Spectroscopic properties of the nonplanar amide group: a computational study.

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：: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：:(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

abstract：:Previously, a diazaphospholidine has been synthesized and evaluated as a chiral derivatizing reagent for the determination of the optical purity of chiral alcohols via 31P NMR spectroscopy (Alexakis et al., J. Org. Chem. 57:1224-1237, 1992). Our laboratory is interested in the advantageous and practical applications o...

journal_title：Chirality

authors： House KL,O'Connor MJ,Silks LA 3rd,Dunlap RB,Odom JD

更新日期：1994-01-01 00:00:00

abstract：:Perfluorooctane sulfonate (PFOS) is one of the most frequently detected perfluoroalkyl substances in environmental and human samples. Previous studies have shown that nonracemic PFOS in biological samples can be used as a marker of PFOS exposure sources. In recent years, supercritical fluid chromatography (SFC) has em...

journal_title：Chirality

authors： Zhao L,Chen F,Guo F,Liu W,Liu K

更新日期：2019-10-01 00:00:00

abstract：:Weinreb amide 3 was synthesized using isobutyl chloroformate, carbonyldiimidazole, or ethylcarbodiimide as the coupling agent in the reaction of Boc-phenylalanine with O,N-dimethylhydroxylamine hydrochloride. An optically active oil was isolated along with an optically inactive solid irrespective of the type of coupli...

journal_title：Chirality

authors： Zheng X,Donkor IO,Miller DD,Ross CR 2nd

更新日期：2000-01-01 00:00:00

abstract：:The direct asymmetric aldol reactions of equivalent molar amounts of aldehydes and ketones were carried out at -20 degrees C over alkaline Al(2)O(3) with 20 mol % of Pro-Trp as catalyst and 20 mol % of N-methylmorpholine or 1,4-diazabicyclo[2.2.2]octane as additive. After simple and environmentally friendly work-up, m...

journal_title：Chirality

authors： Lei M,Xia S,Wang J,Ge Z,Cheng T,Li R

更新日期：2010-06-01 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：:Enantioselective catalytic epoxidation of olefins is an important problem from both practical and mechanistic points of view. The origins of chiral induction by asymmetric porphyrin and salen complexes were investigated by FT-NMR T1 relaxation techniques. A new chiral vaulted porphyrin (1) that carries (S)-binaphthyl-...

journal_title：Chirality

authors： Groves JT,Crowley SJ,Shalyaev KV

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：:3alpha,12alpha-dihydroxy-5beta-cholan-24-oic acid (deoxycholic acid DCA) is able to discriminate between the R- and S-enantiomers of camphorquinone and endo-(+)-3-bromocamphor and select only the S-enantiomers from a racemic mixture. DCA forms novel well ordered 1:1 adducts with (1S)-(+)-camphorquinone and (1S)-endo-(...

journal_title：Chirality

authors： Tahir MI,Rees NH,Heyes SJ,Cowley AR,Prout K

更新日期：2008-07-01 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：:N-formylphenylalanine was subjected to optical resolution using a chiral agent such as phenylethylamine enantiomer, (R)-phenylglycine methyl ester, (S)-N-benzyl-2-aminobutanol, alone or in a mixture with each other or in a mixture with benzylamine. ...

journal_title：Chirality

authors： Pálovics E,Fogassy E,Schindler J,Nógrádi M

更新日期：2007-01-01 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：: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 ...

journal_title：Chirality

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

更新日期：2005-02-01 00:00:00

abstract：:Treatment of benzoate, formate, or trifluoroacetate esters with silyldibromomethyllithiums provides alkyl silyl mixed acetals via the 1,3-rearrangement of a silyl group from carbon to oxygen. A high level of asymmetric induction onto the acetal carbon is observed when chiral alkyl esters are employed. The stereochemic...

journal_title：Chirality

authors： Shinokubo H,Kondo J,Inoue A,Oshima K

更新日期：2003-01-01 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：:The use of stereodynamic probes is becoming one of the leading strategies for the fast and effective determination of enantiomeric excess. Recently, we reported a series of novel molecular architectures based on a modified tris(2-pyridylmethyl)amine complex (TPMA), which are able to amplify the electronic CD, in the c...

