A new definition of life.

abstract：:Little is known about the stereochemistry of sulfation of chiral phenolic drugs. In this study we examined several in vitro approaches to this question, using (+)-, (-)-, or (+/-)-terbutaline as the substrate and the rat liver cytosol as the phenolsulfotransferase enzyme source. The cosubstrate PAPS was either generat...

journal_title：Chirality

authors： Walle UK,Walle T

更新日期：1989-01-01 00:00:00

abstract：:(R)-(+) and (S)-(-)-1-phenylethylamine have been shown to promote highly diastereoselective and complementary enantioselective formal [3 + 2]carbocyclization reactions between 2,3-butanedione and conjugated nitroalkenes with formation of enantiomerically rich 2-hydroxy-3-nitrocyclopentanone derivatives. The reactions ...

journal_title：Chirality

authors： Felluga F,Forzato C,Nitti P,Pitacco G,Prati F,Valentin E,Zangrando E

更新日期：2012-12-01 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：: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：: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：: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：:The macrocyclic glycopeptide, ristocetin A, was covalently bonded to a silica gel support and evaluated as a liquid chromatographic (LC) chiral stationary phase (CSP). Over 230 racemates were resolved in either the reversed-phase mode, the normal-phase mode, or the polar-organic mode. The retention behavior and select...

journal_title：Chirality

authors： Ekborg-Ott KH,Liu Y,Armstrong DW

更新日期：1998-01-01 00:00:00

abstract：:Several biologically active compounds structurally include the enantiopure 2-substituted-1,4-benzodioxane scaffold. The straightforward racemization that affects reactions involving most of the common chemical reactives is thus a crucial issue. The developing of a completely stereo-controlled synthetic route that does...

journal_title：Chirality

authors： Straniero V,Casiraghi A,Fumagalli L,Valoti E

更新日期：2018-07-01 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：: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：:About 30% of a chemically diverse set of compounds were found to separate on four polysaccharide chiral stationary phases using polar organic mobile phases. No structural features appeared to correlate to successful separations. Titrations between normal and polar organic mobile phases suggested that separation mechan...

journal_title：Chirality

authors： Lynam KG,Stringham RW

更新日期：2006-01-01 00:00:00

abstract：:Supercritical fluid chromatography (SFC) is already used for enantioseparation in the pharmaceutical industry, but it is rarely used for the separation of chiral pesticides. Comparing with high performence liquid chromatography, SFC uses much more environmnetal friendly and economic mobile phase, supercritical CO2 . I...

journal_title：Chirality

authors： Zhao L,Xie J,Guo F,Liu K

更新日期：2018-05-01 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：: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：:Two diastereomeric cationic surfactants derived from L-proline, in which the second chiral center is a quaternary nitrogen, have been separated and fully characterized. The recognition properties of the aggregates formed by the two diastereomeric surfactants have been investigated by circular dichroism and (1)H NMR th...

journal_title：Chirality

authors： Borocci S,Ceccacci F,Galantini L,Mancini G,Monti D,Scipioni A,Venanzi M

更新日期：2003-05-15 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：: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：:The special relationship between France and the polarization of light from the beginning of the 19th century until the present day is reviewed in the lives and works of Étienne Louis Malus, François Arago, Jean-Baptiste Biot, Augustin Fresnel, Louis Pasteur, Frédéric Wallerant, Aimé Cotton, Francis Perrin, and Alain A...

journal_title：Chirality

authors： Kahr B

更新日期：2018-04-01 00:00:00

abstract：:Results achieved by the authors in the synthesis of chiral P,N-phosphite ligands are summarized. Three groups of new chiral P,N-phosphites are discussed, namely, ligands derived from 1,1'-bi-2-naphthol, ligands possessing an acyclic phosphorus center, and P*-chiral ligands derived from (S)-2-anilinomethylpyrrolidine. ...

journal_title：Chirality

authors： Gavrilov KN,Bondarev OG,Korostylev AV,Polosukhin AI,Tsarev VN,Kadilnikov NE,Lyubimov SE,Shiryaev AA,Zheglov SV,Gais HJ,Davankov VA

更新日期：2003-01-01 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：:A summary of selected NMR studies of enantiodiscrimination phenomena regarding the use of quinine-based chiral solvating agents (CSAs) for the determination of the enantiomeric compositions in solution is reported, with explanations of their multireceptorial character offered. ...

journal_title：Chirality

authors： Uccello-Barretta G,Balzano F,Salvadori P

更新日期：2005-01-01 00:00:00

abstract：:The possibility that enantiodiscrimination of bilirubin might be involved in neuronal membrane destabilization, and therefore in bilirubin toxicity, was investigated, by circular dichroism, on model membranes composed of phospholipids. The equilibrium between bilirubin enantiomers is displaced at some extent by the in...

journal_title：Chirality

authors： Bernardini C,D'Arrigo P,Elemento G,Mancini G,Servi S,Sorrenti A

更新日期：2009-01-01 00:00:00

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 too...

journal_title：Chirality

authors： Pieraccini S,Ferrarini A,Spada GP

更新日期：2008-05-15 00:00:00

abstract：:Vibrational circular dichroism (VCD) spectra of (+)-alpha-pinene solutions in carbon tetrachloride have been measured in the range of volume fractions 5-100% (v/v) in the mid-infrared region. The concentration dependence measured was statistically analyzed with the aim of obtaining a reliable correlation between the V...

journal_title：Chirality

authors： Urbanova M,Setnicka V V,Volka K

更新日期：2000-05-01 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：:In the presence of tridentate chiral ligand 4e, 99% e.e. value was obtained by asymmetric reduction of ethyl benzoylacetate with borane in toluene at 25 degrees C. Various ligands and reaction conditions were investigated to develop a reasonable mechanism that explains the experimental outcomes. ...

journal_title：Chirality

authors： Lee DS

更新日期：2007-02-01 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：: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：:Advances in the measurement, calculation, and application of vibrational circular dichroism (VCD) for the determination of absolute configuration are described. The purpose of the review is to provide an up-to-date perspective on the capability of VCD to solve problems of absolute stereochemistry for chiral molecules ...

journal_title：Chirality

authors： Freedman TB,Cao X,Dukor RK,Nafie LA

更新日期：2003-11-01 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