Stereospecific pH-dependent degradation kinetics of R- and S-naproxen-beta-l-O-acyl-glucuronide.

abstract：:Methods for the resolution of (+/-)-1-methyl-7-oxabicyclo[2.2.1]heptan-2-one 1, a versatile chiral building block for terpenoids, have been investigated. While no efficient result was obtained with kinetic resolution methods, both enantiomers of 1 were prepared optically pure for the first time via esterification of t...

journal_title：Chirality

authors： Guan YK,Li YL

更新日期：2005-02-01 00:00:00

abstract：:The straightforward synthesis of a series of enantiomerically pure Lewis basic amides by simple condensation of commercially available enantiopure diamines with picolinic acid is reported. These compounds were shown to promote the enantioselective reduction of ketoimines with trichlorosilane. Working with the model su...

journal_title：Chirality

authors： Guizzetti S,Benaglia M,Cozzi F,Rossi S,Celentano G

更新日期：2009-01-01 00:00:00

abstract：:A new water soluble zinc-salophen complex with appended D-glucose moieties was synthesized and characterized. Its binding properties toward six aminoacids were investigated by UV-vis spectrophotometric titrations. Association constants showed to be unfavorably affected by increasing steric hindrance of the side chain....

journal_title：Chirality

authors： Dalla Cort A,De Bernardin P,Schiaffino L

更新日期：2009-01-01 00:00:00

abstract：:We studied the interaction of poly-l-lysine (PLL) and poly-l-arginine (PLAG) with sodium dodecyl sulfate (SDS) surfactant and the interaction of poly-l-glutamic acid (PLGA) and poly-l-aspartic acid (PLAA) with tetradecyltrimethylammonium bromide (TTAB) surfactant using vibrational circular dichroism (VCD) spectroscopy...

journal_title：Chirality

authors： Novotná P,Urbanová M

更新日期：2015-12-01 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：:The enantiomerization and enantioselective bioaccumulation of metalaxyl by a single dose of exposure to Tenebrio molitor larvae under laboratory condition were studied by high-performance liquid chromatography tandem mass spectroscopy (HPLC-MS/MS) based on a ChiralcelOD-3R [cellulosetris-tris-(3, 5-dichlorophenyl-carb...

journal_title：Chirality

authors： Gao Y,Wang H,Qin F,Xu P,Lv X,Li J,Guo B

更新日期：2014-02-01 00:00:00

abstract：:Kynurenic acid (KYNA), an endogenous antagonist of N-methyl-D-aspartate and α(7) nicotinic acetylcholine receptors, is one of the L-tryptophan (Trp) metabolites. To compare the level of KYNA produced in the striatum of rats after independent administration of L-Trp and D-Trp, rats were intraperitoneally administered L...

journal_title：Chirality

authors： Ishii K,Iizuka H,Ogaya T,Song Z,Fukushima T

更新日期：2011-01-01 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：:3alpha,12alpha-dihydroxy-5beta-cholan-24-oic acid (deoxycholic acid DCA) is able to discriminate between the R- and S-enantiomers of camphorquinone and endo-(+)-3-bromocamphor and select only the S-enantiomers from a racemic mixture. DCA forms novel well ordered 1:1 adducts with (1S)-(+)-camphorquinone and (1S)-endo-(...

journal_title：Chirality

authors： Tahir MI,Rees NH,Heyes SJ,Cowley AR,Prout K

更新日期：2008-07-01 00:00:00

abstract：:Bis(diamido)-bridged basket resorcin[4]arene (all-S)-1 and its (all-R)-1 enantiomer proved able to interact with 2'-deoxycytidine (2) and pyrimidine nucleoside analogs in dimethyl sulfoxide (DMSO) solution. In such a solvent, the resorcinarene hosts adopt a preferential 1,3-alternate-like conformation, with a larger c...

journal_title：Chirality

authors： D'Acquarica I,Calcaterra A,Sacco F,Balzano F,Aiello F,Tafi A,Pesci N,Uccello-Barretta G,Botta B

更新日期：2013-12-01 00:00:00

abstract：:The two enantiomers of N-acyl amide and N-ureide derivatives of 3-amino-5-phenyl-1,4-benzodiazepin-2-ones, which have been known to show anti-respiratory syncytial virus (RSV) activity, were resolved on seven different Pirkle-type chiral stationary phases (CSPs) with the use of 10% isopropyl alcohol in hexane as a mob...

journal_title：Chirality

authors： Park JY,Cho HS,Hyun MH

更新日期：2011-01-01 00:00:00

abstract：:A detailed experimental investigation of an aza-Michael reaction of aniline and chalcone is presented. A series of Cinchona alkaloid-derived organocatalysts with different functional groups were prepared and used in the aza-Michael and retro-aza-Michael reaction. There was an interesting finding that a complete revers...

journal_title：Chirality

authors： Cai YF,Li L,Luo MX,Yang KF,Lai GQ,Jiang JX,Xu LW

更新日期：2011-05-01 00:00:00

abstract：:The phenomenon of enantioselectivity in the metabolism of mexiletine (MEX) conjugation was investigated in eight female patients with the arrhythmic form of chronic Chagas' heart disease treated with racemic mexiletine hydrochloride (two 100 mg capsules every 8 hr). Blood samples were collected up to 24 hr after the a...

