Vibrational Circular Dichroism (VCD) Reveals Subtle Conformational Aspects and Intermolecular Interactions in the Carnitine Family.

abstract：:This work presents results of methyl 7-oxoabiet-13(14)-en-18-oate (3) self-oxidation with air-oxygen in the presence of various bases such as triethylamine or sodium t-butoxide. While under aerobic conditions, the use of sodium t-butoxide as a base results in the formation of four isomeric alcohols, an addition of tri...

journal_title：Chirality

authors： Masnyk M,Kuśmirek D,Trzybiński D,Frelek J

更新日期：2020-04-01 00:00:00

abstract：:This article describes a very useful extension of an unique column switching technique called "Simulated Moving Columns" (SMC) that was previously reported for chiral high performance liquid chromatography (HPLC) (Zhang and McConnell, Journal of Chromatography A 2004;1028:227-238). SMC uses two or three short chiral c...

journal_title：Chirality

authors： Zhang Y,Dai J,Wang-Iverson DB,Tymiak AA

更新日期：2007-09-01 00:00:00

abstract：:The objective of this brief highlight is to point out the central role of the exciton chirality method to gain insights on the structural basis of the recently achieved ligand gating of synthetic ion channels. This unprecedented ligand gating was achieved with an equally unprecedented transmembrane rigid-rod pi-stack ...

journal_title：Chirality

authors： Sakai N,Talukdar P,Matile S

更新日期：2006-02-01 00:00:00

abstract：:A new colorimetric chiral sensor material consisting of three different functional sites such as chromophore (2,4-dinitrophenylazophenol dye), binding site (crown ether), and chiral barrier (3,3'-diphenyl-1,1'-binaphthyl group) was prepared and applied to the recognition of the two enantiomers of primary amino alcohol...

journal_title：Chirality

authors： Cho EN,Li Y,Kim HJ,Hyun MH

更新日期：2011-04-01 00:00:00

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

authors： Stanley FE,Warner AM,McWilliams KM,Stalcup AM

更新日期：2011-01-01 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：:Benalaxyl (BX), methyl-N-phenylacetyl-N-2,6-xylyl alaninate, is a potent acylanilide fungicide and consist of a pair of enantiomers. The stereoselective metabolism of BX was investigated in rat and rabbit microsomes in vitro. The degradation kinetics and the enantiomer fraction (EF) were determined using normal high-p...

journal_title：Chirality

authors： Zhang P,Zhu W,Dang Z,Shen Z,Xu X,Huang L,Zhou Z

更新日期：2011-02-01 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 modern use of preparative chromatography in pharmaceutical development is illustrated by the case of a recent preclinical candidate from these laboratories. The synthesis of the candidate employed a coupling of two enantiopure intermediates, each of which could be resolved using preparative chiral chromatography. ...

journal_title：Chirality

authors： Leonard WR Jr,Henderson DW,Miller RA,Spencer GA,Sudah OS,Biba M,Welch CJ

更新日期：2007-09-01 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：: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

authors： Wang F,Polavarapu PL,Schurig V,Schmidt R

更新日期：2002-08-01 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：:Racemic ketoconazole (KTZ) was the first orally active azole antifungal agent used in clinical practice and has become widely used in the treatment of mucosal fungal infections associated with AIDS immunosuppression and cancer chemotherapy. However, the use of KTZ has been limited because of adverse drug-drug interact...

journal_title：Chirality

authors： Dilmaghanian S,Gerber JG,Filler SG,Sanchez A,Gal J

更新日期：2004-02-01 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：:The separation methods of the enantiomers of two β-blockers and tryptophan were studied using capillary electrochromatography with heparin covalently as well as non-covalently, bonded onto the capillary inner wall as stationary phase and electrokinetic chromatography with heparin as pseudostationary phase. In the case...

journal_title：Chirality

authors： Liu Y,Sombra LL,Stege PW

更新日期：2018-06-25 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

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

authors： Yang C,Liang W,Nishijima M,Fukuhara G,Mori T,Hiramatsu H,Dan-oh Y,Tsujimoto K,Inoue Y

更新日期：2012-11-01 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：:Fourier transform infrared vibrational circular dichroism (FTIR-VCD) measurements have gone through major advances in the last decade. A major thrust in these advances was to find ways that can minimize the VCD spectral artifacts and obtain the VCD signals at enhanced signal quality. However, all these advances are no...

