N,N-dimethylcarbamyl derivatives of oxazepam.

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：: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

authors： Zhang L,Lin S,Tong Q,Li Y,Wang Y,Li Y,Li B,Yang Y

更新日期：2019-11-01 00:00:00

abstract：:Four racemic esters of (1R*,7aR*)-3,6,7,7a-tetrahydro-1-hydroxy-7a-methyl-1H-inden-5(2H)-one were prepared and subjected to hydrolysis with two types of hydrolases, including alcalase and three lipases. Alcalase and lipase showed opposite enantiopreference on these esters. Based on this result, we developed a gram-sca...

journal_title：Chirality

authors： Lo LC,Chou TC,Shie JJ

更新日期：2004-05-05 00:00:00

abstract：:The effects of temperature on the chiral recognition of cyclic β-amino acid enantiomers on zwitterionic [Chiralpak ZWIX(+) and ZWIX(-)] chiral stationary phases were investigated. Experiments were performed at different mobile phase compositions and under 10°C column temperature increments in the temperature range 10-...

journal_title：Chirality

authors： Ilisz I,Pataj Z,Gecse Z,Szakonyi Z,Fülöp F,Lindner W,Péter A

更新日期：2014-08-01 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：:SCH 56592 is a novel triazole antifungal agent that is active both orally and intravenously in animal models of infection. This compound is in Phase II-III clinical trials for the treatment of systemic fungal infections. SCH 56592 is a single enantiomer with four stereogenic centers; therefore, it was necessary to eva...

journal_title：Chirality

authors： Kim H,Lin CC,Laughlin M,Lovey R,Saksena A,Heimark L,Nomeir AA

更新日期：2000-07-01 00:00:00

abstract：:Experimental hyperlipidemia has shown to decrease cytochrome P450 3A4 and 2C11 expression and to increase liver concentrations and the plasma protein binding of halofantrine (HF) enantiomers. The present study examined the effect of hyperlipidemic (HL) serum on the metabolism of HF enantiomers by primary rat hepatocyt...

journal_title：Chirality

authors： Patel JP,Hamdy DA,El-Kadi AO,Brocks DR

更新日期：2012-07-01 00:00:00

abstract：:Ropivacaine hydrochloride monohydrate (ropivacaine) is a new local anaesthetic agent which is administered exclusively as the (-)-(S)-form. The aim of the study was to determine whether metabolic racemisation of (-)-(S)-ropivacaine occurs. This was tested in man, rat, dog, and sheep after different routes of administr...

journal_title：Chirality

authors： Arvidsson T,Bruce HF,Halldin MM

更新日期：1995-01-01 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：:The attempts of applying chiroptical spectroscopy to supramolecular chirality are reviewed with a focus on vibrational circular dichroism (VCD). Examples were taken from gels, solids, and monolayers formed by low-molecular mass weight chiral gelators. Particular attention was paid to a group of gelators with perfluoro...

journal_title：Chirality

authors： Sato H,Yajima T,Yamagishi A

更新日期：2015-10-01 00:00:00

abstract：:A simple high-yield three-steps route to optically active 4-hydroxymethyl-3-(1H-indolyl)oxazolidin-2-ones from (S)-glycidol is described. The key intermediates (R)-oxiran-2-ylmethyl 1H-indol-4/-5-ylcarbamates are obtained in high yields from (S)-glycidol. These are readily transformed to oxazolidin-2-ones, very intere...

journal_title：Chirality

authors： Chiummiento L,Funicello M,Tramutola F

更新日期：2012-04-01 00:00:00

abstract：:The concentration sensitivity of a racemic drug (chlorpheniramine maleate) in chiral capillary electrophoresis with electrospray ionization – mass spectrometric detection was improved ~500-fold via stacking. Enantiomeric separation was achieved through the use of a neutral chiral pseudostationary phase (2-hydroxpropyl...

journal_title：Chirality

authors： Wuethrich A,Haddad PR,Quirino JP

更新日期：2014-11-01 00:00:00

abstract：:The present work firstly described the enantioseparation and determination of flumequine enantiomers in milk, yogurt, chicken, beef, egg, and honey samples by chiral liquid chromatography-tandem mass spectrometry. The enantioseparation was performed under reversed-phase conditions on a Chiralpak IC column at 20°C. The...

