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951.
Zhe Liang Viktor Demko Robert C. Wilson Kenneth A. Johnson Rafi Ahmad Pierre‐François Perroud Ralph Quatrano Sen Zhao Kamran Shalchian‐Tabrizi Marisa S. Otegui Odd‐Arne Olsen Wenche Johansen 《The Plant journal : for cell and molecular biology》2013,75(5):742-754
DEK1, the single calpain of land plants, is a member of the ancient membrane bound TML–CysPc–C2L calpain family that dates back 1.5 billion years. Here we show that the CysPc–C2L domains of land plant calpains form a separate sub‐clade in the DEK1 clade of the phylogenetic tree of plants. The charophycean alga Mesostigma viride DEK1‐like gene is clearly divergent from those in land plants, suggesting that a major evolutionary shift in DEK1 occurred during the transition to land plants. Based on genetic complementation of the Arabidopsis thaliana dek1‐3 mutant using CysPc–C2L domains of various origins, we show that these two domains have been functionally conserved within land plants for at least 450 million years. This conclusion is based on the observation that the CysPc–C2L domains of DEK1 from the moss Physcomitrella patens complements the A. thaliana dek1‐3 mutant phenotype. In contrast, neither the CysPc–C2L domains from M. viride nor chimeric animal–plant calpains complement this mutant. Co‐evolution analysis identified differences in the interactions between the CysPc–C2L residues of DEK1 and classical calpains, supporting the view that the two enzymes are regulated by fundamentally different mechanisms. Using the A. thaliana dek1‐3 complementation assay, we show that four conserved amino acid residues of two Ca2+‐binding sites in the CysPc domain of classical calpains are conserved in land plants and functionally essential in A. thaliana DEK1. 相似文献
952.
Zheng Zhang Sriram Jakkaraju Joy Blain Kenneth Gogol Lei Zhao Robert C. Hartley Courtney A. Karlsson Bart L. Staker Thomas E. Edwards Lance J. Stewart Peter J. Myler Michael Clare Darren W. Begley James R. Horn Timothy J. Hagen 《Bioorganic & medicinal chemistry letters》2013,23(24):6860-6863
Published biological data suggest that the methyl erythritol phosphate (MEP) pathway, a non-mevalonate isoprenoid biosynthetic pathway, is essential for certain bacteria and other infectious disease organisms. One highly conserved enzyme in the MEP pathway is 2C-methyl-d-erythritol 2,4-cyclodiphosphate synthase (IspF). Fragment-bound complexes of IspF from Burkholderia pseudomallei were used to design and synthesize a series of molecules linking the cytidine moiety to different zinc pocket fragment binders. Testing by surface plasmon resonance (SPR) found one molecule in the series to possess binding affinity equal to that of cytidine diphosphate, despite lacking any metal-coordinating phosphate groups. Close inspection of the SPR data suggest different binding stoichiometries between IspF and test compounds. Crystallographic analysis shows important variations between the binding mode of one synthesized compound and the pose of the bound fragment from which it was designed. The binding modes of these molecules add to our structural knowledge base for IspF and suggest future refinements in this compound series. 相似文献
953.
Zhinxin Zhao Roberto Gambari Kenneth Ka-Ho Lee Stanton Hon-Lung Kok Raymond Siu-Ming Wong Fung-Yi Lau Johnny Cheuk-On Tang Kim-Hung Lam Chor-Hing Cheng Desmond Kwok Po Hau Chung-Hin Chui Wai-Yeung Wong Wai-Kwok Wong 《Bioorganic & medicinal chemistry letters》2013,23(8):2373-2376
We explore the possible cellular cytotoxic activity of an amphiphilic silicon(IV) phthalocyanine with axially ligated rhodamine B under ambient light experimental environment as well as its in vivo antitumour potential using Hep3B hepatoma cell model. After loading into the Hep3B hepatoma cells, induction of cellular cytotoxicity and cell cycle arrest were detected. Strong growth inhibition of tumour xenograft together with significant tumour necrosis and limited toxicological effects exerted on the nude mice could be identified. 相似文献
954.
Cui-rong Zhao Rui-qi Wang Gang Li Xiao-xia Xue Chang-jun Sun Xian-jun Qu Wen-bao Li 《Bioorganic & medicinal chemistry letters》2013,23(7):1989-1992
New series of indazole based diarylureas were synthesized and their anticancer activity against cancer cells H460, A549, OS-RC-2, HT-29, Lovo, HepG2, Bel-7402, SGC-7901 and MDA-MB-231 were examined. These derivatives of diarylureas, except azaindazole based diarylureas 5f, 5l and 5m, showed superior or similar activity against most of these selected cancer cell lines to the reference compound sorafenib. The effect of substituents on the indazole ring was also investigated. Derivatives with trifluoromenthy or halogen substituent on the indazole ring showed higher activity against the selected cancer cell lines than sorafenib. The acute toxicity assay showed that compounds 5a, 5b and 5i possessed lower toxicity than sorafenib. Compound 5i with 4-(trifluoromenthy)-1H-indazole and 4-(trifluoromenthy) benzene moieties exhibited the most potent anticancer activity. 相似文献
955.
Simeon Bowers Ying-zi Xu Shendong Yuan Gary D. Probst Roy K. Hom Wayman Chan Andrei W. Konradi Hing L. Sham Yong L. Zhu Paul Beroza Hu Pan Eric Brecht Nanhua Yao Julie Lougheed Danny Tam Zhao Ren Lany Ruslim Michael P. Bova Dean R. Artis 《Bioorganic & medicinal chemistry letters》2013,23(7):2181-2186
The structure–activity relationship of a series of dihydroisoquinoline BACE-1 inhibitors is described. Application of structure-based design to screening hit 1 yielded sub-micromolar inhibitors. Replacement of the carboxylic acid of 1 was guided by X-ray crystallography, which allowed the replacement of a key water-mediated hydrogen bond. This work culminated in compounds such as 31, which possess good BACE-1 potency, excellent permeability and a low P-gp efflux ratio. 相似文献
956.
