified Cyclodextrins." Natural Product Communications 8, no. 2 (2013): 1934578X1300800. http://dx.doi.org/10.1177/1934578x1300800223.

Full text

Abstract:

The essential oil from different parts of Zingiber roseum plants was extracted by hydrodistillation, and analyzed using enantio-GC, capillary-GC and GC-MS. Two chiral selectors, 6- tert-butyldimethylsilyl-2,3-diethyl-β-cyclodextrin (TBDE-β-CD), and 2,3,6-methyl-β-cyclodextrin (PM-β-CD) doped into 14% cyanopropylphenyl/ 86% dimethylpolysiloxane, and 35% diphenyl/ 65% dimethylpolysiloxane, respectively were compared in order to clarify the stereochemistry and enantioselectivity of terpenoids using chiral gas chromatography. The enantiomeric excess for (1R)-(+)-α-pinene, (1R)-(+)-β-pinene, and (R

APA, Harvard, Vancouver, ISO, and other styles

25

Pocrnić, Marijana, Martin Ansorge, Magda Dovhunová, Iva Habinovec, Eva Tesařová, and Nives Galić. "Chiral separation of beta-blockers by high-performance liquid chromatography and determination of bisoprolol enantiomers in surface waters." Archives of Industrial Hygiene and Toxicology 71, no. 1 (2020): 56–62. http://dx.doi.org/10.2478/aiht-2020-71-3318.

Full text

Abstract:

AbstractBeta-blockers are chiral compounds with enantiomers that have different bioactivity, which means that while one is active, the other can be inactive or even harmful. Due to their high consumption and incomplete degradation in waste water, they may reach surface waters and affect aquatic organisms. To address this issue we developed a chromatographic method suitable for determining beta-blocker enantiomers in surface waters. It was tested on five beta-blockers (acebutolol, atenolol, bisoprolol, labetalol and metoprolol) and validated on bisoprolol enantiomers. Good enantioseparation of

APA, Harvard, Vancouver, ISO, and other styles

26

Heydari, Rouhollah, та Mojtaba Shamsipur. "Rapid Enantiomeric Separation and Quantitation of Levetiracetam on α-Acid Glycoprotein (AGP) Chiral Stationary Phase by High-Performance Liquid Chromatography". Journal of AOAC INTERNATIONAL 98, № 6 (2015): 1529–34. http://dx.doi.org/10.5740/jaoacint.15-016.

Full text

Abstract:

Abstract A new, simple, and rapid chiral HPLC method was developed for enantioselective analysis of levetiracetam and its enantiomer [(R )-α-ethyl-2- oxo-pyrrolidine acetamide] in a pharmaceutical formulation and bulk material. Enantiomeric separation was achieved on a chiral-α1 -acid glycoprotein (AGP) column (150 × 4.0 mm, 5 μm) using an isocratic mobile phase of phosphate buffer (pH = 7) at a flow rate of 0.7 mL/min. The UV detector was set at 210 nm. Calibration curves were linear in the range of 1–100 μg/mL and 0.4–20 μg/mL for levetiracetam and the (R)-enantiomer, respectively. LOD and L

APA, Harvard, Vancouver, ISO, and other styles

27

Cholli, Ashok L., and Miu-Ling Lau. "Simultaneous Detection of Optical Isomers and the Separation of Overlapping Resonances in a 1H NMR Spectrum of (+/-)-2,2-Dimethyl-1-Phenyl-1-Propanol Using an NMR Shift Reagent." Applied Spectroscopy 43, no. 7 (1989): 1168–72. http://dx.doi.org/10.1366/0003702894203471.

Full text

Abstract:

The enantiomer separation and the spectral simplification of overlapped resonances in a high-resolution 1H NMR spectrum of a model compound have been successfully accomplished with the use of paramagnetic shift reagent. Both 1H and 13C NMR have been applied to determine the composition of a mixture containing optically active enantiomers of (+/-)-2,2-dimethyl-1-phenyl-1-propanol.

APA, Harvard, Vancouver, ISO, and other styles

28

Gumustas, Mehmet, Sibel A. Ozkan, and Bezhan Chankvetadze. "Analytical and Preparative Scale Separation of Enantiomers of Chiral Drugs by Chromatography and Related Methods." Current Medicinal Chemistry 25, no. 33 (2018): 4152–88. http://dx.doi.org/10.2174/0929867325666180129094955.

