Unusual temperature-induced retention behavior of constrained β-amino acid enantiomers on the zwitterionic chiral stationary phases ZWIX(+) and ZWIX(-).

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：:Chiral pesticides are now receiving more and more attention in the food-making process. This experiment studied the enantioselective behavior of diclofop-methyl (DM) and its main metabolite, diclofop (DC), during the soy sauce brewing process. Two kinds of commonly used strains, Aspergillus oryzae and Saccharomyces ro...

journal_title：Chirality

authors： Lu Y,Zhang D,Liao Y,Diao J,Chen X

更新日期：2016-01-01 00:00:00

abstract：:A sensitive and stereospecific liquid chromatography-tandem mass spectrometry method for the quantitative determination of TWo8 enantiomers ((2RS)-1-(7-methoxy-1H-indol-4-yloxy)-3-(2-(2-methoxyphenoxy)ethylamino)-propan-2-ol) was developed and validated in rat serum and some tissues. Racemic TWo8 is a new chemical ent...

journal_title：Chirality

authors： Walczak M,Szymura-Oleksia J,Groszek G

更新日期：2012-08-01 00:00:00

abstract：:A simple, green, and direct three-component condensation of acetophenone, aromatic aldehydes with 3-oxo-N-phenylbutanamide (acetoacetanilide) to generate some novel (1S,6R)/(1R,6S)-2-oxo-N,4,6-triarylcyclohex-3-enecarboxamide derivatives was carried out over K2 CO3 (10 mol%) with high efficiency in water/ethanol as gr...

journal_title：Chirality

authors： Mousavi SR

更新日期：2016-11-01 00:00:00

abstract：:The enantioselective hydrogenation of C==N-C group containing compounds over modified metal catalysts is as yet an uninvestigated research area. This work contains results obtained on the hydrogenation of 1-pyrroline-2-carboxylate esters and sodium salt over cinchona alkaloid-modified alumina-supported Pd catalyst. Th...

journal_title：Chirality

authors： Szöllösi G,Kun I,Bartók M

更新日期：2001-01-01 00:00:00

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 × ...

journal_title：Chirality

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

更新日期：2018-04-01 00:00:00

abstract：:Kinetic and equilibrium binding studies were performed on the interaction of warfarin enantiomers with human serum albumin (HSA) in the absence and presence of lorazepam acetate (LoAc) enantiomers. Binding kinetics were followed by recording changes in the fluorescence of warfarin upon binding to HSA using the stopped...

journal_title：Chirality

authors： Fitos I,Visy J,Kardos J

更新日期：2002-05-15 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 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 stere...

journal_title：Chirality

authors： Zsila F,Hollósi M,Gergely A

更新日期：2000-11-01 00:00:00

abstract：:Four racemic esters of (1R*,7aR*)-3,6,7,7a-tetrahydro-1-hydroxy-7a-methyl-1H-inden-5(2H)-one were prepared and subjected to hydrolysis with two types of hydrolases, including alcalase and three lipases. Alcalase and lipase showed opposite enantiopreference on these esters. Based on this result, we developed a gram-sca...

journal_title：Chirality

authors： Lo LC,Chou TC,Shie JJ

更新日期：2004-05-05 00:00:00

abstract：:Immobilized Cu(OAc)(2)-bis(oxazolines) via hydrogen bonding by SBA-15 was applied to asymmetric Henry reaction, and good enantioselectivities were obtained (up to 83% ee) between 2-methoxybenzaldehyde and CH(3)NO(2) in isopropyl alcohol (iPrOH). The catalyst could be reused seven times without any obvious loss in enan...

journal_title：Chirality

authors： Li ZH,Zhou ZM,Hao XY,Zhang J,Dong X,Liu YQ

更新日期：2012-12-01 00:00:00

abstract：:A selection of my work on chirality is sketched in two distinct parts of this lecture. Symmetry and Chirality explains how the discrete symmetries of parity P, time reversal T, and charge conjugation C may be used to characterize the properties of chiral systems. The concepts of true chirality (time-invariant enantiom...

journal_title：Chirality

authors： Barron LD

更新日期：2012-11-01 00:00:00

abstract：:The assignment of the absolute configuration of novel anti-inflammatory pyrrole derivatives has been accomplished by a combined strategy based on independent physical methods. The key step of our stereochemical characterization approach is the production at mg-scale of enantiomerically pure forms by HPLC on Chiralpak ...

journal_title：Chirality

authors： Biava M,Cirilli R,Fares V,Ferretti R,Gallinella B,La Torre F,Poce G,Porretta GC,Supino S,Villani C

更新日期：2008-06-01 00:00:00

abstract：:We have previously shown that (RS)-2-amino-2-(5-tert-butyl-3-hydroxyisoxazol-4-yl)acetic acid (ATAA) is an antagonist at N-methyl-D-aspartic acid (NMDA) and (RS)-2-amino-3-(3-hydroxy-5-methylisoxazol-4-yl)propionic acid (AMPA) receptors. We have now resolved ATAA via diastereomeric salt formation using N-BOC protected...

journal_title：Chirality

authors： Johansen TN,Frydenvang K,Ebert B,Madsen U,Krogsgaard-Larsen P

更新日期：1997-01-01 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：:The resolution methods applying (-)-(4R,5R)-4,5-bis(diphenylhydroxymethyl)-2,2-dimethyldioxolane ("TADDOL"), (-)-(2R,3R)-α,α,α',α'-tetraphenyl-1,4-dioxaspiro[4.5]decan-2,3-dimethanol ("spiro-TADDOL"), as well as the acidic and neutral Ca(2+) salts of (-)-O,O'-dibenzoyl- and (-)-O,O'-di-p-toluoyl-(2R,3R)-tartaric acid ...

