Improving enantiomeric resolutions by avoiding peak distortion effects in on-line coupled liquid chromatography to gas chromatography.

abstract：:[3β,5β,7α,12α]-3-(4-t-Butylbenzoilamine)-7,12-dihydroxycholan-24-oic acid was synthesized and recrystallized from chlorobenzene and acetone. Orthorhombic P2(1)2(1)2(1) and monoclinic P2(1) crystals were obtained, respectively, and both crystals include solvent and water molecules with a 1:1:1 stoichiometry. In the sec...

journal_title：Chirality

authors： Meijide F,Trillo JV,Soto VH,Jover A,Tato JV

更新日期：2011-11-01 00:00:00

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...

journal_title：Chirality

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

更新日期：1998-01-01 00:00:00

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...

journal_title：Chirality

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

更新日期：2013-01-01 00:00:00

abstract：:A variety of reactions can be categorized under the global concept of the "interconversion of stereoisomers." Thus, racemization or epimerization can result from inversion of labile chiral centers. From the examples available, some predictive rules are suggested for a chiral center of the type R"R'RC-H undergoing base...

journal_title：Chirality

authors： Testa B,Carrupt PA,Gal J

更新日期：1993-01-01 00:00:00

abstract：:The size, sign, and profile of induced circular dichroism (CD) features in the Soret region are reliable indicators of the binding modes of porphyrins and metalloporphyrins to DNA. Porphyrins shown (using such CD criteria) to be intercalators in monodispersed DNA duplexes prove extremely useful for the detection and c...

journal_title：Chirality

authors： Pasternack RF

更新日期：2003-05-05 00:00:00

abstract：:We have developed an improved circular dichroism (CD) and linear dichroism (LD) simultaneous measurement system for the vacuum ultraviolet (VUV) region by polarization modulation techniques using a four-period Onuki-type crossed undulator as a polarized light source. The system has been constructed at the VUV beamline...

journal_title：Chirality

authors： Tanaka M,Yagi-Watanabe K,Yamada T,Kaneko F,Nakagawa K

更新日期：2006-02-01 00:00:00

abstract：:Vibrational circular dichroism (VCD) spectra of (+)-alpha-pinene solutions in carbon tetrachloride have been measured in the range of volume fractions 5-100% (v/v) in the mid-infrared region. The concentration dependence measured was statistically analyzed with the aim of obtaining a reliable correlation between the V...

journal_title：Chirality

authors： Urbanova M,Setnicka V V,Volka K

更新日期：2000-05-01 00:00:00

abstract：:Hornet silks adopt a variety of morphology such as fibers, sponge, films, and gels depending on the preparation methods. We have studied the conformation change of hornet silk proteins (Vespa mandarina) as regenerated films, using chiroptical spectrophotometer universal chiroptical spectrophotometer 1, which can measu...

journal_title：Chirality

authors： Kuroda R,Kameda T

更新日期：2018-05-01 00:00:00

abstract：:A comparison of the enantiomeric resolution of (+/-)-threo-methylphenidate (MPH) (Ritalin) was achieved on different polysaccharide based chiral stationary phases. The mobile phase used was hexane-ethanol-methanol-trifluoroacetic acid (480:9.75:9.75:0.5, v/v/v/v). Benzoic acid and phenol were used as the mobile phase ...

journal_title：Chirality

authors： Aboul-Enein HY,Ali I

更新日期：2002-01-01 00:00:00

abstract：:(+/-)-Pantoprazole ((+/-)-PAN), (+/-)-5-(difluoromethoxy)-2-[[3.4-dimethoxy-2-pyridinyl)methyl]sul finyl]- 1H-benzimidazole) is a chiral sulfoxide that is used clinically as a racemic mixture. The disposition kinetics of (+)-PAN and (-)-PAN given separately has been studied in rats. Serum levels of (+)- and (-)-PAN an...

journal_title：Chirality

authors： Masubuchi N,Yamazaki H,Tanaka M

更新日期：1998-01-01 00:00:00

abstract：:In order to cope with the increasing number of publications on the separation of enantiomers by chromatography on a chiral stationary phase, the graphical molecular database CHIRBASE was created. In the present state, the database package covers information (structural, bibliographic, and chromatographic data) on liqu...