Hai-Chuan Zhao Yan-Ping Shi Yu-Ming Liu Cai-Wen Li Li-Na Xuan Peng Wang Kai Zhang Bao-Quan Chen 《Bioorganic & medicinal chemistry letters》2013,23(24):6577-6579
A series of novel 1,3-selenazole-containing 1,3,4-thiadiazole derivatives bearing Schiff base moieties were synthesized and evaluated for their in vitro antiproliferative activities against human breast cancer cell MCF-7 and mouse lymphocyte leukemia cell L1210 by CCK-8 assay. The majority of the compounds showed better activity against MCF-7 cell, compared with lead compound PCS. In particular, compound 6c was the most potent compound with IC50 value of 4.02 μM. 相似文献
957.
Guo-Wu Rao Cui Wang Jian Wang Zhen-Guo Zhao Wei-Xiao Hu 《Bioorganic & medicinal chemistry letters》2013,23(23):6474-6480
3,6-Diaryl-dihydro-1,2,4,5-tetrazine derivatives were synthesized and their structures were confirmed by single-crystal X-ray diffraction. Monosubstituted dihydrotetrazines are the 1,4-dihydro structure, but disubstituted dihydrotetrazines are the 1,2-dihydro structure. The results of further research indicated there may be a rearrangement during the synthesis process of disubstituted dihydrotetrazines. Their antitumor activities were evaluated against A-549 and P388 cells in vitro. The results showed several compounds to be endowed with cytotoxicity in the low micromolar range. Two compounds were highly effective against A-549 cell and IC50 values were 0.575 and 2.08 μM, respectively. Three-dimensional quantitative structure–activity relationship (3D-QSAR) studies of comparative molecular field analysis (CoMFA) and comparative molecular similarity indices analysis (CoMSIA) were carried out on 37 1,2,4,5-tetrazine derivatives with antitumor activity against A-549 cell. Models with good predictive abilities were generated with the cross validated q2 values for CoMFA and CoMSIA being 0.744 and 0.757, respectively. Conventional r2 values were 0.978 and 0.988, respectively, the predicted R2 values were 0.916 and 0.898, respectively. The results provide the tool for guiding the design and synthesis of novel and more potent tetrazine derivatives. 相似文献
958.
Carl R. Illig Carl L. Manthey Sanath K. Meegalla Mark J. Wall Jinsheng Chen Kenneth J. Wilson Renee L. DesJarlais Shelley K. Ballentine Carsten Schubert Carl S. Crysler Yanmin Chen Christopher J. Molloy Margery A. Chaikin Robert R. Donatelli Edward Yurkow Zhao Zhou Mark R. Player Bruce E. Tomczuk 《Bioorganic & medicinal chemistry letters》2013,23(23):6363-6369
Structure–activity relationship (SAR) studies on a highly potent series of arylamide FMS inhibitors were carried out with the aim of improving FMS kinase selectivity, particularly over KIT. Potent compound 17r (FMS IC50 0.7 nM, FMS cell IC50 6.1 nM) was discovered that had good PK properties and a greater than fivefold improvement in selectivity for FMS over KIT kinase in a cellular assay relative to the previously reported clinical candidate 4. This improved selectivity was manifested in vivo by no observed decrease in circulating reticulocytes, a measure of bone safety, at the highest studied dose. Compound 17r was highly active in a mouse pharmacodynamic model and demonstrated disease-modifying effects in a dose-dependent manner in a strep cell wall-induced arthritis model of rheumatoid arthritis in rats. 相似文献
959.
Zhen-Wei Wu Hai-Wei Xu Gui-Fu Dai Meng-Jiao Liu Li-Ping Zhu Jian Wu Ya-Nan Wang Feng-Juan Wu Dan Zhao Ming-Fu Gao Shan-Shan Nie Wei Han Jing-Hui Song Hong-Min Liu 《Bioorganic & medicinal chemistry letters》2013,23(23):6421-6426
In the present study, andrographolide (Andro, 1) derivatives were screened to identify potent inhibitors against tumor-cell migration and invasion, and associated structure–activity relationships were studied. Compared to 1, compounds 8a–8d exhibited more potent activities against migration in SGC-7901, PC-3, A549, HT-29 and Ec109 cell lines. Improved activities against tumor-cell migration and invasion were proved to be associated with the down-regulation of MMPs. 相似文献
960.
Guohua Zhao Chet Kwon Sharon N. Bisaha Philip D. Stein Karen A. Rossi Xueying Cao Thao Ung Ginger Wu Chen-Pin Hung Sarah E. Malmstrom Ge Zhang Qinling Qu Jinping Gan William J. Keim Mary Jane Cullen Kenneth W. Rohrbach James Devenny Mary Ann Pelleymounter Jeffrey A. Robl 《Bioorganic & medicinal chemistry letters》2013,23(13):3914-3919
The 5-HT2C receptor has been implicated as a critical regulator of appetite. Small molecule activation of the 5-HT2C receptor has been shown to affect food intake and regulate body weight gain in rodent models and more recently in human clinical trials. Therefore, 5-HT2C is a well validated target for anti-obesity therapy. The synthesis and structure–activity relationships of a series of novel tetrahydropyrazinoisoquinolinone 5-HT2C receptor agonists are presented. Several members of this series were identified as potent 5-HT2C receptor agonists with high functional selectivity against the 5-HT2A and 5-HT2B receptors and reduced food intake in an acute rat feeding model upon oral dosing. 相似文献