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

abstract：:Ninety isolates of microorganisms belonging to different taxonomical groups (30 bacteria, 20 yeast, and 40 fungi) were previously isolated from various samples. These isolates were screened as reducing agents for acetophenone 1a to phenylethanol 2a. It was found that the isolate EBK-10 was the most effective biocataly...

journal_title：Chirality

authors： Zilbeyaz K,Kurbanoglu EB

更新日期：2010-10-01 00:00:00

abstract：:Integrating spheres are widely used with UV-Vis and occasionally with infrared spectrophotometers to measure different types of samples, either in transmission mode (scattered transmission accessories) or in total/diffuse reflectance mode. We built a prototype sphere of the demountable type, which fits easily the samp...

journal_title：Chirality

authors： Castiglioni E,Albertini P

更新日期：2000-05-01 00:00:00

abstract：:Racemic 1-phenylethylamine was optically resolved by its own derivative formed with glutaric acid namely (+)-(R)-N-(1-phenylethyl)glutaramic acid. The amide acid resolving agent was synthesized from (+)-(R)-1-phenylethylamine by N-derivatization. The glutaric acid derivative was the next in a homologous series of dica...

journal_title：Chirality

authors： Schindler J,Egressy M,Bereczki L,Pokol G,Fogassy E,Marthi K

更新日期：2007-03-01 00:00:00

abstract：:Novel chiral diisopropyl spiro bis(isoxazoline) ligands, anti-i-Pr-SPRIX and syn-i-Pr-SPRIX, were designed and synthesized. Their catalytic utility, X-ray crystallographic analyses, and complexation studies demonstrated the structural features of tetraisopropyl spiro bis(isoxazoline) ligand, i-Pr-SPRIX, which is a pro...

journal_title：Chirality

authors： Takenaka K,Lin X,Takizawa S,Sasai H

更新日期：2015-08-01 00:00:00

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...

journal_title：Chirality

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

更新日期：2007-07-01 00:00:00

abstract：:We report here a sensitive method for the determination of the absolute configurations of primary amines using exciton-coupled circular dichroism (ECCD). The method works on a microgram scale by derivatization of chiral amines with quinoline chromophores. Complexation of the chiral ligands with metal ion fixes the geo...

journal_title：Chirality

authors： Zhang J,Holmes AE,Sharma A,Brooks NR,Rarig RS,Zubieta J,Canary JW

更新日期：2003-02-01 00:00:00

abstract：:A series of representative optically active derivatives of 4-hydroxy-5-alkylcyclopent-2-en-1-one were prepared from the respective 2-furyl methyl carbinols via the Piancatelli rearrangement followed by the enzymatic kinetic resolution of racemates. Applicability of chiroptical methods (experimental and calculated elec...

journal_title：Chirality

authors： Frelek J,Karchier M,Madej D,Michalak K,Różański P,Wicha J

更新日期：2014-06-01 00:00:00

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...

journal_title：Chirality

authors： Wuethrich A,Haddad PR,Quirino JP

更新日期：2014-11-01 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：:Racemic N-methyl-N-(1-methyl-4-pyrrolidino-2-butynyl)acetamide (BM-5), a putative postsynaptic agonist and presynaptic antagonist at muscarinic receptors, was resolved into the enantiomers by a new method suitable for large scale preparation. The method involves a chemoselective N-debenzylation as the key step. The en...

journal_title：Chirality

authors： Nilsson BM,De Boer P,Grol CJ,Hacksell U

更新日期：1992-01-01 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：:This work reports confirmation of the experimental assignment of the absolute-handedness chirality of single-walled carbon nanotubes (SWNTs). This was achieved by applying the scanning tunneling microscopy (STM) imaging technique to a supramolecular composite consisting of a metalized porphyrin derivative (nickel-5,15...

journal_title：Chirality

authors： Abd El-Mageed AIA,Ogawa T

更新日期：2020-03-01 00:00:00

abstract：:The chiral separation by counter-current chromatography has made great progress in the past three decades. It has become increasingly popular in the field of chiral separation, and many applications have been introduced during the last years. This review mainly focuses on the current topics, applications, and trends i...

