Synthesis of novel chiral metal complexes derived from chiral thiosemicarbazide ligands as potential antioxidant agents.

abstract：:The resolution methods applying (-)-(4R,5R)-4,5-bis(diphenylhydroxymethyl)-2,2-dimethyldioxolane ("TADDOL"), (-)-(2R,3R)-α,α,α',α'-tetraphenyl-1,4-dioxaspiro[4.5]decan-2,3-dimethanol ("spiro-TADDOL"), as well as the acidic and neutral Ca(2+) salts of (-)-O,O'-dibenzoyl- and (-)-O,O'-di-p-toluoyl-(2R,3R)-tartaric acid ...

journal_title：Chirality

authors： Bagi P,Fekete A,Kállay M,Hessz D,Kubinyi M,Holczbauer T,Czugler M,Fogassy E,Keglevich G

更新日期：2014-03-01 00:00:00

abstract：:In modern chromatography, chiral stationary phase (CSP) and enantiomer self-disproportionation (ESD) are new inventions of packing material offer a guarantee for a successful enantiomeric separation. All CSPs were synthesized by chemical bonding of the relevant organic moieties onto a porous parent silica material for...

journal_title：Chirality

authors： Mayani VJ,Abdi SH,Mayani SV,Kim HC,Park SK

更新日期：2011-04-01 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：:We have previously shown that (RS)-2-amino-2-(5-tert-butyl-3-hydroxyisoxazol-4-yl)acetic acid (ATAA) is an antagonist at N-methyl-D-aspartic acid (NMDA) and (RS)-2-amino-3-(3-hydroxy-5-methylisoxazol-4-yl)propionic acid (AMPA) receptors. We have now resolved ATAA via diastereomeric salt formation using N-BOC protected...

journal_title：Chirality

authors： Johansen TN,Frydenvang K,Ebert B,Madsen U,Krogsgaard-Larsen P

更新日期：1997-01-01 00:00:00

abstract：:Flurbiprofen is a kind of nonsteroidal anti-inflammatory drug, which has been widely used in clinic for treatment of rheumatoid arthritis and osteoarthritis. It has been reported that S-flurbiprofen shows good performance on clinic anti-inflammatory treatment, while R-enantiomer almost has no pharmacological activitie...

journal_title：Chirality

authors： Cui X,Ding Q,Shan RN,He CH,Wu KJ

更新日期：2019-06-01 00:00:00

abstract：:A series of 1,4-disubstituted piperazine derivatives with hypnotic activity were examined on three polysaccharide-based chiral stationary phases, namely, Chiracel OD, Chiracel OJ and Chiralpak AD. It was possible to resolve all the compounds on all the phases examined (1.13

journal_title：Chirality

authors： Chilmonczyk Z,Ksycinska H,Mazgajska M,Aboul-Enein HY

更新日期：1999-01-01 00:00:00

abstract：:Origin(s) of biological chirality appear(s) to be intimately connected to origin(s) of life. Prebiotic evolution toward these important turning points can be traced back to single chiral molecules. These can be small (monomeric) units as amino acids or monosaccharides or oligomers as oligo-RNA type molecules. Earlier ...

journal_title：Chirality

authors： Caglioti L,Micskei K,Pályi G

更新日期：2011-01-01 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：:Subcellular fractions of three human brain specimens were found to contain esterase activities which hydrolyzed racemic oxazepam 3-acetate (rac-OXA). All three human brain preparations were highly selective toward the S-enantiomer of rac-OXA. ...

journal_title：Chirality

authors： Yang SK,Huang A,Huang JD

更新日期：1993-01-01 00:00:00

abstract：:Three β-keto sulfoxides (1-3) were synthesized in enantiopure form and investigated by means of circular dichroism (CD) spectroscopy, both in electronic and vibrational range (ECD, VCD), in combination with quantum chemical calculations. For compound 2, the X-ray structure was available; thus, the ECD in the solid sta...

journal_title：Chirality

authors： Górecki M,Capozzi MAM,Albano G,Cardellicchio C,Di Bari L,Pescitelli G

更新日期：2018-01-01 00:00:00

abstract：:Analogs of the opioid peptide [D-Ala8]dynorphin A-(1-11)NH2 containing optically pure (R)- and (S)-2-aminotetralin-2-carboxylic acid (Atc) in position 4 were synthesized and evaluated for opioid receptor affinity. These peptides are the first reported dynorphin A analogs containing a conformationally constrained amino...

