Stereochemical study of tolperisone, a muscle relaxant agent, by circular dichroism and ultraviolet spectroscopy.


:The stereochemistry of tolperisone, a chiral aryl-alkyl basic ketone was investigated by means of circular dichroism (CD) and ultraviolet (UV) spectroscopy. The unusually high optical activity of tolperisone hydrochloride in the n-->pi* region is interpreted by the presence of a chiral conformer in solution. For stereochemical reasons, the C = O group and the aromatic moiety lack coplanarity by forming an inherently dissymetric chromophore, of M helicity. Similar helicity prevails in the crystal phase, according to the solid-state CD spectrum of (-)-tolperisone HCl salt. The chirality rule proposed by Snatzke for nonplanar benzoyl chromophores predicts the absolute configuration of (-)-tolperisone hydrochloride to be R, in agreement with other alpha-methyl-beta-amino-ketones.






Zsila F,Hollósi M,Gergely A




Has Abstract


2000-11-01 00:00:00














  • Enantiopure 4-oxazolin-2-ones and 4-methylene-2-oxazolidinones as chiral building blocks in a divergent asymmetric synthesis of heterocycles.

    abstract::Enantiopure 3-((R)- and 3-((S)-1-phenylethyl)-4-oxazoline-2-ones were evaluated as chiral building blocks for the divergent construction of heterocycles with stereogenic quaternary centers. The N-(R)- or N-(S)-1-phenylethyl group of these compounds proved to be an efficient chiral auxiliary for the asymmetric inductio...


    pub_type: 杂志文章


    authors: Santoyo BM,González-Romero C,Zárate-Zárate D,Hernández-Benitez RI,Pelayo V,Barrera E,Escalante CH,Fuentes-Benites A,Martínez-Morales G,López J,Vázquez MA,Delgado F,Jiménez-Vázquez HA,Tamariz J

    更新日期:2019-09-01 00:00:00

  • Separation and determination of tetracycline hydrochloride in real water samples using binary small molecule alcohol-salt aqueous two-phase system coupled with high-performance liquid chromatography.

    abstract::An environmental and sensitive sample pretreatment method was established and combined with high-performance liquid chromatography (HPLC) for the analysis of tetracycline hydrochloride (TC) in feed water and lake water. One element small molecule alcohol-salt aqueous two-phase system (ATPS) cannot effectively adjust t...


    pub_type: 杂志文章


    authors: Guo DG,Ni L,Wang L,Shao L

    更新日期:2019-09-01 00:00:00

  • Implications of chirality and geometric isomerism in some psychoactive drugs and their metabolites.

    abstract::Many drugs contain a chiral centre, or such a centre is introduced during metabolism of the drug in man and in animals. If a single chiral centre is present, the drug will normally exist as a mixture of two enantiomers, of which one may have quite different pharmacologic and/or toxic effects than the other. Chiral dru...


    pub_type: 杂志文章,评审


    authors: Coutts RT,Baker GB

    更新日期:1989-01-01 00:00:00

  • Separation and quantitation of (R)- and (S)-atenolol in human plasma and urine using an alpha 1-AGP column.

    abstract::A method for the determination of (R)- and (S)-atenolol in human plasma and urine is described. The enantiomers of atenolol are extracted into dichloromethane containing 3% heptafluorobutanol followed by acetylation with acetic anhydride at 60 degrees C for 2 h. The acetylated enantiomers were separated on a chiral al...


    pub_type: 杂志文章


    authors: Enquist M,Hermansson J

    更新日期:1989-01-01 00:00:00

  • Gas chromatographic separation of saturated aliphatic hydrocarbon enantiomers on permethylated beta-cyclodextrin.

    abstract::Enantiomers of chiral aliphatic hydrocarbons are generally difficult to separate because they lack functional groups to be derivatized in order to generate diastereomers. The systematic and quantitative separation of a series of branched hydrocarbon enantiomers using a chiral cyclodextrin stationary phase and a cryost...


    pub_type: 杂志文章


    authors: Meierhenrich UJ,Nguyen MJ,Barbier B,Brack A,Thiemann WH

    更新日期:2003-01-01 00:00:00

  • Chiroptical properties of diamino carboxylic acids.

    abstract::Diamino carboxylic acids have recently come to the attention of scientists working in the field of early life and its development. These are the monomers of a hypothetic early form of genetic material, the so-called Peptide Nucleic Acid (PNA) (Nielson et al., Proc Natl Acad Sci USA 2000;97:3868-3871). Since all biopol...


    pub_type: 杂志文章


    authors: Bredehöft JH,Breme K,Meierhenrich UJ,Hoffmann SV,Thiemann WH

    更新日期:2007-07-01 00:00:00

  • Enantiomeric resolution and modeling of DL-alanine-DL-tryptophan dipeptide on amylose stationary phase.

