Abstract:
:Doping nematic liquid crystals with nonracemic chiral compounds induces a twisted nematic (cholesteric) phase. The ability of solutes to twist the nematic phase may be related to the overall shape of the chiral dopant and consequently to its absolute configuration. The cholesteric induction is therefore a powerful tool complementary to chiroptical techniques to obtain stereochemical information on chiral molecules.
journal_name
Chiralityjournal_title
Chiralityauthors
Pieraccini S,Ferrarini A,Spada GPdoi
10.1002/chir.20482subject
Has Abstractpub_date
2008-05-15 00:00:00pages
749-59issue
5eissn
0899-0042issn
1520-636Xjournal_volume
20pub_type
杂志文章相关文献
CHIRALITY文献大全abstract::Antimalarial drugs have shown potential in suppressing the role of glycosaminoglycans (GAGs) in the pathology of prion protein conformational disorders (e.g. "Mad Cow" disease) by competing for sites of electrostatic interaction. In this study, circular dichroism (CD) and UV/Visible (UV/Vis) absorption spectroscopy te...
journal_title:Chirality
pub_type: 杂志文章
doi:10.1002/chir.20873
更新日期:2011-01-01 00:00:00
abstract::The chiral fungicide furametpyr is widely used in the rice field to control rice sheath blight; however, furametpyr enantiomers are treated as just one compound in traditional achiral analysis, which gives only partial information. An effective chiral analytical method was developed for the resolution and determinatio...
journal_title:Chirality
pub_type: 杂志文章
doi:10.1002/chir.22232
更新日期:2013-12-01 00:00:00
abstract::After alkylation of a fraction of the total alpha-adrenoreceptors by phenoxybenzamine in rat vas deferens, the dissociation constants of (-)- and (+)-epinephrine in functional studies were 7 X 10(-7) M and 2 X 10(-5) M, respectively. In the adrenoreceptor-containing tissue fraction, when 3H-labeled WB4101 was used as ...
journal_title:Chirality
pub_type: 杂志文章
doi:10.1002/chir.530010106
更新日期:1989-01-01 00:00:00
abstract::The enantiomerization and enantioselective bioaccumulation of metalaxyl by a single dose of exposure to Tenebrio molitor larvae under laboratory condition were studied by high-performance liquid chromatography tandem mass spectroscopy (HPLC-MS/MS) based on a ChiralcelOD-3R [cellulosetris-tris-(3, 5-dichlorophenyl-carb...
journal_title:Chirality
pub_type: 杂志文章
doi:10.1002/chir.22269
更新日期:2014-02-01 00:00:00
abstract::Vitamin E is an essential nutrient of still increasing economic importance. Vitamin E derivatives include many nonracemic chiral compounds whose chirooptical characterization is scarcely described in the literature. We report the CD spectra of delta-tocopherol and its unsaturated analog delta-tocotrienol. TDDFT calcul...
journal_title:Chirality
pub_type: 杂志文章
doi:10.1002/chir.20591
更新日期:2009-01-01 00:00:00
abstract::4-l-menthyloxycarbonyl 5-aryl prolinates were studied as organocatalysts of a novel three-component reaction of cyclohexanone, benzoic acid, and β-nitrostyrene. The presence of ortho-halogen atom in 5-aryl fragment of the catalyst is favored for driving the formation of chiral 7a-hydroxyoctahydro-2H-indol-2-one scaffo...
journal_title:Chirality
pub_type: 杂志文章
doi:10.1002/chir.23212
更新日期:2020-06-01 00:00:00
abstract::The elusive epimerization process in the chiral butenolide moiety of Annonaceous acetogenins was examined under several sets of conditions commonly used for elimination leading to the alpha, beta-unsaturated lactone and the results provide practical guidance in choosing elimination conditions. ...
journal_title:Chirality
pub_type: 杂志文章
doi:10.1002/(SICI)1520-636X(2000)12:3<127::AID-CHIR4>3
更新日期:2000-03-01 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
pub_type: 杂志文章
doi:10.1002/chir.20942
更新日期:2011-05-01 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
pub_type: 杂志文章,评审
doi:10.1002/chir.22842
更新日期:2018-05-01 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
pub_type: 杂志文章
doi:10.1002/chir.10158
更新日期:2003-02-01 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
pub_type: 杂志文章
doi:10.1002/chir.20254
更新日期:2006-05-05 00:00:00
abstract::The perturbation of the racemic equilibrium of luminescent D3 terbium(III) complexes with chelidamic acid (CDA), a hydroxylated derivative of 2,6-pyridine-dicarboxylic acid (DPA), by added chiral biomolecules such as L-amino acids has been studied using circularly polarized luminescence and 13C NMR spectroscopy. It is...
journal_title:Chirality
pub_type: 杂志文章
doi:10.1002/chir.20628
更新日期:2009-05-01 00:00:00
abstract::8-Prenylnaringenin (8PN) is a naturally occurring bioactive chiral prenylflavonoid found most commonly in the female flowers of hops (Humulus lupulus L.). A stereospecific method of analysis for 8PN in biological fluids is necessary to study the pharmacokinetic disposition of each enantiomer. A novel and simple liquid...