journal_title：Chirality

authors： Koppenhoefer B,Nothdurft A,Pierrot-Sanders J,Piras P,Popescu C,Roussel C,Stiebler M,Trettin U

更新日期：1993-01-01 00:00:00

abstract：:A chiral liquid chromatography/mass spectrometry (LC/MS) bioanalytical procedure has been developed for the analysis of the antimalaric agent Fenozan B07 in dog plasma. Normal-phase chromatography involving a phenylcarbamate derivative of cellulose coated on silica gel as the chiral stationary phase was used to resolv...

journal_title：Chirality

authors： Maraschiello C,Vilageliu J,Dorronsoro I,Martinez A,Floriano P,Gómez-Acebo E

更新日期：2006-05-15 00:00:00

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...

journal_title：Chirality

authors： Dzwolak W

更新日期：2014-09-01 00:00:00

abstract：:The chiral discrimination ability of two recently prepared chiral stationary phases (CSP 1 and CSP 2), based on a leucine derived chiral selector, was tested for the enantiomers of dihydropyrimidone (DHPM) derivatives and compared with the commercially available Hyun-leucine CSP 3 and classical Pirkle-leucine CSP 4. B...

journal_title：Chirality

authors： Forjan DM,Gazić I,Vinković V

更新日期：2007-06-01 00:00:00

abstract：:Kynurenic acid (KYNA), an endogenous antagonist of N-methyl-D-aspartate and α(7) nicotinic acetylcholine receptors, is one of the L-tryptophan (Trp) metabolites. To compare the level of KYNA produced in the striatum of rats after independent administration of L-Trp and D-Trp, rats were intraperitoneally administered L...

journal_title：Chirality

authors： Ishii K,Iizuka H,Ogaya T,Song Z,Fukushima T

更新日期：2011-01-01 00:00:00

abstract：:Two diastereomeric cationic surfactants derived from L-proline, in which the second chiral center is a quaternary nitrogen, have been separated and fully characterized. The recognition properties of the aggregates formed by the two diastereomeric surfactants have been investigated by circular dichroism and (1)H NMR th...

journal_title：Chirality

authors： Borocci S,Ceccacci F,Galantini L,Mancini G,Monti D,Scipioni A,Venanzi M

更新日期：2003-05-15 00:00:00

abstract：:Flurbiprofen is a kind of nonsteroidal anti-inflammatory drug, which has been widely used in clinic for treatment of rheumatoid arthritis and osteoarthritis. It has been reported that S-flurbiprofen shows good performance on clinic anti-inflammatory treatment, while R-enantiomer almost has no pharmacological activitie...

journal_title：Chirality

authors： Cui X,Ding Q,Shan RN,He CH,Wu KJ

更新日期：2019-06-01 00:00:00

abstract：:This study focused on the chiral characteristics of methamphetamine seizures in Shanghai for inferring the synthetic pathways of drugs. Capillary electrophoresis coupled to time-of-flight mass spectrometry was used for simultaneous chiral separation of amphetamine-type stimulants and ephedrine, including S(+)-amphetam...

journal_title：Chirality

authors： Cui X,Liang C,Gong F,Wang R,Ni C,Wu Y,Chen G,Zhang Y

更新日期：2018-09-01 00:00:00

abstract：:Massarigenin A (1) and papyracillic acids A (2) and B (3) were isolated from the endophytic fungus Microsphaeropsis sp. Their structures were elucidated by multidimensional nuclear magnetic resonance spectroscopy; the structure of massarigenin A (1) was also confirmed by X-ray crystallography. The absolute configurati...

journal_title：Chirality

authors： Hussain H,Ahmed I,Schulz B,Draeger S,Flörke U,Pescitelli G,Krohn K

更新日期：2011-09-01 00:00:00

abstract：:Chiral fungicide prothioconazole has a wide range of antifungal spectrum; however, little research has been conducted to evaluate prothioconazole on an enantiomeric level. Five target pathogens and three common aquatic organisms were tested for the enantioselective bioactivity and toxicity of prothioconazole in this w...

