Synthesis and characterization of conformationally rigid chiral pyridine-N-heterocyclic carbene-based palladacycles with an unexpected Pd-N bond cleavage.

abstract：:Searching the 3D structural fragments of organic molecules is challenging because of structural differences between X-ray and theoretically calculated geometries and the conformational flexibility of substituents. The codification program called Conformational Code for Organic Molecules (CCOM) can be used to unambiguo...

journal_title：Chirality

authors： Izumi H,Nafie LA,Dukor RK

更新日期：2016-05-01 00:00:00

abstract：:Despite the fact that several studies have reported the concentrations of various free amino acids in tobacco, their enantiomeric composition is unknown. Both the absolute and enantiomeric compositions of proline, alanine, asparagine, aspartic acid, valine, methionine, leucine,and phenylalanine were determined for thr...

journal_title：Chirality

authors： Kullman JP,Chen X,Armstrong DW

更新日期：1999-01-01 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：: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：:In this work, a new capillary electrokinetic chromatography (EKC) approach using ethanediamine-bonded poly (glycidyl methacrylate) (Ami-PGMA) microspheres as pseudostationary phases (PSPs) for enantioseparation with a polysaccharide, chondroitin sulfate E (CSE), as the chiral selector. The CSE@Ami-PGMA EKC system was ...

journal_title：Chirality

authors： Sun X,Yu T,Xu G,Du Y,Chen J,Li X

更新日期：2019-02-01 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：: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：: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：:The use of four cyclodextrins (three native and one beta-CD derivative) as NMR chiral solvating agents to resolve the enantiomers of (+/-)-cizolirtine, 1, and its chemical precursor (the carbinol, (+/-)-2), was investigated. The best enantiodiscrimination occurred when beta-cyclodextrin was used. ROESY experiments wer...

journal_title：Chirality

authors： Redondo J,Blázquez MA,Torrens A

更新日期：1999-01-01 00:00:00

abstract：:Stereoselective high-performance liquid chromatographic separations of eight sterically constrained cyclic β-amino acid enantiomer pairs were carried out using the newly developed Cinchona alkaloid-based zwitterionic chiral stationary phases Chiralpak ZWIX(+) and ZWIX(-). The effects of the mobile phase composition, t...

journal_title：Chirality

authors： Ilisz I,Gecse Z,Lajkó G,Forró E,Fülöp F,Lindner W,Péter A

更新日期：2015-09-01 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：:This review brings together the past and current methods for synthesizing the classical cucurbit[n]uril (Q[n]), structural variants, and derivatives. Here we refer to the first family of Q[n] as " classical," where the cavity is spheroidal and carry no substituents at any of the equatorial methine carbons or the methy...

journal_title：Chirality

authors： Mandadapu V,Day AI,Ghanem A

更新日期：2014-11-01 00:00:00

abstract：:Cyclic triamides bearing amidino groups at the meta position of the phenyl rings were synthesized, and their conformational properties in the crystal and in solution were examined. Compound exists as a capsule-type dimer of the enantiomers with a bowl-shaped syn conformation in the crystal state. Compound exists mainl...

journal_title：Chirality

authors： Nishiyama S,Urushibara K,Masu H,Azumaya I,Kagechika H,Tanatani A

更新日期：2015-08-01 00:00:00

abstract：:Solid phase extraction (SPE)-chiral separation of the important drugs pheniramine, oxybutynin, cetirizine, and brinzolamide was achieved on the C18 cartridge and AmyCoat (150 x 46 mm) and Chiralpak AD (25 cm x 0.46 cm id) chiral columns in human plasma. Pheniramine, oxybutynin, cetirizine, and brinzolamide were resolv...

journal_title：Chirality

authors： Ali I,Al-Othman ZA,Al-Warthan A,Alam SD,Farooqi JA

更新日期：2014-03-01 00:00:00

abstract：:The synthesis of the eight stereoisomers of muscarine has been efficiently accomplished by utilizing the two enantiomers of lactic esters as starting material. The synthetic strategy is based on a SnCl4-catalyzed addition of allyltrimethylsilane to O-protected lactic aldehydes followed by an iodocyclization process. A...

journal_title：Chirality

authors： De Amici M,Dallanoce C,De Micheli C,Grana E,Dondi G,Ladinsky H,Schiavi G,Zonta F