Full text

Abstract:

While the amino acids, enzymes and hormones are chiral, chirality plays significant role in the life of plants, animals, as well as the human being. Chirality of molecules is important in various industries, such as pharmaceutical, agricultural, food, electronics, etc. Chiral drugs may have different bioavailability, distribution, biotransformation and excretion, as well as quantitatively and/or qualitatively different pharmacological or toxic properties. Enantiomerically pure chiral drugs have been increasingly developed for the pharmaceutical market due to their superiority from the viewpoin

APA, Harvard, Vancouver, ISO, and other styles

29

Bui, Cuong Viet, Thomas Rosenau та Hubert Hettegger. "Polysaccharide- and β-Cyclodextrin-Based Chiral Selectors for Enantiomer Resolution: Recent Developments and Applications". Molecules 26, № 14 (2021): 4322. http://dx.doi.org/10.3390/molecules26144322.

Full text

Abstract:

Polysaccharides, oligosaccharides, and their derivatives, particularly of amylose, cellulose, chitosan, and β-cyclodextrin, are well-known chiral selectors (CSs) of chiral stationary phases (CSPs) in chromatography, because they can separate a wide range of enantiomers. Typically, such CSPs are prepared by physically coating, or chemically immobilizing the polysaccharide and β-cyclodextrin derivatives onto inert silica gel carriers as chromatographic support. Over the past few years, new chiral selectors have been introduced, and progressive methods to prepare CSPs have been exploited. Also, c

APA, Harvard, Vancouver, ISO, and other styles

30

Sun, Jiayi, Miyase Gözde Gündüz, Junyuan Zhang, Jia Yu, and Xingjie Guo. "Direct Enantiomeric Resolution of Seventeen Racemic 1,4-Dihydropyridine-Based Hexahydroquinoline Derivatives by HPLC." International Journal of Molecular Sciences 20, no. 10 (2019): 2513. http://dx.doi.org/10.3390/ijms20102513.

Full text

Abstract:

1,4-Dihydropyridine (DHP) scaffold holds an outstanding position with its versatile pharmacological properties among all heterocyclic compounds. Although most of the commercially available DHPs are marketed as a racemic mixture, the chiral center at C-4 can lead to even opposite pharmacological activities between the enantiomers. In the present study, enantioseparation of seventeen DHP structural analogues, consisting of either pharmacologically active or newly synthesized derivatives, (M2-4, MD5, HM2, HM10, CE5, N11, N10, N7, M11, MC6-8, MC13, MD23, and 42IIP) by high-performance liquid chrom

APA, Harvard, Vancouver, ISO, and other styles

31

Küsters, Ernst, and Willy Rahmen. "Allo-Verbindungen mit ungewöhnlichem Verhalten bei der Gaschromatographie an chiraler stationärer Phase / Allo-Compounds with Unusual Behaviour in Gas Chromatography Using Chiral Stationary Phase." Zeitschrift für Naturforschung B 43, no. 5 (1988): 619–22. http://dx.doi.org/10.1515/znb-1988-0522.

Full text

Abstract:

Abstract The Separation of the enantiomers of D,L-allo-threoninol, necessary in racemization studies of peptide hydrolysates, gave a surprising result with respect to the elution series of the antipodes. Contrary to the rule (L before D on Chirasil-L-Val) D-allo-threoninol is eluted before its mirror image. This behaviour can only be explained by the differing importance of the asymmetric centres contained in the molecule. As a result of this and taking into account the chromatographic behaviour of allo-compounds refined model concepts of enantiomer separation must be devel-oped in future.The

APA, Harvard, Vancouver, ISO, and other styles

32

Gao, Li Ping, Wen Juan Li, and Xin Ping Wang. "A Validated Chiral HPLC Method for the Enantiomeric Separation of Melphalan HCl." Advanced Materials Research 781-784 (September 2013): 993–98. http://dx.doi.org/10.4028/www.scientific.net/amr.781-784.993.

Full text

Abstract:

A new and accurate chiral HPLC method was developed for the determination of Melphalan HCl, L-Phenylalanine, 4-bis (2-chloroethyl) amino hydrochloride an anti-cancer chemotherapy drug and its potential impurity namely D-Phenylalanine, 4-bis (2-chloroethyl) amino hydrochloride ( D-enantiomer) in bulk substance. HPLC separation was carried out by reverse phase chromatography on Crownpak CR (+) (5μm, 4.0x150mm) with a mobile phase composed of perchloric acid (pH 4.0): methanol in the ratio of 90:10. Melphalan and its potential impurities were baseline resolved in the optimized method. The pH of p

APA, Harvard, Vancouver, ISO, and other styles

33

Chen, Fuxin, Xiaoxian Ma, Chuangqian Chen, et al. "A Validated Chiral-RP-UPLC-MS/MS Method for the Enantiomeric Detection of Rivaroxaban In vitro." Current Pharmaceutical Analysis 15, no. 4 (2019): 305–11. http://dx.doi.org/10.2174/1573412914666180409145403.