journal_title：Chirality

authors： Zhai W,Zhang L,Cui J,Wei Y,Wang P,Liu D,Zhou Z

更新日期：2019-06-01 00:00:00

abstract：:In this computational study, we illustrate a method for computing phosphorescence and circularly polarized phosphorescence spectra of molecular systems, which takes into account vibronic effects including both Franck-Condon and Herzberg-Teller contributions. The singlet and triplet states involved in the phosphorescen...

journal_title：Chirality

authors： Egidi F,Fusè M,Baiardi A,Bloino J,Li X,Barone V

更新日期：2018-07-01 00:00:00

abstract：:(R)-(+) and (S)-(-)-1-phenylethylamine have been shown to promote highly diastereoselective and complementary enantioselective formal [3 + 2]carbocyclization reactions between 2,3-butanedione and conjugated nitroalkenes with formation of enantiomerically rich 2-hydroxy-3-nitrocyclopentanone derivatives. The reactions ...

journal_title：Chirality

authors： Felluga F,Forzato C,Nitti P,Pitacco G,Prati F,Valentin E,Zangrando E

更新日期：2012-12-01 00:00:00

abstract：:The UV absorption and electronic circular dichroism (ECD) spectra of (R)- and (S)-nicotine and (S)-nornicotine in aqueous solution were measured to a significantly lower wavelength range than previously reported, allowing the identification of four previously unobserved electronic transitions. The ECD spectra of the t...

journal_title：Chirality

authors： Clayton PM,Vas CA,Bui TT,Drake AF,McAdam K

更新日期：2013-05-01 00:00:00

abstract：:Nine patients taking oral doses of 10 mg/12 h rac-pindolol as part of their treatment for hypertension in pregnancy were recruited for the study. Maternal and fetal gestational age ranged from 20-38 years and 28-41 weeks, respectively. Blood was collected from the umbilical cord vein and from the mother from zero to 1...

journal_title：Chirality

authors： Gonçalves PV,Matthes Ado C,Da Cunha SP,Lanchote VL

更新日期：2002-08-01 00:00:00

abstract：:We present a new concept of synthesis for preparation of molecularly imprinted polymers using a functionalized initiator to replace the traditional functional monomer. Using propranolol as a model template, a carboxyl-functionalized radical initiator was demonstrated to lead to high-selectivity polymer particles prepa...

journal_title：Chirality

authors： Liu W,Holdsworth C,Ye L

更新日期：2020-03-01 00:00:00

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...

journal_title：Chirality

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

更新日期：2009-04-01 00:00:00

abstract：:A calculation of the circular dichroism (CD) spectra of carbonmonoxy- and deoxy-myoglobin is carried out in relation to a time-resolved CD experiment. This calculation allows us to assign a dominant role to the proximal histidine in the definition of the electronic normal modes and to interpret the transient CD struct...

journal_title：Chirality

authors： Dartigalongue T,Hache F

更新日期：2006-05-05 00:00:00

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...

journal_title：Chirality

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

更新日期：2010-06-01 00:00:00

abstract：:Supercritical fluid chromatography (SFC) is already used for enantioseparation in the pharmaceutical industry, but it is rarely used for the separation of chiral pesticides. Comparing with high performence liquid chromatography, SFC uses much more environmnetal friendly and economic mobile phase, supercritical CO2 . I...

journal_title：Chirality

authors： Zhao L,Xie J,Guo F,Liu K

更新日期：2018-05-01 00:00:00

abstract：:The stereolability of chiral Hoveyda-Grubbs II type ruthenium complexes bearing N-heterocyclic carbene (NHC) ligands with Syn-phenyl groups on the backbone and Syn- or Anti-oriented o-tolyl N-substituents was studied by resorting to dynamic high-performance liquid chromatography (D-HPLC). A complete chromatographic pi...

journal_title：Chirality

authors： Menta S,Pierini M,Cirilli R,Grisi F,Perfetto A,Ciogli A

更新日期：2015-10-01 00:00:00