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1.
During the corresponding author's transfer from Dongguk University to Sungkyunkwan University in March 2006, data from the previous University was transferred to the corresponding author's new computer. During this data transfer there was a mixing of EMSA data from experiments involving Quercetin (QC), Ochnaflavone (OC), Tanshinone (TS), Crytotanshinone (CT), BMK, and natural extracts. The mixed EMSA data was inadvertently incorporated in more than one publication. Figure 6 has been corrected to new data with re‐confirmation. J. Cell. Biochem. 108: 337, 2009. © 2009 Wiley‐Liss, Inc.

6. Effect of OC on the TNF‐α‐induced DNA binding activities of MMP‐9, NF‐κB, and AP‐1 motif in HASMC. Cells were pretreated with indicated OC for 40 min in serum‐free medium, were incubated with TNF‐α (100 ng/ml) for 24 h. Nuclear extracts were analyzed by EMSA for the activated NF‐κB (A) and AP‐1 (B) using radiolabeled oligonucleotide probes, respectively. Indicated values are means of three triplicate experiments.  相似文献   


2.
Organocatalytic enantioselective synthesis of α‐indolyl phosphonates has been successfully carried out via asymmetric Friedel‐Crafts alkylation of substituted indoles with (E)‐dialkyl 3‐oxoprop‐1‐enylphosphonates in 48–82% yield and 73–96% ee. Chirality, 2009. © 2008 Wiley‐Liss, Inc.  相似文献   

3.
The reduction of the axially chiral N‐(o‐aryl)‐5,5‐dimethyl‐2,4‐oxazolidinediones by NaBH4 yielded axially chiral N‐(o‐aryl)‐4‐hydroxy‐5,5‐dimethyl‐2‐oxazolidinone enantiomers having a chiral center at C‐4, with 100% diastereoselectivity as has been shown by their 1H and 13C NMR spectra and by enantioselective HPLC analysis. The resolved enantiomeric isomers were found to interconvert thermally through an aldehyde intermediate formed upon ring cleavage via a latent ring‐chain‐ring tautomerization. It was found that the rate of enantiomerization depended on the size and the electronic effect of the ortho substituent present on the aryl ring bonded to the nitrogen of the heterocycle. Chirality 2010. © 2009 Wiley‐Liss, Inc.  相似文献   

4.
The above article from the Journal of Biophotonics, published online on 9 January 2018 in Wiley Online Library as Early View ( https://onlinelibrary.wiley.com/doi/abs/10.1002/jbio.201700354 ), and in Volume 11, e201700354, has been retracted by agreement between the authors (Hong Zhong, Lin Lu, Yuanhao Wang, Hongxing Yang), Prof. Sailing He, Prof. Jurgen Popp (Editor‐in‐Chief) and Wiley‐VCH GmbH & Co. KGaA. The retraction has been agreed because the submitting author Hong Zhong failed to acknowledge the true authorship of the presented study which was originally conducted by a group led by Prof. Sailing He in South China Normal University, Guangzhou of China. REFERENCE Zhong H, Lu L, Wang Y, Yang H. Single layer molybdenum disulfide as an optical nanoprobe for 2 photon luminescence and second harmonic generation cell imaging. J. Biophotonics  2018 ;11:e201700354. https://doi.org/10.1002/jbio.201700354  相似文献   

5.
The above article, published online on 04 July 2018 in Wiley Online Library ( https://doi.org/10.1002/cbin.11029 ), has been withdrawn by agreement with the journal Editor, Sergio Schenkman, and John Wiley & Sons Ltd. The withdrawal has been agreed because the authors have not provided final corrections.  相似文献   

6.
Retraction: Kamath PR, Joseph MM, Ajees AA, et al. Bisindole‐oxadiazole hybrids, T3P mediated synthesis and appraisal of their apoptotic, antimetastatic and computational Bcl‐2 binding potential. J Biochem Mol Toxicol . 2017;31:e21962. https://doi.org/10.1002/jbt.21962 The above article from the Journal of Biochemical and Molecular Toxicology , published online on 19 July 2017 in Wiley Online Library ( https://onlinelibrary.wiley.com/doi/abs/10.1002/jbt.21962 ) and in Volume 31, Issue 11, has been retracted by agreement of the Journal Editor‐in‐Chief, Dr Hari Bhat, and Wiley Periodicals, Inc. The retraction has been agreed due to the absence of access to the original data needed to answer questions about the reliability of some of the findings presented in the paper.  相似文献   

