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991.
Structure‐Based Design and Synthesis of a Small Molecule that Exhibits Anti‐inflammatory Activity by Inhibition of MyD88‐mediated Signaling to Bacterial Toxin Exposure 下载免费PDF全文
Shahabuddin Alam Sacha Javor Melissa Degardin Dariush Ajami Mitra Rebek Teri L. Kissner David M. Waag Julius Rebek Jr Kamal U. Saikh 《Chemical biology & drug design》2015,86(2):200-209
Both Gram‐positive and Gram‐negative pathogens or pathogen‐derived components, such as staphylococcal enterotoxins (SEs) and endotoxin (LPS) exposure, activate MyD88‐mediated pro‐inflammatory cellular immunity for host defense. However, dysregulated MyD88‐mediated signaling triggers exaggerated immune response that often leads to toxic shock and death. Previously, we reported a small molecule compound 1 mimicking BB‐loop structure of MyD88 was capable of inhibiting pro‐inflammatory response to SEB exposure in mice. In this study, we designed a dimeric structure compound 4210 covalently linked with compound 1 by a non‐polar cyclohexane linker which strongly inhibited the production of pro‐inflammatory cytokines in human primary cells to SEB (IC50 1–50 μm ) or LPS extracted from Francisella tularensis, Escherichia coli, or Burkholderia mallei (IC50 10–200 μm ). Consistent with cytokine inhibition, in a ligand‐induced cell‐based reporter assay, compound 4210 inhibited Burkholderia mallei or LPS‐induced MyD88‐mediated NF‐kB‐dependent expression of reporter activity (IC50 10–30 μm ). Furthermore, results from a newly expressed MyD88 revealed that 4210 inhibited MyD88 dimer formation which is critical for pro‐inflammatory signaling. Importantly, a single administration of compound 4210 in mice showed complete protection from lethal toxin challenge. Collectively, these results demonstrated that compound 4210 inhibits toxin‐induced inflated pro‐inflammatory immune signaling, thus displays a potential bacterial toxin therapeutic. 相似文献
992.
Aldose reductase (ALR) enzyme plays a significant role in conversion of excess amount of glucose into sorbitol in diabetic condition, inhibitors of which decrease the secondary complication of diabetes mellitus. To understand the structural interaction of inhibitors with ALR enzyme and develop more effective ALR inhibitors, a series of substituted 5-phenylbenzoate containing N-substituted rhodanine derivatives were synthesized and evaluated for their in vitro ALR inhibitory activity. Docking studies of these compounds were carried out, which revealed that the 5-phenylbenzoate moiety deeply influenced the key π-π stacking while 4-oxo-2-thioxothiazolidines contributed in hydrogen bond interactions. The phenyl ring of benzylidene system occupied in specific pocket constituted from Phe115, Phe122, Leu300 and Cys303 while the rhodanine ring forms a tight net of hydrogen bond with Val47 at anionic binding site of the enzyme. The structural insights obtained from the docking study gave better understanding of rhodanine and macromolecular interaction and will help us in further designing and improving of ALR inhibitory activity of rhodanine analogs. 相似文献
993.
Synthesis of 5,6‐dihydro‐4H‐benzo[d]isoxazol‐7‐one and 5,6‐dihydro‐4H‐isoxazolo[5,4‐c]pyridin‐7‐one Derivatives as Potential Hsp90 Inhibitors 下载免费PDF全文
Loana Musso Raffaella Cincinelli Giuseppe Giannini Fabrizio Manetti Sabrina Dallavalle 《Chemical biology & drug design》2015,86(5):1030-1035
A novel class of 5,6‐dihydro‐4H‐benzo[d]isoxazol‐7‐ones and 5,6‐dihydro‐4H‐isoxazolo[5,4‐c]pyridin‐7‐ones was designed, synthesized, and assayed to investigate the affinity toward Hsp90 protein. The synthetic route was based on a 1,3‐dipolar cycloaddition of nitriloxides, generated in situ from suitable benzaldoximes, with 2‐bromocyclohex‐2‐enones or 3‐bromo‐5,6‐dihydro‐1H‐pyridin‐2‐ones. Whereas all the compounds bearing a benzamide group on the bicyclic scaffold were devoid of activity, the derivatives carrying a resorcinol‐like fragment showed a remarkable inhibitory effect on Hsp90. Docking calculations were performed to investigate the orientation of the new compounds within the binding site of the enzyme. 相似文献
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995.
