Conformational equilibria of TADDOL-s in solution investigated by vibrational circular dichroism.

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：:Massarigenin A (1) and papyracillic acids A (2) and B (3) were isolated from the endophytic fungus Microsphaeropsis sp. Their structures were elucidated by multidimensional nuclear magnetic resonance spectroscopy; the structure of massarigenin A (1) was also confirmed by X-ray crystallography. The absolute configurati...

journal_title：Chirality

authors： Hussain H,Ahmed I,Schulz B,Draeger S,Flörke U,Pescitelli G,Krohn K

更新日期：2011-09-01 00:00:00

abstract：:Many drugs contain a chiral centre, or such a centre is introduced during metabolism of the drug in man and in animals. If a single chiral centre is present, the drug will normally exist as a mixture of two enantiomers, of which one may have quite different pharmacologic and/or toxic effects than the other. Chiral dru...

journal_title：Chirality

authors： Coutts RT,Baker GB

更新日期：1989-01-01 00:00:00

abstract：:Caffeic acid-derived polyethers are a class of natural products isolated from the root extracts of comfrey and bugloss, which are endowed with intriguing pharmacological properties as anticancer agents. The synthesis of new polyether derivatives is achieved through ring-opening polymerization of chiral 2,3-disubstitut...

journal_title：Chirality

authors： Tedesco D,Fabini E,Barbakadze V,Merlani M,Zanasi R,Chankvetadze B,Bertucci C

更新日期：2015-12-01 00:00:00

abstract：:Diamino carboxylic acids have recently come to the attention of scientists working in the field of early life and its development. These are the monomers of a hypothetic early form of genetic material, the so-called Peptide Nucleic Acid (PNA) (Nielson et al., Proc Natl Acad Sci USA 2000;97:3868-3871). Since all biopol...

journal_title：Chirality

authors： Bredehöft JH,Breme K,Meierhenrich UJ,Hoffmann SV,Thiemann WH

更新日期：2007-07-01 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

authors： Zhang J,Holmes AE,Sharma A,Brooks NR,Rarig RS,Zubieta J,Canary JW

更新日期：2003-02-01 00:00:00

abstract：:Nine β-aminoketones were synthesized via Mannich reaction when benzaldehyde was condensed with some primary amines and acetophenone. The purified compounds were identified by using spectroscopic methods. The enantiomeric separation of these derivatives was carried out by high-performance liquid chromatography (HPLC) u...

journal_title：Chirality

authors： Addadi K,Sekkoum K,Belboukhari N,Cheriti A,Aboul-Enein HY

更新日期：2015-05-01 00:00:00

abstract：:Gold particles covered with 1,1'-binaphthyl-2,2'-dithiol (BINAS) were prepared. Using size exclusion chromatography, it was possible for the first time to separate the sample into fractions with different sizes and colors. Transmission electron microscopy shows that the particles are very small, in the order of 1 nm o...

journal_title：Chirality

authors： Gautier C,Taras R,Gladiali S,Bürgi T

更新日期：2008-03-01 00:00:00

abstract：:We report the preparative separation of rac-zopiclone using malic acid as the resolving agent. Furthermore, two different methods for the analytical determination of zopiclone enantiomers by HPLC on chiral stationary phases are described. The benzodiazepine receptor binding of the isolated enantiomers was investigated...

journal_title：Chirality

authors： Blaschke G,Hempel G,Müller WE

更新日期：1993-01-01 00:00:00

abstract：:The new linear polyesters, W1278-A, B, and C, were isolated from culture extracts of a freshwater Ascomycete fungus. Their structures were elucidated on the basis of spectroscopic analyses and chemical transformations, with the absolute configuration established by the circular dichroism (CD) method using (R)-(-)-6-hy...

journal_title：Chirality

authors： Schlingmann G,Roll DM

更新日期：2005-01-01 00:00:00

abstract：:The absolute configuration of the acyclic side chain of heptopyranosides and heptofuranosides was determined by exciton coupled CD, employing the strongly fluorescent 2-anthroate chromophore. The usage of this chromophore offers significant improvements over previous chemical and spectroscopic procedures since its int...

journal_title：Chirality

authors： Akritopoulou-Zanze I,Nakanishi K,Stepowska H,Grzeszczyk B,Zamojski A,Berova N

更新日期：1997-01-01 00:00:00

abstract：:We introduce a method to detect the activity of ion channels and pores with circular dichroism (CD) spectroscopy. G-quartets obtained by potassium templated self-assembly of 5'-guanosine monophosphate (GMP) are used as CD probes, the bee-toxin melittin as representative pore and gramicidin A as representative ion chan...