7.
The stereocontrolled synthesis of fully protected (2S,4S,6S)‐2‐amino‐6‐hydroxy‐4‐methyl‐8‐oxodecanoic acid was accomplished using a glutamate derivative as starting material. The key steps of this stereochemical synthetic pathway involved an Evans asymmetric alkylation, a Sharpless asymmetric epoxidation, and a Grignard reaction. Copyright © 2012 European Peptide Society and John Wiley & Sons, Ltd.  相似文献   

8.
In order to assign the absolute configurations of 8‐tert‐butyl‐2‐hydroxy‐7‐methoxy‐8‐methyl‐9‐oxa‐6‐azaspiro[4.5]dec‐6‐en‐10‐one ( 2a , 2b ), their esters ( 5a , 5b , 5c , 5d ) with (R)‐ or (S)‐2‐methoxyphenylacetic acid ( 4a , 4b ) have been synthesized. The absolute configurations of these compounds have been determined on the basis of NOESY correlations between the protons of the tert‐butyl group and the cyclopentane fragment of the molecules. The crucial part of this analysis was assignment of the absolute configuration at C‐5. Additionally, by calculation of the chemical shift anisotropy, δRS, for the relevant protons, it was also possible to confirm the absolute configurations at the C‐2 centres of compounds 2a , 2b and 5a , 5b , 5c , 5d . Chirality, 25:422–426, 2013.© 2013 Wiley Periodicals, Inc.  相似文献   

9.
(S)‐(?)‐1‐(1′‐napthyl)‐ethanol (S‐NE) is an important intermediate for the preparation of mevinic acid analogs, which is used for the treatment of hyperlipidemia. The objectives of the study were to isolate a microorganism that could effectively reduce 1‐acetonaphthone (1‐ACN) to S‐NE, to determine the influence that the physicochemical parameters would have on the reduction by the isolated microorganism, and to attempt large‐scale studies with the microorganism. Over the years fungi have been considered a promising biocatalyst and it has been presumed that many fungal species have not been isolated and therefore the current study focused on possible isolation of these microorganisms. A total of 72 fungal isolates were screened for their ability to reduce 1‐ACN to its corresponding alcohol. The isolate, EBK‐62, identified as Alternaria alternata, was found to be the most successful at reducing the ketone to the corresponding alcohol in the submerged culture. The reaction conditions were systematically optimized for the reducing agent A. alternata EBK62, which showed high stereospecificity and good conversion for the reduction. The preparative scale study was carried out in a 2 L bioreactor and a total of 4.9 g of S‐NE in optically pure form (>99% enantiomeric excess) was produced in 48 h. Chirality 28:669–673, 2016. © 2016 Wiley Periodicals, Inc.  相似文献   

10.
A series of new chiral molecular tweezers, di‐(R,R)‐1‐[10‐(1‐hydroxy‐2,2,2‐trifluoroethyl)‐9‐anthryl]‐2,2,2‐trifluoroethyl phthalate (2), isophthalate (3) and terephthalate (4), were synthesized and their structure studied by NMR and molecular mechanics. Their effectiveness as chiral solvating agents for the determination of the enantiomeric purity of chiral compounds using NMR was demonstrated. Chirality 2010. © 2009 Wiley‐Liss, Inc.  相似文献   