Full text

Abstract:

Background: Rivaroxaban is the first oral, selective direct FXa inhibitor with rapid onset of action and its biological toxicity may be related to the enantiomer. </P><P> Objective: The aim of the current study was to develop and validate a precise, accurate, and specific direct Chiral-RP-UPLC-MS/MS method for the enantiomeric separation and detection of rivaroxaban and its enantiomer. Methods: The present study screened various conditions of chromatographic and mass spectra, including chromatographic column model, flow velocity, phase ratio, column temperature, and collision energ

APA, Harvard, Vancouver, ISO, and other styles

34

RAMESH, CH, DHARMASOTH RAMA DEVI DEVI, M. N. B. SRINIVAS, S. RADHA KRISHNA, NAGARAJU RAJANA, and K. BASAVAIAH. "Development and Validation of RP-Chiral HPLC Method for Determination of (R)-Enantiomer Excess Content in Efavirenz." Asian Journal of Chemistry 32, no. 9 (2020): 2208–12. http://dx.doi.org/10.14233/ajchem.2020.22755.

Full text

Abstract:

simple, specific, linear, accurate and precise reverse phase chiral HPLC method was developed for the separation of efavirenz enantiomers by using the Lux Amylose-2 column containing amylose tris(5-chloro-2-methyl phenyl carbamate) as a stationary phase. The mobile phase consists of 0.1 % formic acid in water and acetonitrile (55:45, v/v). The flow rate was kept at 1.0 mL/min and the detection wavelength used 252 nm and the column temperature was set at 25 ºC. The limit of detection was 0.01 mg/mL and the limit of quantification was 0.04 mg/mL. The linearity calibration curve of (R)-enantiomer

APA, Harvard, Vancouver, ISO, and other styles

35

Mann, Lea, Markus Lang, Philipp Schulze та ін. "Racemization-free synthesis of Nα-2-thiophenoyl-phenylalanine-2-morpholinoanilide enantiomers and their antimycobacterial activity". Amino Acids 53, № 8 (2021): 1187–96. http://dx.doi.org/10.1007/s00726-021-03044-1.

Full text

Abstract:

AbstractNα-2-thiophenoyl-d-phenylalanine-2-morpholinoanilide (MMV688845, IUPAC: N-(1-((2-morpholinophenyl)amino)-1-oxo-3-phenylpropan-2-yl)thiophene-2-carboxamide) from the Pathogen Box® library (Medicines for Malaria Ventures, MMV) is a promising lead compound for antimycobacterial drug development. Two straightforward synthetic routes to the title compound starting from phenylalanine or its Boc-protected derivative are reported. Employing Boc-phenylalanine as starting material and the T3P® and PyBOP® amide coupling reagents enables racemization-free synthesis, avoiding the need for subsequen

APA, Harvard, Vancouver, ISO, and other styles

36

Zhang, Ping, Yuhan He, Sheng Wang, et al. "Chiral Separation and Determination of Etoxazole Enantiomers in Vegetables by Normal-Phase and Reverse-Phase High Performance Liquid Chromatography." Molecules 25, no. 14 (2020): 3134. http://dx.doi.org/10.3390/molecules25143134.

Full text

Abstract:

The chiral separation of etoxazole enantiomers on Lux Cellulose-1, Lux Cellulose-3, Chiralpak IC, and Chiralpak AD chiral columns was carefully investigated by normal-phase high performance liquid chromatography and reverse-phase high performance liquid chromatography (HPLC). Hexane/isopropanol, hexane/n-butanol, methanol/water, and acetonitrile/water were used as mobile phase at a flow rate of 0.8 mL/min. The effects of chiral stationary phase, mobile phase component, mobile phase ratio, and temperature on etoxazole separation were also studied. Etoxazole enantiomers were baseline separated o

APA, Harvard, Vancouver, ISO, and other styles

37

Aboul-Enein, Hassan Y. "Enantiomer Separation: Fundamentals and Practical Methods." Chirality 18, no. 9 (2006): 772. http://dx.doi.org/10.1002/chir.20306.