    abstract::The enantiomeric resolution of DL-alanine-DL-tryptophan dipeptide is described on amylose stationary phase. The eluent used was CH3 OH─CH3 COONH4 (10mM)─CH3 CN (50: 40, 10) at 0.8-mL/min flow, 230-nm detection, 25-minute run time, and 25°C ± 1°C temperature. The chiral phase was amylose [AmyCoat RP (15 cm × 0.46 cm × ...


    pub_type: 杂志文章


    authors: Ali I,Khattab RA,Alothman ZA,Badjah AY,Alwarthan A

    更新日期:2018-04-01 00:00:00

  • Absolute configuration determination of chiral molecules in the solution state using vibrational circular dichroism.

    abstract::Advances in the measurement, calculation, and application of vibrational circular dichroism (VCD) for the determination of absolute configuration are described. The purpose of the review is to provide an up-to-date perspective on the capability of VCD to solve problems of absolute stereochemistry for chiral molecules ...


    pub_type: 杂志文章


    authors: Freedman TB,Cao X,Dukor RK,Nafie LA

    更新日期:2003-11-01 00:00:00

  • Stereoselective intramolecular cyclization to 4-(hydroxymethyl)-3-(1H-indolyl)oxazolidin-2-ones.

    abstract::A simple high-yield three-steps route to optically active 4-hydroxymethyl-3-(1H-indolyl)oxazolidin-2-ones from (S)-glycidol is described. The key intermediates (R)-oxiran-2-ylmethyl 1H-indol-4/-5-ylcarbamates are obtained in high yields from (S)-glycidol. These are readily transformed to oxazolidin-2-ones, very intere...


    pub_type: 杂志文章


    authors: Chiummiento L,Funicello M,Tramutola F

    更新日期:2012-04-01 00:00:00

  • Improved synthesis and pharmacologic activity of the enantiomers of a new benzofurane type antiarrhythmic compound.

    abstract::An improved synthesis of the enantiomers of the new benzofurane-type antiarrhythmic compound 1 is described, which makes use of the enantiomerically pure mbe-lactol. Thus, acylation of the benzofurane 4 with acetic anhydride and subsequent bromination gave the bromoacetyl-derivative 6, which, after reduction with LiAl...


    pub_type: 杂志文章


    authors: Ecker G,Fleischhacker W,Helml T,Noe CR,Scasny S,Lemmens-Gruber R,Studenik C,Marei H,Heistracher P

    更新日期:1994-01-01 00:00:00

  • Chirality and chiroptical properties of amyloid fibrils.

    abstract::Chirality of amyloid fibrils-linear beta-sheet-rich aggregates of misfolded protein chains-often manifests in morphological traits such as helical twist visible in atomic force microscopy and in chiroptical properties accessible to vibrational circular dichroism (VCD). According to recent studies the relationship betw...


    pub_type: 杂志文章,评审


    authors: Dzwolak W

    更新日期:2014-09-01 00:00:00

  • Online sample concentration in partial-filling chiral electrokinetic chromatography – mass spectrometry.

    abstract::The concentration sensitivity of a racemic drug (chlorpheniramine maleate) in chiral capillary electrophoresis with electrospray ionization – mass spectrometric detection was improved ~500-fold via stacking. Enantiomeric separation was achieved through the use of a neutral chiral pseudostationary phase (2-hydroxpropyl...


    pub_type: 杂志文章


    authors: Wuethrich A,Haddad PR,Quirino JP

    更新日期:2014-11-01 00:00:00

  • Separation and toxicity of salithion enantiomers.

    abstract::Enantioseletive toxicities of chiral pesticides have become an environmental concern recently. In this study, we evaluated the enantiomeric separation of salithion on a suite of commercial chiral columns and assessed the toxicity of enantiomers toward butyrylcholinesterase and Daphnia magna. Satisfactory separations o...


    pub_type: 杂志文章


    authors: Zhou S,Lin K,Li L,Jin M,Ye J,Liu W

    更新日期:2009-11-01 00:00:00

  • Three-Dimensional Chemical Structure Search Using the Conformational Code for Organic Molecules (CCOM) Program.

    abstract::Searching the 3D structural fragments of organic molecules is challenging because of structural differences between X-ray and theoretically calculated geometries and the conformational flexibility of substituents. The codification program called Conformational Code for Organic Molecules (CCOM) can be used to unambiguo...


    pub_type: 杂志文章


    authors: Izumi H,Nafie LA,Dukor RK

    更新日期:2016-05-01 00:00:00

  • Highly enantioselective HPLC separations using the covalently bonded macrocyclic antibiotic, ristocetin A, chiral stationary phase.