更新日期：1992-01-01 00:00:00

abstract：:Ion channels are pharmacologic receptors and as such exhibit stereoselective interactions with drugs. Ion channels are conformationally mobile transmembrane proteins existing in a number of open and closed states. Drug interactions with these different states may differ quantitatively and qualitatively. Stereoselectiv...

journal_title：Chirality

authors： Triggle DJ

更新日期：1996-01-01 00:00:00

abstract：:A method is described for the HPLC analysis of oxamniquine enantiomers in liver fraction incubates, using a second-generation alpha 1-acid glycoprotein-based column (Chiral-AGP). Oxamniquine is extracted from the incubation media by liquid-liquid extraction, using diethyl ether. The dried residue is redissolved in elu...

journal_title：Chirality

authors： Noctor TA,Fell AF,Kaye B

更新日期：1990-01-01 00:00:00

abstract：:Enantiomers of chiral aliphatic hydrocarbons are generally difficult to separate because they lack functional groups to be derivatized in order to generate diastereomers. The systematic and quantitative separation of a series of branched hydrocarbon enantiomers using a chiral cyclodextrin stationary phase and a cryost...

journal_title：Chirality

authors： Meierhenrich UJ,Nguyen MJ,Barbier B,Brack A,Thiemann WH

更新日期：2003-01-01 00:00:00

abstract：:A statement has been formulated that chirality is an indispensable inherent property of all material objects, at one level of organization of matter or another. The translation of chirality from one level of material objects to another deserves our attention. The parity violation of weak interactions can be discussed ...

journal_title：Chirality

authors： Davankov V

更新日期：2006-08-01 00:00:00

abstract：:Plasmonic nanoparticles (NPs) adsorbing onto helical bacteria can lead to formation of NP helicoids with micron scale pitch. Associated chiroptical effects can be utilized as bioanalytical tool for bacterial detection and better understanding of the spectral behavior of helical self-assembled structures with different...

journal_title：Chirality

authors： Feng W,Kadiyala U,Yan J,Wang Y,DiRita VJ,VanEpps JS,Kotov NA

更新日期：2020-07-01 00:00:00

abstract：:Chiral discrimination in a racemic mixture of dipalmitoylphosphatidylcholine (DPPC) is induced by a new selector at the water-air interface: L-DPPC is segregated in the condensed phase of a Langmuir monolayer upon interactions with an enantiopure amphiphilic compound. ...

journal_title：Chirality

authors： Caminati G,Cicchi S,Lascialfari L,Brandi A

更新日期：2015-11-01 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：:(+/-)-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 modern chromatography, chiral stationary phase (CSP) and enantiomer self-disproportionation (ESD) are new inventions of packing material offer a guarantee for a successful enantiomeric separation. All CSPs were synthesized by chemical bonding of the relevant organic moieties onto a porous parent silica material for...

journal_title：Chirality

authors： Mayani VJ,Abdi SH,Mayani SV,Kim HC,Park SK

更新日期：2011-04-01 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：:The adsorption of heptahelicene, a helically shaped polyaromatic hydrocarbon (C(30)H(18)), on a Cu(111) surface was studied by means of thermal desorption mass spectrometry (TDMS) and low energy electron diffraction (LEED) at temperatures between 130-1,000 K under ultrahigh vacuum (UHV) conditions. The molecule in the...

journal_title：Chirality

authors： Ernst KH,Kuster Y,Fasel R,Müller M,Ellerbeck U

更新日期：2001-01-01 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 series of 1,4-disubstituted piperazine derivatives with hypnotic activity were examined on three polysaccharide-based chiral stationary phases, namely, Chiracel OD, Chiracel OJ and Chiralpak AD. It was possible to resolve all the compounds on all the phases examined (1.13

journal_title：Chirality

authors： Chilmonczyk Z,Ksycinska H,Mazgajska M,Aboul-Enein HY

更新日期：1999-01-01 00:00:00

abstract：:The present study describes a generic strategy using capillary electrophoretic (CE) method for chiral enantioseparation of anti-Alzheimer drugs, namely, donepezil (DON), rivastigmine (RIV), and antifungal drugs, namely, ketoconazole (KET), Itraconazole (ITR), fluconazole (FLU), and sertaconazole (SRT) in which these d...

journal_title：Chirality

authors： Abdel-Megied AM,Hanafi RS,Aboul-Enein HY

更新日期：2018-02-01 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

authors： Baranowska I,Hejniak J,Magiera S

更新日期：2016-02-01 00:00:00