journal_title：Chirality

authors： Hennig A,Matile S

更新日期：2008-09-01 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 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：: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：: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 cyclic alpha-aminophosphonate was found to be a novel organocatalyst for Michael type addition reactions of carbonyl compounds to nitroolefins to afford the corresponding adducts in high enantio- and diastereoselectivities. ...

journal_title：Chirality

authors： Tao Q,Tang G,Lin K,Zhao YF

更新日期：2008-07-01 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：:Asymmetric molecular and supramolecular systems are characterized by: i. the circular dicroism in the angular distribution of valence photoelectrons emitted from randomly oriented chiral molecules by their interaction with circularly polarized VUV light; ii. the different stability and reactivity of diastereomeric agg...

journal_title：Chirality

authors： Giardini A,Paladini A,Catone D,Piccirillo S,Rondino F,Satta M,Filippi A,Speranza M,Turchini S,Zema N

更新日期：2006-08-01 00:00:00

abstract：:Ibuprofen was used to demonstrate that isolated rat hepatocytes offer a suitable in vitro model to investigate the metabolic chiral inversion of anti-inflammatory 2-arylpropionic acids (profens). The inversion of the pharmacologically inactive (-)-(R)-ibuprofen to the active (+)-(S)-ibuprofen was shown to obey apparen...

journal_title：Chirality

authors： Müller S,Mayer JM,Etter JC,Testa B

更新日期：1990-01-01 00:00:00

abstract：:A comparison of the enantiomeric resolution of (+/-)-threo-methylphenidate (MPH) (Ritalin) was achieved on different polysaccharide based chiral stationary phases. The mobile phase used was hexane-ethanol-methanol-trifluoroacetic acid (480:9.75:9.75:0.5, v/v/v/v). Benzoic acid and phenol were used as the mobile phase ...

journal_title：Chirality

authors： Aboul-Enein HY,Ali I

更新日期：2002-01-01 00:00:00

abstract：:Polymorphonuclear neutrophils (PMNs) are short-lived leukocytes that die by apoptosis. Although PMNs are crucial in the defense against infection, they have been implicated in the pathogenesis of tissue injury observed in inflammatory diseases. The induction or prevention of PMN apoptosis is currently discussed as a k...

journal_title：Chirality

authors： Zielińska-Przyjemska M,Główka FK,Klaczyńska J

更新日期：2008-02-01 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：:One- and two-color, mass selected R2PI spectra of the S(1)<--S(0) transitions in the bare (+)-(R)-1-phenyl-1-ethanol (E(R)) and its complexes with different solvent molecules (solv) (-)-(R)-2-butanol (B(R)) or (+)-(S)-2-butanol (B(S)) and (-)-(R)-2-butylamine (A(R)) or (+)-(S)-2-butylamine (A(S)), have been recorded a...

journal_title：Chirality

authors： Giardini Guidoni A,Piccirillo S,Scuderi D,Satta M,Di Palma TM,Speranza M,Filippi A,Paladini A

更新日期：2001-01-01 00:00:00

abstract：:Planar 2(5H)-furanones substituted at C4 with a chiral pyrrolidinyl group show CD spectra which are apparently due to the distortion of the C4-N1 bond of sp2 character from the plane defined by the 2(5H)-furanone ring atoms and/or due to the presence of substituents in the pyrrolidine ring. This is a new, previously n...

journal_title：Chirality

authors： Gawroński J,Gawrońska K,Kwit M,Kacprzak K,Rychlewska U

更新日期：2004-08-01 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：:This work reports confirmation of the experimental assignment of the absolute-handedness chirality of single-walled carbon nanotubes (SWNTs). This was achieved by applying the scanning tunneling microscopy (STM) imaging technique to a supramolecular composite consisting of a metalized porphyrin derivative (nickel-5,15...

journal_title：Chirality

authors： Abd El-Mageed AIA,Ogawa T

更新日期：2020-03-01 00:00:00

abstract：:Cyclodextrins that are indiscriminately carboxymethylated at the 2-, 3-, and 6-positions are used as chiral NMR solvating agents for cationic substrates with phenyl, naphthyl, pyridyl, indoline, and indole rings. Enantiodifferentiation with the alpha-, beta-, and gamma-cyclodextrin derivatives is compared. The carboxy...

journal_title：Chirality

authors： Provencher KA,Weber MA,Randall LA,Cunningham PR,Dignam CF,Wenzel TJ

更新日期：2010-03-01 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：:Efficient synthesis of several new atropisomeric amino alcohols having 1-phenyl-1H-pyrrole skeleton are reported. Steric arrangements of the products were confirmed by a single-crystal X-ray measurement. The consequences of the size of the N-substituents on enantioinduction were examined by employing the enantioselect...

journal_title：Chirality

authors： Faigl F,Deák S,Erdélyi Z,Holczbauer T,Czugler M,Nyerges M,Mátravölgyi B

更新日期：2015-03-01 00:00:00