    abstract::The macrocyclic glycopeptide, ristocetin A, was covalently bonded to a silica gel support and evaluated as a liquid chromatographic (LC) chiral stationary phase (CSP). Over 230 racemates were resolved in either the reversed-phase mode, the normal-phase mode, or the polar-organic mode. The retention behavior and select...


    pub_type: 杂志文章


    authors: Ekborg-Ott KH,Liu Y,Armstrong DW

    更新日期:1998-01-01 00:00:00

  • Enantiopurity determination of the enantiomers of the triple reuptake inhibitor indatraline.

    abstract::The present study describes the development of two approaches for the determination of the enantiopurity of both enantiomers of indatraline. Initially, a method was developed using different chiral solvating agents (CSAs) for diastereomeric discrimination regarding signal separation in (1)H nuclear magnetic resonance ...


    pub_type: 杂志文章


    authors: Grimm SH,Allmendinger L,Höfner G,Wanner KT

    更新日期:2013-12-01 00:00:00

  • Stereoselective determination of metoprolol and its metabolite α-hydroxymetoprolol in plasma by LC-MS/MS: application to pharmacokinetics during pregnancy.

    abstract::Metoprolol is available for clinical use as a racemic mixture. The S-(-)-metoprolol enantiomer is the one expressing higher activity in the blockade of the β(1)-adrenergic receptor. The α-hydroxymetoprolol metabolite also has activity in the blockade of the β(1)-adrenergic receptor. The present study describes the dev...


    pub_type: 杂志文章


    authors: Antunes Nde J,Cavalli RC,Marques MP,Lanchote VL

    更新日期:2013-01-01 00:00:00

  • Channel-like crystal structure of cinchoninium L-O-phosphoserine salt dihydrate.

    abstract::Studies on the interactions between L-O- phosphoserine, as one of the simplest fragments of membrane components, and the Cinchona alkaloid cinchonine, in the crystalline state were performed. Cinchoninium L-O-phosposerine salt dihydrate (PhSerCin) crystallizes in a monoclinic crystal system, space group P2(1), with un...


    pub_type: 杂志文章


    authors: Wesełucha-Birczyńska A,Oleksyn BJ,Watroba J

    更新日期:2010-06-01 00:00:00

  • Helicity of perfluoroalkyl chains controlled by the self-assembly of the Ala-Ala dipeptides.

    abstract::Four Ala-Ala dipeptides with a perfluoroalkyl chain at the N-terminal were synthesized. They were able to self-assemble into helical nanofibers and/or twisted nanobelts in a mixture of DMSO/H2 O. The handedness of nanofibers and nanobelts was controlled by the chirality of the alanine at the N-terminal. The stacking h...


    pub_type: 杂志文章


    authors: Zhang L,Lin S,Tong Q,Li Y,Wang Y,Li Y,Li B,Yang Y

    更新日期:2019-11-01 00:00:00

  • Highly enantioselective asymmetric autocatalysis of 2-alkenyl- and 2-vinyl-5-pyrimidyl alkanols with significant amplification of enantiomeric excess.

    abstract::2-Alkenyl- and 2-vinyl-5-pyrimidyl alkanols are highly enantioselective asymmetric autocatalysts with significant amplification of enantiomeric excess in the enantioselective addition of diisopropylzinc to 2-alkenyl- and 2-vinylpyrimidine-5-carbaldehydes. Consecutive asymmetric autocatalysis starting from 7% ee increa...


    pub_type: 杂志文章


    authors: Sato I,Yanagi T,Soai K

    更新日期:2002-02-01 00:00:00

  • Comparison of mid-infrared Fourier transform vibrational circular dichroism measurements with single and dual polarization modulations.

    abstract::Fourier transform infrared vibrational circular dichroism (FTIR-VCD) measurements have gone through major advances in the last decade. A major thrust in these advances was to find ways that can minimize the VCD spectral artifacts and obtain the VCD signals at enhanced signal quality. However, all these advances are no...


    pub_type: 杂志文章


    authors: Polavarapu PL,Shanmugam G

    更新日期:2011-10-01 00:00:00

  • Chemoenzymatic and microbial dynamic kinetic resolutions.

    abstract::This review tracks a decade of dynamic kinetic resolution developments with a biocatalytic inclination using enzymatic/microbial means for the resolution part followed by the racemization reactions either by means of enzymatic or chemocatalyst. These fast developments are due to the ability of the biocatalysts to sign...


    pub_type: 杂志文章


    authors: Kamaruddin AH,Uzir MH,Aboul-Enein HY,Halim HN

    更新日期:2009-04-01 00:00:00

  • Role of latent heat in chiral symmetry breaking transition in the crystallization of 1,1'-binaphthyl.