Full text

APA, Harvard, Vancouver, ISO, and other styles

38

Delgado, Beatriz, Eva Pérez, M. Carmen Santano, and Cristina Minguillón. "Enantiomer separation by counter-current chromatography." Journal of Chromatography A 1092, no. 1 (2005): 36–42. http://dx.doi.org/10.1016/j.chroma.2005.03.034.

Full text

APA, Harvard, Vancouver, ISO, and other styles

39

Grosenick, Heiko, Volker Schurig, Jeanne Costante, and André Collet. "Gas chromatographic enantiomer separation of bromochlorofluoromethane." Tetrahedron: Asymmetry 6, no. 1 (1995): 87–88. http://dx.doi.org/10.1016/0957-4166(94)00358-i.

Full text

APA, Harvard, Vancouver, ISO, and other styles

40

Burger, Stefan, Thomas Franke, Thomas Fraunholz, Ronald H. W. Hoppe, Malte A. Peter, and Achim Wixforth. "Numerical Simulation of Surface Acoustic Wave Actuated Separation of Rigid Enantiomers by the Fictitious Domain Lagrange Multiplier Method." Computational Methods in Applied Mathematics 15, no. 3 (2015): 247–58. http://dx.doi.org/10.1515/cmam-2015-0009.

Full text

Abstract:

AbstractEnantiomers are chiral objects which differ by their orientation and are thus referred to as left-handed and right-handed enantiomers. In applications they mostly occur as so-called racemic compounds consisting of approximately the same amount of left- and right-handed species which may have completely different properties. Hence, the separation of left- from right-handed enantiomers is an important issue. Conventional technologies are based on gas or high pressure liquid chromatography, capillary electrophoresis, or nuclear magnetic resonance, but typically they are slow and require c

APA, Harvard, Vancouver, ISO, and other styles

41

Rosenbaum, Jerrold F. "Conclusion: The Future of Single-Isomer Pharmacology." CNS Spectrums 7, S1 (2002): 55. http://dx.doi.org/10.1017/s1092852900028613.

Full text

Abstract:

Taken together, the articles gathered in this supplement underscore the major role in drug development that single-isomer science can play—a role that will undoubtedly take on a greater importance in the future. While the chirality of certain pharmacologically active molecules has been recognized for almost a century, it is only in recent years that drug synthesis and chiral separation techniques have advanced far enough to allow meaningful comparisons among enantiomers. Now that these methods are broadly available, the potential applications of single isomer drug development are considerable.

APA, Harvard, Vancouver, ISO, and other styles

42

Masdar, Non Daina, Abdul Hadi Mahmud, Mohd Tajudin Mohd Ali, et al. "Synthesis and Characterization of Modified Polydimethylsiloxane Nanomembrane for Chiral Separation." Advanced Materials Research 1105 (May 2015): 231–36. http://dx.doi.org/10.4028/www.scientific.net/amr.1105.231.

Full text

Abstract:

Polydimethylsiloxane-2-[2-tert-Butoxycarbonylamino-(1H-pyrazol-4-yl)-propionylamino] -3-phenyl-propanoic acid (PDMS-BCPA) is a newly developed stereo-specific membrane that interacts with S configuration of enantiomers as chiral recognition sites. In this study, realization of PDMS-BCPA nanomembrane was achieved via anodized aluminum oxide (AAO) template synthesis approach followed by the attachment of synthesized chiral selector (BCPA) using simple immersion method. The effect of surface modification and the attachment with chiral selector were investigated and characterized using Fourier Tra

APA, Harvard, Vancouver, ISO, and other styles

43

van der Ent, Ed M., Tom P. H. Thielen, Martien A. Cohen Stuart, Albert van der Padt, and Jos T. F. Keurentjes. "Electrodialysis System for Large-Scale Enantiomer Separation." Industrial & Engineering Chemistry Research 40, no. 25 (2001): 6021–27. http://dx.doi.org/10.1021/ie0103759.

Full text

APA, Harvard, Vancouver, ISO, and other styles

44

Smolková-Keulemansová, E. "Gas Chromatographic Enantiomer Separation with Modified Cyclodextrins." Journal of Chromatography A 623, no. 2 (1992): 408. http://dx.doi.org/10.1016/0021-9673(92)80386-9.

Full text

APA, Harvard, Vancouver, ISO, and other styles

45

Nishi, Hiroyuki. "Enantiomer separation of drugs by electrokinetic chromatography." Journal of Chromatography A 735, no. 1-2 (1996): 57–76. http://dx.doi.org/10.1016/0021-9673(95)01262-1.