journal_title：Chirality

authors： Duan WD,Huang XY,Di DL

更新日期：2020-10-01 00:00:00

abstract：:The direct separation of the enantiomers of 1-(α-aminoarylmethyl)-2-naphthol, 1-(α-aminoalkyl)-2-naphthol, 2-(α-aminoarylmethyl)-1-naphthol analogs, and 2-(1-amino-2-methylpropyl)-1-naphthol) was performed on a newly developed chiral stationary phase containing isopropyl carbamate-cyclofructan6 as chiral selector, wit...

journal_title：Chirality

authors： Aranyi A,Ilisz I,Pataj Z,Szatmári I,Fülöp F,Armstrong DW,Péter A

更新日期：2011-08-01 00:00:00

abstract：:The pharmacokinetics of (-)-N-(trans-4-isopropylcyclohexanecarbonyl)-D-phenylalanine (nateglinide) and its enantiomer (L-enantiomer) was studied in Goto-Kakizaki (GK) rats after intravenous administration of nateglinide or L-enantiomer at a dose of 40 micromol/kg body weight. Nateglinide, its L-enantiomer and their me...

journal_title：Chirality

authors： Tamura M,Shiba S,Kudo N,Kawashima Y

更新日期：2010-01-01 00:00:00

abstract：:Two "click" binaphthyl chiral stationary phases were synthesized and evaluated by liquid chromatography. Their structures incorporate S-(-)-1,1'-binaphthyl moiety as the chiral selector and 1,2,3-triazole ring as the spacer. These chiral stationary phases (CSPs) allowed the efficient resolution for a wide range of rac...

journal_title：Chirality

authors： Yu H,Yin C,Jia C,Jin Y,Ke Y,Liang X

更新日期：2012-05-01 00:00:00

abstract：:rac-Isradipine is a dihydropyridine type calcium antagonist. Its calcium entry blocking effect is due primarily to the (+)-(S)-enantiomer. This study describes a sensitive enantioselective method for the determination of isradipine in human serum. Following alkaline extraction into hexane, the enantiomers of isradipin...

journal_title：Chirality

authors： Rask HS,Angelo HR,Christensen HR

更新日期：1998-01-01 00:00:00

abstract：:A systematic and comprehensive study of the conformational spaces of the Cinchona alkaloids quinine, quinidine, cinchonine, cinchonidine, epiquinine, epiquinidine, epicinchonine, and epicinchonidine using the semiempirical PM3 method is described. The results were analyzed in terms of syn/anti and open/closed/hindered...

journal_title：Chirality

authors： Caner H,Biedermann PU,Agranat I

更新日期：2003-08-01 00:00:00

abstract：:The hydrolysis and acyl migration of biosynthetic S-naproxen-beta-l-O-acyl glucuronide (I) and R-naproxen-beta-l-O-acyl glucuronide (II) was followed by HPLC. Nine first-order kinetic rate constants for the hydrolysis and acyl migration between the beta-l-O-acyl glucuronide, its alpha/beta-2, alpha/beta-3-, alpha/beta...

journal_title：Chirality

authors： Mortensen RW,Sidelmann UG,Tjørnelund J,Hansen SH

更新日期：2002-05-05 00:00:00

abstract：:One of the most powerful techniques that are currently available to measure thermodynamic parameters such as enthalpy (ΔH), Gibbs free energy (ΔG), entropy changes (ΔS), and binding affinity in chemical reactions is isothermal titration calorimetry (ITC). Recent advances in instrumentation have facilitated the develop...

journal_title：Chirality

authors： Werber L,Mastai Y

更新日期：2018-05-01 00:00:00

abstract：:Six secondary phosphine oxides and their tautomeric equilibria as free ligands and in the presence of an equimolar amount of the chiral dirhodium complex Rh* are described and discussed. Discrimination of enantiomers is easily possible by inspecting the (31)P NMR resonances; some (1)H and (13)C NMR resonances are usef...