journal_title：Chirality

authors： Li S,Liu B,Xue M,Yu J,Guo X

更新日期：2019-11-01 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：: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：: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：: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：:E-6087 is a nonsteroidal anti-inflammatory compound that selectively inhibits cyclooxygenase-2. Because E-6087 has a chiral center, this compound is a racemic mixture of two stereoisomers, (+)-(R)-E-6087 (E-6231) and (-)-(S)-E-6087 (E-6232). A normal-phase liquid-chromatographic method for the enantioselective determi...

journal_title：Chirality

authors： Salgado L,Encina G,Farran R,Puig S,Martínez L

更新日期：2004-05-15 00:00:00

abstract：:Synthetic pyrethroid insecticides are chiral compounds with multiple asymmetric positions. In this study, isomers of four commonly used pyrethroids were separated at the enantiomeric level by enantioselective high-performance liquid chromatography (HPLC), and differences between enantiomers in aquatic toxicity were ch...

journal_title：Chirality

authors： Liu W,Gan JJ,Qin S

更新日期：2005-01-01 00:00:00

abstract：:The opening of ortho-substituted phenyl oxiranes by borohydrides is described both in aqueous and solid phases. Some remarkable differences in the regioselectivity and inversion of enantioselectivity of oxirane ring-opening are reported. The results obtained are compared with previous studies and have allowed some fac...

journal_title：Chirality

authors： Doussot J,Guy A,Siaugue JM,Ferroud C,Guieres AF

更新日期：1999-01-01 00:00:00

abstract：:Rabeprazole is an effective proton pump inhibitor to treat acid-related diseases. To achieve the simultaneous determination of rabeprazole enantiomers in human plasma, a chiral LC-MS/MS method was developed and validated. Acetonitrile including 0.1% ammonium were used as protein precipitating agent. Analytes were sepa...

journal_title：Chirality

authors： Sun LN,Shen YW,Ying YW,Li D,Li TF,Zhang XH,Zhao P,Ding L,Wang YQ

更新日期：2018-12-01 00:00:00

abstract：:A series of silica-supported proline-based peptides were synthesized and applied as catalysts for direct asymmetric intermolecular aldol reactions. Among these, a peptide with two L-proline units was found to be the most efficient one for the asymmetric aldol reactions between acetone and aromatic aldehydes. The react...

journal_title：Chirality

authors： Yan J,Wang L

更新日期：2009-04-01 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：: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 epimeric diterpenes (+)-(1S,3E,7E,11S,12S)-verticilla-3,7-dien-12-ol (1), isolated from Bursera suntui, and (+)-(1S,3E,7E,11S,12R)-verticilla-3,7-dien-12-ol (2), isolated from Bursera kerberi, gave the same Wagner-Meerwein rearrangement product (-)-(1E,4Z,8Z,11S,12R)-phomacta-1,(15)4,8-triene (3). The Et2 O:BF3 -i...

journal_title：Chirality

authors： Del Río-Chávez ÁA,García-Gutiérrez HA,Román-Marín LU,Beiza-Granados L,Cerda-García-Rojas CM,Joseph-Nathan P,Hernández-Hernández JD

更新日期：2019-11-01 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：:Parallel kinetic resolution of Evans' phenylglycine derived oxazolidinone using an equimolar combination of quasi-enantiomeric active esters (derived from [D,13C]-labeled 2-phenylpropionic acid) was achieved. The levels of stereocontrol were high, leading to products with predictable configurations. ...

journal_title：Chirality

authors： Coumbarides GS,Dingjan M,Eames J,Flinn A,Northen J

更新日期：2007-05-05 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 chiral discrimination ability of two recently prepared chiral stationary phases (CSP 1 and CSP 2), based on a leucine derived chiral selector, was tested for the enantiomers of dihydropyrimidone (DHPM) derivatives and compared with the commercially available Hyun-leucine CSP 3 and classical Pirkle-leucine CSP 4. B...

journal_title：Chirality

authors： Forjan DM,Gazić I,Vinković V

更新日期：2007-06-01 00:00:00

abstract：:A variety of reactions can be categorized under the global concept of the "interconversion of stereoisomers." Thus, racemization or epimerization can result from inversion of labile chiral centers. From the examples available, some predictive rules are suggested for a chiral center of the type R"R'RC-H undergoing base...

journal_title：Chirality

authors： Testa B,Carrupt PA,Gal J

更新日期：1993-01-01 00:00:00