11.
A new set of optically active 2,3,3‐ and 2,7,7‐trimethyl‐substituted γ‐aminonorbornan‐2‐ols have been obtained from 2‐methylenenorbornane‐1‐carbonitriles derived from (+)‐camphor and (?)‐fenchone and probed as chiral ligands for the enantioselective addition of diethylzinc to benzaldehyde. This has allowed the study of the structural factors influencing the chirality transfer, such as variation of the relative configuration at C(2) and steric hindrance at C(2), C(3), and C(7) positions of norbornane, which result in the observance of the important role played by the gem‐dimethyl position in γ‐aminonorbornan‐2‐exo‐ols. An empirical rationalization of the obtained experimental results has been realized on the basis of energetically‐favored diastereomeric Noyori‐like transition states. Chirality 2010. © 2010 Wiley‐Liss, Inc.  相似文献   

12.
Five new diterpenoid alkaloids, tianshanitines A‐E ( 1  –  5 ), along with ten known compounds ( 6  –  15 ), were isolated from the EtOH extracts of the whole plant of Delphinium tianshanicum W.T.Wang . Their structures were determined based on extensive spectroscopic analyses, including 1D‐ and 2D‐NMR, HR‐ESI‐MS, and the structure of tianshanitine C ( 3 ) was confirmed by X‐ray diffraction analysis. Tianshanitine A ( 1 ) is the first example of natural diterpenoid alkaloid containing a benzoyl group at C(1) position. Tianshanitine B ( 2 ) is a rare natural diterpenoid alkaloid bearing a OH group at C(16) position. Compounds 1  –  5 , 6 , 8 , 10 , 12 and 14 were evaluated for cytotoxicity against HCT116, MCF‐7 and HepG2 human cancer cell lines.  相似文献   

13.
An efficient synthetic strategy to 3‐methylidene‐2,3‐dihydroquinolin‐4(1H)‐ones variously substituted in position 2 has been developed. The title compounds were synthesized in the reaction sequence involving reaction of diethyl methylphosphonate with methyl 2‐(tosylamino)benzoate, condensation of thus formed diethyl 2‐oxo‐2‐(2‐N‐tosylphenyl)ethylphosphonate with various aldehydes followed by successful application of the obtained 3‐(diethoxyphosphoryl)‐1,2‐dihydroquinolin‐4‐ols as Horner–Wadsworth–Emmons reagents for the olefination of formaldehyde. Also, enantioselective approach to the target compounds has been evaluated using 3‐dimenthoxyphosphoryl group as a chiral auxiliary. Single X‐ray crystal analysis of (2S)‐3‐(dimenthoxyphosphoryl)‐2‐phenyl‐1‐tosyldihydroquinolin‐4‐ol revealed the presence of strong resonance‐assisted hydrogen bond (RAHB). The obtained 3‐methylidene‐2,3‐dihydroquinolin‐4(1H)‐ones were then tested for their cytotoxic activity against two leukemia cell lines NALM‐6 and HL‐60 and a breast cancer MCF‐7 cell line. All compounds showed very high cytotoxic activity with the IC50 values mostly below 1 μm in all three cancer cell lines. The selected analogs were also tested on human umbilical vein endothelial cells (HUVEC) and on human mammary gland/breast cells (MCF‐10A) to evaluate their influence on normal cells. Since one of the most serious problems in cancer chemotherapy is the development of drug resistance, the mRNA levels and activity of ABCB1 transporter considered to be the most important factor engaged in drug resistance, were evaluated in MCF‐7 cells treated with two selected analogs. Both compounds were strong ABCB1 transporter inhibitors that could prevent efflux of anticancer drugs from cancer cells.  相似文献   

14.
Novel 3‐alkyl‐4,1‐benzoxazepine‐2,5‐diones were synthesized in good ee exploiting the chiral pool methodology, an economical way of asymmetric synthesis. Various anthranilic acids are coupled with different α‐haloacids to afford N‐acylated anthranilic acid intermediates which undergo cyclization to (3R)‐3‐alkyl‐4,1‐benzoxazepines‐2,5‐diones. Chirality 25:865–870, 2013. © 2013 Wiley Periodicals, Inc.  相似文献   

15.
A simple and straightforward four‐step synthesis of novel diastereomeric L‐phenylalanine‐derived pyrazolidin‐3‐ones is described. The absolute configuration of the novel C(5) stereogenic centre has been unambiguously determined by single crystal X‐ray analysis and via chemical interconversions. A series of novel thiourea derived pyrazolidinones have been prepared and tested as potential organocatalysts. N(1) un‐substituted pyrazolidinones can be used for the construction of a novel type of bicyclic heterocycles and other selective derivatizations. Chirality 25:541–555, 2013. © 2013 Wiley Periodicals, Inc.  相似文献   