journal_title:Chirality
pub_type: 杂志文章
doi:10.1002/chir.22343
更新日期:2014-08-01 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
pub_type: 杂志文章
doi:10.1002/chir.530030103
更新日期:1991-01-01 00:00:00
abstract::In this research, 10 chiral pesticides in fruits and vegetables were simultaneously determined using chiral liquid chromatography triple quadrupole-linear ion trap hybrid mass spectrometry (LC-QqLIT). The QuEChERS method was applied for sample preparation, and an enhanced product ion (EPI) scan was used to acquire tan...
journal_title:Chirality
pub_type: 杂志文章
doi:10.1002/chir.22531
更新日期:2015-12-01 00:00:00
abstract::In this review article we examine state-of-the-art techniques for the structural elucidation of organic compounds isolated from natural sources. In particular, we focus on the determination of absolute configuration (AC), perhaps the most challenging but inevitable step in the whole process, especially when newly isol...
journal_title:Chirality
pub_type: 杂志文章,评审
doi:10.1002/chir.20795
更新日期:2009-01-01 00:00:00
abstract::Synthesis and catalyst performance of 2,3- (types and ) and 2,8-disubstituted (type ) thiourea bifunctional organocatalysts was attempted. The synthesis of catalyst of type has, so far, not been realized, while catalysts of type , i.e., the 2,3-exo- and the 2-endo-3-exo-thiourea catalysts, were prepared in six steps s...
journal_title:Chirality
pub_type: 杂志文章
doi:10.1002/chir.22386
更新日期:2015-01-01 00:00:00
abstract::The racemic title host compound (1) formed homochiral inclusion crystals (conglomerate) of 1 with acetone, while heterochiral inclusion crystals (racemate) were obtained when complexed with ethyl acetate. Upon treatment of the homochiral inclusion crystals of 1 with gaseous acetyl chloride in the solid state, opticall...
journal_title:Chirality
pub_type: 杂志文章
doi:10.1002/chir.20295
更新日期:2006-08-01 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
pub_type: 杂志文章
doi:10.1002/chir.22263
更新日期:2014-01-01 00:00:00
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...
journal_title:Chirality
pub_type: 杂志文章
doi:10.1002/1520-636X(2000)12:8<627::AID-CHIR5>3.0.CO;
更新日期:2000-08-01 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
pub_type: 杂志文章
doi:10.1002/chir.20561
更新日期:2008-07-01 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
pub_type: 杂志文章
doi:10.1002/(SICI)1520-636X(1998)10:8<747::AID-CHIR5>3
更新日期:1998-01-01 00:00:00
abstract::Diastereomeric reduction of nonactivated, hindered β-keto and chiral β-iminoesters are described. The influence of a α-stereocontrolled center on the efficiency and stereoselectivity of the reduction was studied. Reaction conditions were optimized to synthesize β-hydroxy- and β-aminoesters in good yields. In the case ...
journal_title:Chirality
pub_type: 杂志文章
doi:10.1002/chir.20909
更新日期:2011-03-01 00:00:00
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...
journal_title:Chirality
pub_type: 杂志文章
doi:10.1002/chir.23130
更新日期:2019-11-01 00:00:00
abstract::Studies of xenobiotic disposition in rodents often employ experimental designs using differing routes of administration. In an effort to investigate the effects of route of administration on enantioselective disposition of xenobiotics, a chiral polychlorinated biphenyl (PCB), racemic PCB 136, was administered as a sin...
journal_title:Chirality
pub_type: 杂志文章
doi:10.1002/chir.20342
更新日期:2007-01-01 00:00:00
abstract::A rapid and effective RP-UHPLC-DAD method for enantioseparation of three flavanones, i.e., flavanone, naringenin, and hesperetin, was developed and validated. Chromatographic separation of the analytes was performed using a Chiralpak AD-3R analytical column under reverse phase conditions with methanol as the mobile ph...
journal_title:Chirality
pub_type: 杂志文章
doi:10.1002/chir.22559
更新日期:2016-02-01 00:00:00
abstract::Isophthalic and terephthalic acid monoesters of cyclic nigerosyl-(1→6)-nigerose (CNN), a cyclic tetrasaccharide composed of four d-glucopyranosyl residues connected by alternating α-1,3- and α-1,6-linkages, were synthesized as novel chiral supramolecular sensitizers for enantiodifferentiating photoisomerization of (Z)...
journal_title:Chirality
pub_type: 杂志文章
doi:10.1002/chir.22014
更新日期:2012-11-01 00:00:00
abstract::1,1,1,3,3-pentafluoro-2-(fluoromethoxy)-3-methoxypropane, compound B, is a product obtained in the degradation of the anesthetic Sevoflurane. Enantiopure (+)-B was investigated using vibrational circular dichroism (VCD). Experimental absorption and VCD spectra of (+)-B in CDCl(3) solution in the 2,000-900 cm(-1) regio...
journal_title:Chirality
pub_type: 杂志文章
doi:10.1002/chir.10106
更新日期:2002-08-01 00:00:00
abstract::The binding of the title benzodiazepine enantiomers and its modulation by warfarin and bilirubin were studied by chromatography on human serum albumin (HSA) immobilized on Sepharose 4B, and also by a combination of ultrafiltration and circular dichroism (UF-CD) methods. In the absence of warfarin and bilirubin the bin...
journal_title:Chirality
pub_type: 杂志文章
doi:10.1002/chir.530020307
更新日期:1990-01-01 00:00:00
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...
journal_title:Chirality
pub_type: 杂志文章
doi:10.1002/chir.530010306
更新日期:1989-01-01 00:00:00