journal_title：Chirality

authors： Bagi P,Fekete A,Kállay M,Hessz D,Kubinyi M,Holczbauer T,Czugler M,Fogassy E,Keglevich G

更新日期：2014-03-01 00:00:00

abstract：:Anodic oxidation of 1-acetoxy-3,4-dihydronaphthalene (1) and alpha-acetoxy-beta-alkylstyrenes (3) at -78 degrees C in a mixed solvent of acetonitrile (CH(3)CN), tetrahydrofuran (THF), and acetic acid (AcOH) containing (S)-tetraethylammonium camphorsulfonate as a chiral supporting electrolyte brought about enantioselec...

journal_title：Chirality

authors： Maekawa H,Itoh K,Goda S,Nishiguchi I

更新日期：2003-01-01 00:00:00

abstract：:A three-dimensional molecularly imprinted overoxidized polypyrrole/MnO2 /carbon felt (MIOPPy/MnO2 /CF) composites were fabricated, which results in increased active area of the surface of the molecularly imprinted polymers film and greatly improved electrochemical chiral recognition effect for tryptophan isomers. The ...

journal_title：Chirality

authors： Dong L,Liu X,Xu H,Wu D,Gao S,Zhong L,Kong Y

更新日期：2019-11-01 00:00:00

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...

journal_title：Chirality

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

更新日期：2009-11-01 00:00:00

abstract：:The chiral squaramide catalysts (8-15) were synthesized, and their catalytic efficiency in the enantioselective conjugate addition of pyrazolones to nitroalkenes was described. This protocol provides excellent chemical yields (up to 93%) of chiral 5-methyl-4-(2-nitro-1-arylethyl)pyrazol-3-ol derivatives with high enan...

journal_title：Chirality

authors： Aydin AE,Culha S

更新日期：2021-01-11 00:00:00

abstract：:Reaction of (S)- or (R)-3-aminoquinuclidine with 2-chloropyrimidine or 2-bromopyrimidine led to an unexpected formation of both cis- and trans-octahydropyrrolo [2,3]pyridine derivatives. A single-step synthesis of two of the four stereoisomers of these octahydropyrrolo[2,3]pyridine derivatives provides a convenient wa...

journal_title：Chirality

authors： Goljer I,Molinari A,He Y,Nogle L,Sun W,Campbell B,McConnell O

更新日期：2009-07-01 00:00:00

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 ...

journal_title：Chirality

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

更新日期：2013-12-01 00:00:00

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：:We study the chiroptical properties of one-dimensional photonic crystals supporting superchiral surface waves by introducing a simple formalism based on the Fresnel reflection matrix. We show that the proposed framework provides useful insights on the behavior of all the relevant chiroptical quantities, allowing for a...

journal_title：Chirality

authors： Pellegrini G,Finazzi M,Celebrano M,Duò L,Biagioni P

更新日期：2018-07-01 00:00:00

abstract：:Despite that a number of experimental and theoretical investigations have been carried out to determine the structure of trialanine in water, the reported populations of polyproline II (PPII) and β-strand conformers vary and were found to be dependent on which spectroscopic method was used. Such discrepancies are due ...

journal_title：Chirality

authors： Oh KI,Lee KK,Park EK,Yoo DG,Hwang GS,Cho M

更新日期：2010-01-01 00:00:00

abstract：:Human carboxylesterase 1 (hCES1) is an enzyme that plays an important role in hydrolysis of pharmaceuticals in the human liver. In this study, elucidation of the chiral recognition ability of hCES1 was attempted using indomethacin esters in which various chiral alcohols were introduced. Indomethacin was condensed with...

journal_title：Chirality

authors： Takahashi M,Takani D,Haba M,Hosokawa M

更新日期：2020-01-01 00:00:00

abstract：:Here, we report the general strategies by which NMR spectroscopy can be used to determine the enantiopurity and absolute configuration of chalcogen containing secondary alcohols, including the evaluation of the use of chiral solvating and chiral derivatizing agents. The BINOL/DMAP ternary complex demonstrated a simple...

journal_title：Chirality

authors： Marques NBG,Jacob RG,Perin G,Lenardão EJ,Alves D,Silva MS

更新日期：2019-01-01 00:00:00

abstract：:The influence of endotoxin-induced inflammation on the enantioselective pharmacokinetics of propranolol, oxprenolol, and verapamil, which bind to alpha 1-acid glycoprotein, was studied in the rat. The racemic mixtures were given orally. In the control animals, for propranolol and oxprenolol, the plasma concentrations ...

journal_title：Chirality

authors： Laethem ME,Belpaire FM,Wijnant P,Rosseel MT,Bogaert MG

更新日期：1994-01-01 00:00:00

abstract：:The five-steps synthesis of a hemicryptophane cage combining a benzene-1,3,5-tricarboxamide unit and a cyclotriveratrylene (CTV) moiety is described. Chiral high-performance liquid chromatography (HPLC) was used to resolve the racemic mixture. The absolute configuration of the isolated enantiomers was assigned by comp...

journal_title：Chirality

authors： Long A,Jean M,Albalat M,Vanthuyne N,Giorgi M,Górecki M,Dutasta JP,Martinez A

更新日期：2019-11-01 00:00:00

abstract：:1alpha,25-Dihydroxyvitamin D(3) (1alpha,25(OH)2D3) has been shown to modulate not only proliferation and differentiation, but also apoptosis in malignant cells, indicating that it could be useful for the treatment of cancer and psoriasis. However, little information has been available on the binding conformation of th...

journal_title：Chirality

authors： Mikami K,Ohba S,Ohmura H,Kubodera N,Nakagawa K,Okano T

更新日期：2001-07-01 00:00:00