Enantioselective reduction of ketones with borane catalyzed by tridentate amino alcohols derived from salicylaldehyde.

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：: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：:(+/-)-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：: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 first direct asymmetric synthetic preparation of trifluoro-1-(indol-3-yl)ethanols (TFIEs) is described by an enantioselective organocatalytic method from indoles and inexpensive trifluoroacetaldehyde methyl hemiacetal. The reaction is catalyzed by hydroquinine to produce TFIEs in an almost quantitative yield and w...

journal_title：Chirality

authors： Borkin DA,Landge SM,Török B

更新日期：2011-09-01 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：:Here, we report the general strategies by which NMR spectroscopy can be used to determine the enantiopurity and absolute configuration of chalcogen containing secondary alcohols, including the evaluation of the use of chiral solvating and chiral derivatizing agents. The BINOL/DMAP ternary complex demonstrated a simple...

journal_title：Chirality

authors： Marques NBG,Jacob RG,Perin G,Lenardão EJ,Alves D,Silva MS

更新日期：2019-01-01 00:00:00

abstract：:Patterning of solid surfaces with functional organic molecules has been a convenient route to fabricate two-dimensional materials with programmed architecture and activities. One example is the chiral nanoporous networks that can be created via controlled self-assembly of star-shaped molecules under 2D confinement. In...

journal_title：Chirality

authors： Kasperski A,Szabelski P

更新日期：2015-07-01 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：:Herein, we present the solution-state NMR studies on dextromethorphan (1) under both isotropic and anisotropic conditions. From the measurement of 22 residual dipolar couplings using a stretched polystyrene gel (PS), we show that accurate and detailed structural information is readily determined including the relative...

journal_title：Chirality

authors： Swarbrick JD,Ashton TD

更新日期：2010-01-01 00:00:00

abstract：:Racemic 1-phenylethylamine was optically resolved by its own derivative formed with glutaric acid namely (+)-(R)-N-(1-phenylethyl)glutaramic acid. The amide acid resolving agent was synthesized from (+)-(R)-1-phenylethylamine by N-derivatization. The glutaric acid derivative was the next in a homologous series of dica...

journal_title：Chirality

authors： Schindler J,Egressy M,Bereczki L,Pokol G,Fogassy E,Marthi K

更新日期：2007-03-01 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：:In this work, a new capillary electrokinetic chromatography (EKC) approach using ethanediamine-bonded poly (glycidyl methacrylate) (Ami-PGMA) microspheres as pseudostationary phases (PSPs) for enantioseparation with a polysaccharide, chondroitin sulfate E (CSE), as the chiral selector. The CSE@Ami-PGMA EKC system was ...

journal_title：Chirality

authors： Sun X,Yu T,Xu G,Du Y,Chen J,Li X

更新日期：2019-02-01 00:00:00

abstract：:A simple and reliable chiral HPLC method was developed for the determination of enantiomeric excess of a chiral dihydroxy intermediate for the chemoenzymatic synthesis of side chain of statin drugs. After evaluating different columns and conditions, the four stereoisomers of ethyl 3,5-dihydroxy-6-benzyloxy hexanoate w...

journal_title：Chirality

authors： Liu JH,Yu BY,Chen YJ

更新日期：2008-01-01 00:00:00

abstract：:Midodrine hydrochloride is a peripheral alpha(1)-adrenoreceptor agonist that induces venous and arterial vasoconstriction. Midodrine, after oral or intravenous administration, undergoes enzymatic hydrolysis and releases deglymidodrine, a pharmacologically active metabolite. Midodrine and deglymidodrine have a chiral c...

journal_title：Chirality

authors： Quaglia MG,Farina A,Palmery M,Desideri N,Donati E,Bossù E,Strano S

更新日期：2004-07-01 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：:In this review article we examine state-of-the-art techniques for the structural elucidation of organic compounds isolated from natural sources. In particular, we focus on the determination of absolute configuration (AC), perhaps the most challenging but inevitable step in the whole process, especially when newly isol...