Full text

APA, Harvard, Vancouver, ISO, and other styles

46

Lu, Yizhihao, Huacheng Zhang, Yinlong Zhu, Philip J. Marriott, and Huanting Wang. "Emerging Homochiral Porous Materials for Enantiomer Separation." Advanced Functional Materials 31, no. 25 (2021): 2101335. http://dx.doi.org/10.1002/adfm.202101335.

Full text

APA, Harvard, Vancouver, ISO, and other styles

47

Alvira, Elena. "Molecular Simulation of the Separation of Isoleucine Enantiomers by β-Cyclodextrin". Molecules 24, № 6 (2019): 1021. http://dx.doi.org/10.3390/molecules24061021.

Full text

Abstract:

Molecular mechanics and dynamics simulations were carried out to study the capacity of isoleucine enantiomers to form inclusion complexes with β–cyclodextrin, and to be discriminated by this chiral compound, in vacuo and with different solvents. Solvents were characterized not only by the value of dielectric constant ε in the Coulombic interaction energy, but also by the neutral and zwitterion configurations of isoleucine. Whereas the discrimination between the enantiomers for ε ≤ 2 is due to the electrostatic contribution, these differences are mainly due to the Lennard-Jones potential for ε

APA, Harvard, Vancouver, ISO, and other styles

48

Bosits, Miklós Hunor, Emese Pálovics, János Madarász, and Elemér Fogassy. "New Discoveries in Enantiomeric Separation of Racemic Tofisopam." Journal of Chemistry 2019 (April 7, 2019): 1–10. http://dx.doi.org/10.1155/2019/4980792.

Full text

Abstract:

Resolution process of tofisopam has been re-evaluated now based on our new investigations. Originally, it was carried out in the water-chloroform system, where the intermediate salt of high diastereomeric excess was described as (R)-TOF·(R,R)-DBTA·(H2O)3. Opposed to previous assumptions, we have actually found that a different solvate composition, (R)-TOF‐(R,R)-DBTA-CHCl3, forms with chloroform, in which molecules of CHCl3 are captured and held with different strengths. Moreover, resolution of TOF with (R,R)-DBTA is possible (and favourable) in water-free solvent and solvent mixture. However,

APA, Harvard, Vancouver, ISO, and other styles

49

Li, Zhao-Yang, Zhi-Chao Zhang, Qi-Lin Zhou, Qing-Min Wang, Ru-Yu Gao, and Qin-Sun Wang. "Stereo- and Enantioselective Determination of Pesticides in Soil by Using Achiral and Chiral Liquid Chromatography in Combination with Matrix Solid-Phase Dispersion." Journal of AOAC INTERNATIONAL 86, no. 3 (2003): 521–28. http://dx.doi.org/10.1093/jaoac/86.3.521.

Full text

Abstract:

Abstract The separation of enantiomers and diastereomers of 8 commonly used pesticides was investigated by liquid chromatography (LC) using a Chiralcel OD column (cellulose tris-3,5-dimethylphenyl-carbamate as the chiral stationary phase) and a Pirkle-type Chirex 3020 column (urea derivative from the reaction of (R)-1-(α-naphthyl)ethylamine with (S)-tert-leucine, chemically bonded to 3-aminopropylsilanized silica as the chiral stationary phase). The pesticides studied included one organophosphorus insecticide (phenthoate), 3 triazole fungicides (uniconazole, diniconazole, and propiconazole), a

APA, Harvard, Vancouver, ISO, and other styles

50

Banerjee-Ghosh, Koyel, Oren Ben Dor, Francesco Tassinari, et al. "Separation of enantiomers by their enantiospecific interaction with achiral magnetic substrates." Science 360, no. 6395 (2018): 1331–34. http://dx.doi.org/10.1126/science.aar4265.

Full text

Abstract:

It is commonly assumed that recognition and discrimination of chirality, both in nature and in artificial systems, depend solely on spatial effects. However, recent studies have suggested that charge redistribution in chiral molecules manifests an enantiospecific preference in electron spin orientation. We therefore reasoned that the induced spin polarization may affect enantiorecognition through exchange interactions. Here we show experimentally that the interaction of chiral molecules with a perpendicularly magnetized substrate is enantiospecific. Thus, one enantiomer adsorbs preferentially

APA, Harvard, Vancouver, ISO, and other styles

We offer discounts on all premium plans for authors whose works are included in thematic literature selections. Contact us to get a unique promo code!