journal_title：Chirality

authors： Polavarapu PL,Shanmugam G

更新日期：2011-10-01 00:00:00

abstract：:This paper reports the enantioseparation of β-hydroxy-1,2,3-triazole derivatives, which present a broad range of biological properties, by supercritical fluid chromatography (SFC) and high-performance liquid chromatography techniques (HPLC). Polysaccharide-based chiral columns (cellulose and amylose) were used to eval...

journal_title：Chirality

authors： Alvarenga N,Porto ALM,Barreiro JC

更新日期：2018-07-01 00:00:00

abstract：:Although the organocatalytic direct asymmetric Michael reactions of carbonyl compounds to nitroalkenes have been investigated intensely, the Michael reaction of the thioether-based donors remains a rather undeveloped field. This work concerns the asymmetric Michael addition of aryl sulfanyl-propan-2-one to nitroalkene...

journal_title：Chirality

authors： Jiang X,Zhang B,Zhang Y,Lin L,Yan W,Wang R

更新日期：2010-07-01 00:00:00

abstract：:The stability of Chiralpak AD chiral stationary phase under various solvent conditions was investigated. An analytical method for the detection of the presence of solubilized Chiralpak AD coating was developed using CD spectroscopy (CD signal at 245 nm). In addition, NMR analysis of the solubilized polymer revealed a ...

journal_title：Chirality

authors： Welch CJ,Fairchild J,Sajonz P

更新日期：2007-08-01 00:00:00

abstract：:The enantioselective hydrogenation of methyl or ethyl pyruvate over cinchona-platinum catalyst system (Orito's reaction) is one of the most intensively studied heterogeneous catalytic asymmetric hydrogenation reactions. Studies aiming at systematic changes of the chiral template have played a crucial role in creating ...

journal_title：Chirality

authors： Tálas E,Margitfalvi JL

更新日期：2010-01-01 00:00:00

abstract：:The application of the Cartesian coordinate tensor transfer (CCT) technique for simulations of the IR absorption and vibrational circular dichroism (VCD) spectra of relatively large nucleic acid fragments is demonstrated on several case studies. The approach is based on direct ab initio calculations of atomic tensors,...

journal_title：Chirality

authors： Andrushchenko V,Bouř P

更新日期：2010-01-01 00:00:00

abstract：:The influence of latent heat dissipated by the crystallization of 1,1'-binaphthyl in its supercooled molten state on the chiral symmetry breaking transition was investigated. Temperature change in the crystallization system was monitored by infrared thermocamera. Temperature rise due to the dissipation of latent heat ...

journal_title：Chirality

authors： Asakura K,Hayashi M,Osanai S

更新日期：2003-03-01 00:00:00

abstract：:An increase in both retention and enantioselectivity for some beta-blocking agents was observed when exchanging potassium to sodium ion in the buffer used as mobile phase. A large effect of ionic strength on retention was observed, while the enantioselectivity was constant. ...

journal_title：Chirality

authors： Hedeland M,Jönsson S,Isaksson R,Pettersson C

更新日期：1998-01-01 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：:In this review, the recently reported approaches for the preparation of cyclodextrin-functionalized capillary monolithic columns are highlighted, with few applications in chiral separations using capillary liquid chromatography (CLC) and capillary electrochromatography (CEC). Chirality 28:97-109, 2016. © 2015 Wiley Pe...

journal_title：Chirality

authors： Adly FG,Antwi NY,Ghanem A

更新日期：2016-02-01 00:00:00

abstract：:A rapid and simple procedure for enantioselective preparation of 2- and 3-substituted 2,3-dihydro[1,4]dioxino[2,3-b]pyridine derivatives (A and B, respectively) is described. The enantiomeric purity of each isomer was determined by capillary electrophoresis using a dual-cyclodextrin system (S-beta-CD/beta-CD) dissolve...

journal_title：Chirality

authors： Lazar S,Soukri M,El Haddad M,Akssira M,Leger JM,Jarry C,Morin P,Guillaumet G

更新日期：2005-01-01 00:00:00

abstract：:Both epimers of the naturally occurring nonproteinogenic amino acid L-cyclopentenylglycine, (2S,1'S)- and (2S, 1'R)-2-(cyclopent-2'-enyl)glycine, were obtained via a procedure involving condensation of 3-chlorocyclopentene with diethyl acetylaminomalonate, deethoxycarbonylation, chromatographic separation of the resul...

journal_title：Chirality

authors： Andersen L,Nielsen B,Jaroszewski JW

更新日期：2000-10-01 00:00:00