journal_title：Chirality

authors： Carmo Dos Santos NA,Badetti E,Licini G,Abbate S,Longhi G,Zonta C

更新日期：2018-01-01 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：:Numbers of resolving factors were investigated to improve resolution of venlafaxine 1. An effective resolving agent, O,O'-di-p-toluoyl-(R, R)-tartaric acid 2, was screened using similar method of 'Dutch resolution' from tartaric acid derivatives. The resolution efficiency was up to 88.4%, when the ratio of rac-1 and 2...

journal_title：Chirality

authors： Liu ZJ,Liu H,Chen XW,Lin M,Hu Y,Tuo X,Yuan ZY,Sun XX

更新日期：2018-03-01 00:00:00

abstract：:Spontaneous symmetry breaking in reactive systems, known as a rare physical phenomenon and for the Soai autocatalytic irreversible reaction, might in principle also occur in other, more common asymmetric reactions when the chiral product is capable to promote its formation and an element of "nonlinearity" is involved ...

journal_title：Chirality

authors： Mauksch M,Tsogoeva SB,Wei S,Martynova IM

更新日期：2007-11-01 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：:Chirality is often glossed over in theoretical or experimental discussions concerning the origin of life, but the ubiquity of homochiral building blocks in known biological systems demands explanation. Information theory can provide a quantitative framework for understanding the role of chirality in biology. Here I sh...

journal_title：Chirality

authors： Carroll JD

更新日期：2009-03-01 00:00:00

abstract：:A new enantiomerically pure P-chiral phosphine, (S)-cyclohexylmethyl- (1-naphthyl)phosphine (1) was prepared by phosphine-borane methodology and used in a mechanistic study of the Mitsunobu reaction. Enantiomerically enriched (S)-cyclo- hexylmethyl(1-naphtyl)phosphine oxide (8) is obtained if the reaction proceeds thr...

journal_title：Chirality

authors： Watanabe T,Gridnev ID,Imamoto T

更新日期：2000-06-01 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 application of helical poly[(S)-3-vinyl-2,2'-dihydroxy-1, 1'-binaphthyl] (L*) in the asymmetric borane reduction of prochiral ketones was studied. The results showed that L* had excellent catalytic activity as well as enantioselectivity, giving up to 96% yield and up to 99% enantiomeric excess (ee) of the correspo...

journal_title：Chirality

authors： Qin G,Chen Y,Yang L,Yang N,Yang Z

更新日期：2015-07-01 00:00:00

abstract：:Two new carotenoids, sapotexanthin 5,6-epoxide and sapotexanthin 5,8-epoxide, have been isolated from the ripe fruits of red mamey (Pouteria sapota). Sapotexanthin 5,6-epoxide was also prepared by partial synthesis via epoxidation of sapotexanthin, and the (5R,6S) and (5S,6R) stereoisomers were identified by high-perf...

journal_title：Chirality

authors： Murillo E,Agócs A,Nagy V,Király SB,Kurtán T,Toribio EM,Lakey-Beitia J,Deli J

更新日期：2020-05-01 00:00:00

abstract：:In the presence of tridentate chiral ligand 4e, 99% e.e. value was obtained by asymmetric reduction of ethyl benzoylacetate with borane in toluene at 25 degrees C. Various ligands and reaction conditions were investigated to develop a reasonable mechanism that explains the experimental outcomes. ...

journal_title：Chirality

authors： Lee DS

更新日期：2007-02-01 00:00:00

abstract：:The electronic circular dichroism (ECD) spectra of two sesquiterpenoids (1 and 2) related to oplopanone, obtained from a methanolic extract of the plant Serphidium stenocephalum (Artemisia stenocephala), were measured and reproduced by means of time-dependent density functional theory (TDDFT) calculations, establishin...

journal_title：Chirality

authors： Shafiq N,Saleem M,Riaz N,Tousif MI,Jabbar A,Tareen RB,Pescitelli G

更新日期：2014-01-01 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