journal_title：Chirality

authors： Aldrich JV,Zheng QI,Murray TF

更新日期：2001-01-01 00:00:00

abstract：:Chirality is often glossed over in theoretical or experimental discussions concerning the origin of life, but the ubiquity of homochiral building blocks in known biological systems demands explanation. Information theory can provide a quantitative framework for understanding the role of chirality in biology. Here I sh...

journal_title：Chirality

authors： Carroll JD

更新日期：2009-03-01 00:00:00

abstract：:The application of the Cartesian coordinate tensor transfer (CCT) technique for simulations of the IR absorption and vibrational circular dichroism (VCD) spectra of relatively large nucleic acid fragments is demonstrated on several case studies. The approach is based on direct ab initio calculations of atomic tensors,...

journal_title：Chirality

authors： Andrushchenko V,Bouř P

更新日期：2010-01-01 00:00:00

abstract：:A method for the determination of (R)- and (S)-atenolol in human plasma and urine is described. The enantiomers of atenolol are extracted into dichloromethane containing 3% heptafluorobutanol followed by acetylation with acetic anhydride at 60 degrees C for 2 h. The acetylated enantiomers were separated on a chiral al...

journal_title：Chirality

authors： Enquist M,Hermansson J

更新日期：1989-01-01 00:00:00

abstract：:The racemic title host compound (1) formed homochiral inclusion crystals (conglomerate) of 1 with acetone, while heterochiral inclusion crystals (racemate) were obtained when complexed with ethyl acetate. Upon treatment of the homochiral inclusion crystals of 1 with gaseous acetyl chloride in the solid state, opticall...

journal_title：Chirality

authors： Tanaka K,Iwamoto T,Wada S,Frelek J,Caira MR

更新日期：2006-08-01 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：: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：:The influence of latent heat dissipated by the crystallization of 1,1'-binaphthyl in its supercooled molten state on the chiral symmetry breaking transition was investigated. Temperature change in the crystallization system was monitored by infrared thermocamera. Temperature rise due to the dissipation of latent heat ...

journal_title：Chirality

authors： Asakura K,Hayashi M,Osanai S

更新日期：2003-03-01 00:00:00

abstract：:The two enantiomers of 2,2'-bioxirane were synthesized, and their chiroptical properties were thoroughly investigated in various solvents by polarimetry, vibrational circular dichroism (VCD), and Raman optical activity (ROA). Density functional theory (DFT) calculations at the B3LYP/aug-cc-pVTZ level revealed the pres...

journal_title：Chirality

authors： Daugey N,De Rycke N,Brotin T,Buffeteau T

更新日期：2018-04-01 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：: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：:The versatility of a previously developed method for the synthesis of chiral carbene-based palladacycles is demonstrated through the synthesis of two new chiral pyridine-functionalized N-heterocyclic carbene palladacycles with different wingtip groups. The efficiency in their resolution with different counter anions a...

journal_title：Chirality

authors： Ng KH,Li Y,Tan WX,Chiang M,Pullarkat SA

更新日期：2013-03-01 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 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：: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 stability of Chiralpak AD chiral stationary phase under various solvent conditions was investigated. An analytical method for the detection of the presence of solubilized Chiralpak AD coating was developed using CD spectroscopy (CD signal at 245 nm). In addition, NMR analysis of the solubilized polymer revealed a ...

journal_title：Chirality

authors： Welch CJ,Fairchild J,Sajonz P

更新日期：2007-08-01 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：:Isophthalic and terephthalic acid monoesters of cyclic nigerosyl-(1→6)-nigerose (CNN), a cyclic tetrasaccharide composed of four d-glucopyranosyl residues connected by alternating α-1,3- and α-1,6-linkages, were synthesized as novel chiral supramolecular sensitizers for enantiodifferentiating photoisomerization of (Z)...

journal_title：Chirality

authors： Yang C,Liang W,Nishijima M,Fukuhara G,Mori T,Hiramatsu H,Dan-oh Y,Tsujimoto K,Inoue Y

更新日期：2012-11-01 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：:(+/-)-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