Comparative Analysis of Pharmacophore Features and Quantitative Structure–Activity Relationships for CD38 Covalent and Non‐covalent Inhibitors 下载免费PDF全文
Shuang Zhang Xiwen Xue Liangren Zhang Lihe Zhang Zhenming Liu 《Chemical biology & drug design》2015,86(6):1411-1424
In the past decade, the discovery, synthesis, and evaluation for hundreds of CD38 covalent and non‐covalent inhibitors has been reported sequentially by our group and partners; however, a systematic structure‐based guidance is still lacking for rational design of CD38 inhibitor. Here, we carried out a comparative analysis of pharmacophore features and quantitative structure–activity relationships for CD38 inhibitors. The results uncover that the essential interactions between key residues and covalent/non‐covalent CD38 inhibitors include (i) hydrogen bond and hydrophobic interactions with residues Glu226 and Trp125, (ii) electrostatic or hydrogen bond interaction with the positively charged residue Arg127 region, and (iii) the hydrophobic interaction with residue Trp189. For covalent inhibitors, besides the covalent effect with residue Glu226, the electrostatic interaction with residue Arg127 is also necessary, while another hydrogen/non‐bonded interaction with residues Trp125 and Trp189 can also be detected. By means of the SYBYL multifit alignment function, the best CoMFA and CoMSIA with CD38 covalent inhibitors presented cross‐validated correlation coefficient values (q2) of 0.564 and 0.571, and non‐cross‐validated values (r2) of 0.967 and 0.971, respectively. The CD38 non‐covalent inhibitors can be classified into five groups according to their chemical scaffolds, and the residues Glu226, Trp189, and Trp125 are indispensable for those non‐covalent inhibitors binding to CD38, while the residues Ser126, Arg127, Asp155, Thr221, and Phe222 are also important. The best CoMFA and CoMSIA with the F12 analogues presented cross‐validated correlation coefficient values (q2) of 0.469 and 0.454, and non‐cross‐validated values (r2) of 0.814 and 0.819, respectively. 相似文献
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999.
Identification of a major metabolite of danshensu in rat urine and simultaneous determination of danshensu and its metabolite in plasma: application to a pharmacokinetic study in rats 下载免费PDF全文
Xiangyang Wang Wei Li Xiaohui Ma Kaijing Yan Yang Chu Min Han Shuming Li Hongchao Zhang Shuiping Zhou Yonghong Zhu He Sun Changxiao Liu 《Drug testing and analysis》2015,7(8):727-736
Danshensu, as the effective component of Salvia miltiorrhiza (Danshen), has been widely used in clinical studies for treatment of cardiovascular diseases in China. A new metabolite, 4‐hydroxy‐3‐methoxyphenyllactic acid was isolated from the urine of rats, and its chemical structure was identified by ultraviolet (UV), Infrared Spectroscopy (IR), mass spectrometry (MS) and nuclear magnetic resonance (NMR). Furthermore, a selective and sensitive high performance liquid chromatography‐tandem mass spectrometric (HPLC‐MS/MS) method was developed for the simultaneous quantification of danshensu and its major metabolite, 4‐hydroxy‐3‐methoxyphenyllactic acid, in rat plasma after oral and intravenous administration of danshensu. The separation was performed on a Hypersil Gold C18 column (150 × 2.1 mm i.d., 3.0 µm, Thermo, San jose CA, USA) with gradient elution using a mobile phase composed of methanol and water (containing 0.1% formic acid) at a flow rate of 0.2 mL/min. Linear detection responses were obtained for danshensu and 4‐hydroxy‐3‐methoxyphenyllactic acid ranging from 5 to 10000 ng/mL and 5 to 4000 ng/mL, respectively. The lower limits of quantification (LLOQs) for the two compounds were both 5 ng/mL. The intra‐and inter‐day precision (R.S.D %) were within 5.61% for the two analytes. The average recoveries of the analytes were greater than 72.43%. The method was proved to be stable during all sample storage, preparation and analytic procedures. This method was successfully applied to the pharmacokinetic studies of danshensu and 4‐hydroxy‐3‐methoxyphenyllactic acid after oral and intravenous administration of danshensu in rats.Copyright © 2014 John Wiley & Sons, Ltd. 相似文献