16.
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 Ca2+ salts of (?)‐O,O'‐dibenzoyl‐ and (?)‐O,O'‐di‐p‐toluoyl‐(2R,3R)‐tartaric acid were extended for the preparation of 1‐n‐butyl‐3‐methyl‐3‐phospholene 1‐oxide in optically active form. In one case, the intermediate diastereomeric complex could be identified by single‐crystal X‐ray analysis. The absolute P‐configuration of the enantiomers of the phospholene oxide was also determined by comparing the experimentally obtained and calculated CD spectra. Chirality 26:174–182, 2014. © 2014 Wiley Periodicals, Inc.  相似文献   

17.
The above article from Cell Proliferation, published online on 18 November 2008 in Wiley Online Library ( wileyonlinelibrary.com ), and in Volume 41, pp. 936‐959, has been retracted by agreement between the Editor in Chief, Dr Catherine Sarraf, and John Wiley and Sons Ltd. The retraction has been agreed upon following the recent confirmation regarding an internal investigation that was conducted by the Institutional Office for Research Integrity (UIR) at the National Institute for Cancer Research, Genova, Italy, in 2009, which found evidence of fabricated/duplicated data within the article.  相似文献   

18.
A sensitive and selective spectrofluorimetric method has been developed for the rapid determination of aluminium. This method is based on the complex formation between aluminium and 2‐hydroxy‐1‐naphthylidene‐(8‐aminoquinoline) (HNAQ). The optimum conditions for the complex formation were a metal‐to‐ligand (M : L) stoichiometric ratio of 1:1, a pH of 5.5 and a 0.20 m acetate buffer. The fluorescence of the complex was monitored at an emission wavelength of 502 nm with excitation at 438 nm. Under these conditions, linear calibration curves were obtained in the ranges 0.05–1 and 1–5 ppm. The detection limit was 3.4 ppb for the former and 13.5 ppb for the latter. The maximum relative standard deviation of the method for an aluminium standard of 200 ppb was 1.5% (n = 5). This method was successfully applied for the determination of aluminium in drinking water, pharmaceutical antacid tablets and suspension samples. Copyright © 2010 John Wiley & Sons, Ltd.  相似文献   

19.
A library of 175 dipeptidomimetics and tripeptidomimetics containing an α‐amino boronic acid or boronate has been synthesized, and the activity toward Mycobacterium tuberculosis, Candida albicans, Staphylococcus aureus, Streptococcus pyogenes, Escherichia coli and Pseudomonas aeruginosa has been screened. Although there is no clear structure–activity relationship, several compounds exhibit promising activity against different pathogens. Copyright © 2013 European Peptide Society and John Wiley & Sons, Ltd.  相似文献   

20.
On‐column reaction gas chromatography combines the power of separation and rapid analysis of reactants and reaction products with screening of reactions in a single step. Not only conversions but the reaction rates at various temperatures can be obtained from single measurements, making this approach superior to the time‐consuming measurements typically performed in reaction progress analysis. However, this approach has only been used in the investigation of interconversion processes, rearrangement reactions, and only a few examples of higher‐order reactions are known. Here we present the screening of immobilized gadolinium(III)‐tris[(1R,4S)‐3‐heptafluorobutanoyl‐camphor] in the Danishefsky‐hetero‐Diels‐Alder‐reaction by enantioselective on‐column reaction gas chromatography utilizing cryogenic focusing to achieve catalytic conversions in this higher‐order reaction and subsequent separation of the enantiomeric product mixture to determine the enantiomeric ratio. The results obtained by this approach could be transferred to the conventional batch reaction at a larger scale, demonstrating that on‐column reaction chromatography provides reliable results in the screening of enantioselective reactions. Chirality 26:243–248, 2014. © 2014 Wiley Periodicals, Inc.  相似文献   

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