    abstract::The influence of latent heat dissipated by the crystallization of 1,1'-binaphthyl in its supercooled molten state on the chiral symmetry breaking transition was investigated. Temperature change in the crystallization system was monitored by infrared thermocamera. Temperature rise due to the dissipation of latent heat ...


    pub_type: 杂志文章


    authors: Asakura K,Hayashi M,Osanai S

    更新日期:2003-03-01 00:00:00

  • Programmed assembly of rigid-rod beta-barrel pores: thermal inversion of chirality.

    abstract::The programmed assembly of p-octiphenyl rods carrying six complementary tripeptide strands was studied in the presence of bilayer membranes using circular dichroism (CD) spectroscopy. Thermal CD experiments demonstrated programmed assembly of anionic and cationic rods into supramolecules at low temperature that irreve...


    pub_type: 杂志文章


    authors: Sakai N,Matile S

    更新日期:2004-01-01 00:00:00

  • Enantioselective separation and degradation of the herbicide dichlorprop methyl in sediment.

    abstract::Chiral pesticides currently constitute about 50% of all pesticides dosage used in China, and this ratio is increasing as more complex structures are introduced. Dichlorprop methyl (DCPPM) is a chiral herbicide consisting of a pair of enantiomers. In this study, the enantiomeric separation of DCPPM was investigated by ...


    pub_type: 杂志文章


    authors: Ma Y,Xu C,Wen Y,Liu W

    更新日期:2009-04-01 00:00:00

  • Separation of amino acid enantiomers by micelle-enhanced ultrafiltration.

    abstract::A Micelle-enhanced ultrafiltration (MEUF) separation process was investigated that can potentially be used for large-scale enantioseparations. Copper(II)-amino acid derivatives dissolved in nonionic surfactant micelles were used as chiral selectors for the separation of dilute racemic amino acids solutions. For the al...


    pub_type: 杂志文章


    authors: De Bruin TJ,Marcelis AT,Zuilhof H,Rodenburg LM,Niederländer HA,Koudijs A,Overdevest PE,Van der Padt A,Sudhölter EJ

    更新日期:2000-08-01 00:00:00

  • In vitro stereoselective degradation of carprofen glucuronide by human serum albumin. Characterization of sites and reactive amino acids.

    abstract::Acyl glucuronides formed from carboxylic acids can undergo hydrolysis, acyl migration, and covalent binding to proteins. In buffers at physiological pH, the degradation of acylglucuronide of a chiral NSAID, carprofen, consisted mainly of acyl migration. Acidic pH reduced hydrolysis and acyl migration, thus stabilizing...


    pub_type: 杂志文章


    authors: Georges H,Presle N,Buronfosse T,Fournel-Gigleux S,Netter P,Magdalou J,Lapicque F

    更新日期:2000-02-01 00:00:00

  • Enantiomeric separation of β-blockers and tryptophan using heparin as stationary and pseudostationary phases in capillary electrophoresis.

    abstract::The separation methods of the enantiomers of two β-blockers and tryptophan were studied using capillary electrochromatography with heparin covalently as well as non-covalently, bonded onto the capillary inner wall as stationary phase and electrokinetic chromatography with heparin as pseudostationary phase. In the case...


    pub_type: 杂志文章


    authors: Liu Y,Sombra LL,Stege PW

    更新日期:2018-06-25 00:00:00

  • Synthesis, absolute configuration, and application of enantiopure trans-1-aminobenz[f]indan-2-ol.

    abstract::Both novel enantiopure trans-1-aminobenz[f]indan-2-ols (4) were obtained from the racemate by the diastereomeric salt formation with (+)- and (-)-dibenzoyltartaric acids (8), respectively, and the absolute configuration of the enantiomer 4 in the less-soluble diastereomeric salt of racemic 4 with (+)-8 was determined ...


    pub_type: 杂志文章


    authors: Kobayashi Y,Kinbara K,Sato M,Saigo K

    更新日期:2005-02-01 00:00:00

  • Synthesis and circular dichroism studies of N,N-bis(2-quinolylmethyl)amino acid Cu(II) complexes: determination of absolute configuration and enantiomeric excess by the exciton coupling method.

    abstract::We report a method to determine the absolute configuration of alpha-amino acids by exciton coupled circular dichroism (ECCD). Naturally occurring amino acids were successfully derivatized with 2-bromomethylquinoline. Complexation of these conformationally flexible ligands with Cu(II) salts yielded defined propeller-li...


    pub_type: 杂志文章


    authors: Holmes AE,Zahn S,Canary JW

    更新日期:2002-06-01 00:00:00