journal_title：Chirality

authors： Magiera D,Szmigielska A,Pietrusiewicz KM,Duddeck H

更新日期：2004-01-01 00:00:00

abstract：:There is a great deal of current interest in the role and importance of chirality in the development of new drugs, but little attention is being paid to the stereochemistry of older drugs. Indeed, many older chiral drugs were introduced without adequate information on their stereochemical identity or composition. We h...

journal_title：Chirality

authors： Nusser E,Banerjee A,Gal J

更新日期：1991-01-01 00:00:00

abstract：:Novel enantiopure 1,2,4-trizole-3-thiones containing a benzensulfonamide moiety were synthesized via multistep reaction sequence starting with D-phenylalanine methyl ester and L-phenylalanine ethyl ester as a source of chirality. The chemical structures of all compounds were characterized by elemental analysis, UV, IR...

journal_title：Chirality

authors： Başaran E,Karaküçük-Iyidoğan A,Schols D,Oruç-Emre EE

更新日期：2016-06-01 00:00:00

abstract：:6-Fluoro-2-methyl-1,2,3,4-tetrahydroquinoline (FTHQ) enantiomers were separated by supercritical fluid extraction using carbon dioxide. Diastereoisomeric salts were formed from the racemic base with less than one equivalent of O,O'-di-(4-toluoyl)-(2R,3R)-tartaric acid (DPTTA). Further purification was achieved by part...

journal_title：Chirality

authors： Kmecz I,Simándi B,Bálint J,Székely E,Fogassy E,Kemény S

更新日期：2001-01-01 00:00:00

abstract：:Chiral sulfoxides/N-oxides (R)-1 and (R,R)-2 are effective chiral promoters in the enantioselective allylation of α-keto ester N-benzoylhydrazone derivatives 3a-g to generate the corresponding N-benzoylhydrazine derivatives 4a-g, with enantiomeric excesses as high as 98%. Representative hydrazine derivatives 4a-b were...

journal_title：Chirality

authors： Reyes-Rangel G,Bandala Y,García-Flores F,Juaristi E

更新日期：2013-09-01 00:00:00

abstract：:New chiral derivatizing reagents (CDAs) derived from trans-1,2-diaminocyclohexane, having an electron-deficient aromatic substituent (either an aromatic imide or 3,5-dinitrobenzamide) and rigid structure (either an amide or a urea linker), are reported. Significant shift differences of diastereotopic protons in the 1H...

journal_title：Chirality

authors： Kaik M,Gajewy J,Grajewski J,Gawronski J

更新日期：2008-03-01 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：:Mirror symmetry breaking is ubiquitous in our visible universe taking place in elementary particles, atoms, and molecules. Molecular chirality is not biogenic in itself, although its detection is often considered a biosignature, a conjecture inferred from the fact that we do not know life devoid of homochirality. The ...

journal_title：Chirality

authors： Cintas P,Viedma C

更新日期：2012-11-01 00:00:00

abstract：:Enzymatic hydrolysis with beta-glucuronidase/sulfatase was used for the enantioselective determination of N-hydroxymexiletine glucuronide in plasma for pharmacokinetic studies. N-Hydroxymexiletine glucuronide was determined as the quantity of mexiletine released by hydrolysis (difference between the enantiomeric conce...

journal_title：Chirality

authors： Lanchote VL,Santos VJ,Cesarino EJ,Dreossi SA,Mere Júnior Y,Santos SR

更新日期：1999-01-01 00:00:00

abstract：:(S)-(-)-2-(α-hydroxyethyl)-benzimidazole and (S)-(+)-2-(α-hydroxybenzyl)-benzimidazole work as chiral Brønsted bases (BBs) in Diels-Alder reaction between anthrone and maleimides under mild reaction condition. These chiral BBs cause asymmetric induction. ...

journal_title：Chirality

authors： Mirgane NA,Karnik AV

更新日期：2011-05-01 00:00:00