journal_title：Chirality

authors： Pescitelli G,Kurtán T,Flörke U,Krohn K

更新日期：2009-01-01 00:00:00

abstract：:In order to get further insight into the mechanism by which bovine serum albumin (BSA) discriminates between enantiomers of organic acids, some radioisotopically labeled, nonaromatic carboxylic acids were studied under varying mobile phase conditions. It was found for a series of N-alkanoyl-DL-[3H]leucines that the D-...

journal_title：Chirality

authors： Allenmark S

更新日期：1993-01-01 00:00:00

abstract：:A chiral liquid chromatography/mass spectrometry (LC/MS) bioanalytical procedure has been developed for the analysis of the antimalaric agent Fenozan B07 in dog plasma. Normal-phase chromatography involving a phenylcarbamate derivative of cellulose coated on silica gel as the chiral stationary phase was used to resolv...

journal_title：Chirality

authors： Maraschiello C,Vilageliu J,Dorronsoro I,Martinez A,Floriano P,Gómez-Acebo E

更新日期：2006-05-15 00:00:00

abstract：:Separations of six dihydropyridine enantiomers on three commercially available cellulose-based chiral stationary phases (Chiralcel OD-RH, Chiralpak IB, and Chiralpak IC) were evaluated with high-performance liquid chromatography (HPLC). The best enantioseparation of the six chiral drugs was obtained with a Chiralpak I...

journal_title：Chirality

authors： Yu J,Tang J,Yuan X,Guo X,Zhao L

更新日期：2017-03-01 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 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 UV absorption and electronic circular dichroism (ECD) spectra of (R)- and (S)-nicotine and (S)-nornicotine in aqueous solution were measured to a significantly lower wavelength range than previously reported, allowing the identification of four previously unobserved electronic transitions. The ECD spectra of the t...

journal_title：Chirality

authors： Clayton PM,Vas CA,Bui TT,Drake AF,McAdam K

更新日期：2013-05-01 00:00:00

abstract：:Two new chiral thiosemicarbazide ligands and their Cu (II), Ni (II), Pd (II), and Zn (II) complexes were synthesized and characterized by nuclear magnetic resonance (NMR) (only for ligand), Fourier transform infrared (FT-IR), ultraviolet visible (UV-Vis), mass, and elemental analysis. The antioxidant activity of ligan...

journal_title：Chirality

authors： Başaran E,Sıcak Y,Sogukomerogullari HG,Karaküçük-Iyidoğan A,Oruç-Emre EE,Sönmez M,Öztürk M

更新日期：2019-06-01 00:00:00

abstract：:Experimental studies suggest that amide bond may significantly deviate from planar arrangement even in linear peptides and proteins. In order to find out the extent to which such deviation may influence principal amide spectroscopic properties, we conducted a computational study of nonplanar N-methylacetamide (NMA) co...

journal_title：Chirality

authors： Bednárová L,Malon P,Bour P

更新日期：2007-11-01 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：:A simple one-dimensional (13)C NMR method is presented to discriminate between stereoisomers of organic compounds with more than one chiral center. By means of this method it is possible to discriminate between all eight stereoisomers of α-tocopherol. To achieve this the chiral solvating agent (S)-(+)-1-(9-anthryl)-2,...

journal_title：Chirality

authors： Lankhorst PP,Netscher T,Duchateau AL

更新日期：2015-11-01 00:00:00

abstract：:The aim of our study was to synthesize vinylic and pyrido-fused pyridazines with a spirano moiety and to investigate their stereochemistry by spectroscopic and HPLC analyses. The vinylic compounds 5 were obtained by Knoevenagel condensation of cyclohexylidene malonates 1 with pyridazinecarbaldehyde 2. Compound 5b exhi...

journal_title：Chirality

authors： Beke G,Gergely A,Szász G,Szentesi A,Nyitray J,Barabás O,Harmath V,Mátyus P

更新日期：2002-05-15 00:00:00

abstract：:Enantiomers of chiral aliphatic hydrocarbons are generally difficult to separate because they lack functional groups to be derivatized in order to generate diastereomers. The systematic and quantitative separation of a series of branched hydrocarbon enantiomers using a chiral cyclodextrin stationary phase and a cryost...

journal_title：Chirality

authors： Meierhenrich UJ,Nguyen MJ,Barbier B,Brack A,Thiemann WH

更新日期：2003-01-01 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