journal_title：Chirality

authors： Lanchote VL,Cesarino EJ,Santos VJ,Mere Júnior Y,Santos SR

更新日期：1999-01-01 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：:Compound A, a novel disubstituted pyrrolidine acid, is a member of a new class of agents that are potentially useful for the treatment of diabetes and dyslipidemia. The absolute configuration of this compound was determined by using vibrational circular dichroism (VCD). The results are in agreement with the assignment...

journal_title：Chirality

authors： Freedman TB,Cao X,Phillips LM,Cheng PT,Dalterio R,Shu YZ,Zhang H,Zhao N,Shukla RB,Tymiak A,Gozo SK,Nafie LA,Gougoutas JZ

更新日期：2006-09-01 00:00:00

abstract：:An improved synthesis of the enantiomers of the new benzofurane-type antiarrhythmic compound 1 is described, which makes use of the enantiomerically pure mbe-lactol. Thus, acylation of the benzofurane 4 with acetic anhydride and subsequent bromination gave the bromoacetyl-derivative 6, which, after reduction with LiAl...

journal_title：Chirality

authors： Ecker G,Fleischhacker W,Helml T,Noe CR,Scasny S,Lemmens-Gruber R,Studenik C,Marei H,Heistracher P

更新日期：1994-01-01 00:00:00

abstract：:Homoprolinol analogs, a class of optically active γ-amino alcohols, were examined systematically in the enantioselective addition reactions of diethylzinc to aldehydes. By comparison of the results catalyzed by these γ-amino alcohols with those by the β-amino alcohols based on pyrrolidine architecture reported in the ...

journal_title：Chirality

authors： Liu CL,Wei CY,Wang SW,Peng YG

更新日期：2011-11-01 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：:The direct Michael addition reaction of cyclohexanone/aliphatic aldehydes with nitroolefins, catalyzed by a novel chiral pyrrolidine-thiourea catalyst 1a, is described. The desired 1,4-adducts were obtained in moderate yields with enantioselectivities up to 99% ee and dr up to 99:1 of the syn product. ...

journal_title：Chirality

authors： Shen Z,Zhang Y,Jiao C,Li B,Ding J,Zhang Y

更新日期：2007-05-05 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：: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：:The chiral fungicide furametpyr is widely used in the rice field to control rice sheath blight; however, furametpyr enantiomers are treated as just one compound in traditional achiral analysis, which gives only partial information. An effective chiral analytical method was developed for the resolution and determinatio...

journal_title：Chirality

authors： Dong F,Chen X,Xu J,Liu X,Chen Z,Li Y,Zhang H,Zheng Y

更新日期：2013-12-01 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：: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：:A calculation of the circular dichroism (CD) spectra of carbonmonoxy- and deoxy-myoglobin is carried out in relation to a time-resolved CD experiment. This calculation allows us to assign a dominant role to the proximal histidine in the definition of the electronic normal modes and to interpret the transient CD struct...

journal_title：Chirality

authors： Dartigalongue T,Hache F

更新日期：2006-05-05 00:00:00

abstract：:Chiral natural flavor compounds exhibit characteristic enantiomeric excesses due to stereoselective, enzymatically catalyzed reactions during biogenesis. Although the enzymatic formation of the strawberry key flavor compound 4-hydroxy-2,5-dimethyl-3(2H)-furanone (HDMF; Furaneol(R)) is anticipated, the naturally occurr...

journal_title：Chirality

authors： Raab T,Hauck T,Knecht A,Schmitt U,Holzgrabe U,Schwab W

更新日期：2003-08-01 00:00:00

abstract：:The influence of endotoxin-induced inflammation on the enantioselective pharmacokinetics of propranolol, oxprenolol, and verapamil, which bind to alpha 1-acid glycoprotein, was studied in the rat. The racemic mixtures were given orally. In the control animals, for propranolol and oxprenolol, the plasma concentrations ...

journal_title：Chirality

authors： Laethem ME,Belpaire FM,Wijnant P,Rosseel MT,Bogaert MG

更新日期：1994-01-01 00:00:00

abstract：:The gem-disubstituted cyclotriphosphazene 1 reacted with piperazine (pip) to give the piperazine-bridged derivative 2, which is expected to exist in meso and racemic forms because the two PCl (pip) groups are stereogenic. The proton-decoupled (31)P NMR spectrum of 2 gave rise to two similar sets of ABX signals in a 1:...

journal_title：Chirality

authors： Bui TT,Coles SJ,Davies DB,Drake AF,Eaton RJ,Hursthouse MB,Kiliç A,Shaw RA,Yeşilot S

更新日期：2005-10-01 00:00:00

abstract：:C2 -symmetric N,N-bis(phosphinomethyl)amines were prepared by the thermal reaction of aromatic aldehydes with ammonia and hypophosphorus acid as previously described. Both enantiomers of C2 -symmetric N,N-bis(phosphinomethyl)amine were obtained in a high enantiomeric purity through the diastereomeric salt formation wi...

journal_title：Chirality

authors： Kaboudin B,Faghihi MR,Kazemi F,Yokomatsu T

更新日期：2015-01-01 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