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991.
The phycobilisome (PBS) is a photosynthetic light-harvesting complex in red algae, whose structural genes are separately encoded by both the nuclear and chloroplast genomes. While the expression of PBS genes in both genomes is responsive to environmental changes to modulate light-harvesting efficiency, little is known about how gene expression of the two genomes is coordinated. In this study, we focused on the four nuclear-encoded chloroplast sigma factors to understand aspects of this coordination, and found that SIG2 directs the expression of chloroplast PBS genes in the red alga Cyanidioschyzon merolae. 相似文献
992.
Neuropeptide Y (NPY) and nuclear factor-kappa B (NF-κB) are involved in regulating anorexia elicited by phenylpropanolamine (PPA), a sympathomimetic drug. This study explored whether NPY Y1 receptor (Y1R) is involved in this process, and a potential role for the proopiomelanocortin system was identified. Rats were given PPA once a day for 4 days. Changes in the hypothalamic expression of the NPY, Y1R, NF-κB, and melanocortin receptor 4 (MC4R) levels were assessed and compared. The results indicated that food intake and NPY expression decreased, with the largest reductions observed on Day 2 (approximately 50% and 45%, respectively), whereas NF-κB, MC4R, and Y1R increased, achieving maximums on Day 2 (160%, 200%, and 280%, respectively). To determine the role of Y1R, rats were pretreated with Y1R antisense or a Y1R antagonist via intracerebroventricular injection 1 h before the daily PPA dose. Y1R knockdown and inhibition reduced PPA anorexia and partially restored the normal expression of NPY, MC4R, and NF-κB. The data suggest that hypothalamic Y1R participates in the appetite-suppression from PPA by regulating MC4R and NF-κB. The results of this study increase our understanding of the molecular mechanisms in PPA-induced anorexia. 相似文献
993.
Rainer Gewald Christian Grunwald Ute Egerland 《Bioorganic & medicinal chemistry letters》2013,23(15):4308-4314
Expanding on HTS hit 4 afforded a series of [1,3,5]triazine derivatives as novel PDE4 inhibitors. The SAR development and optimization process with the emphasis on ligand efficiency and physicochemical properties led to the discovery of compound 44 as a potent, selective and orally active PDE4 inhibitor. 相似文献
994.
995.
Mohamed A.O. Abdelfattah Jochen Lehmann Ashraf H. Abadi 《Bioorganic & medicinal chemistry letters》2013,23(18):5077-5081
A series of thienylmethylphenylpiperazins was synthesized and tested for affinity towards the five subtypes of dopaminergic receptors. Compound 5f showed more than 1000 folds selectivity to D4 receptors; analogue 5e showed the highest affinity to D4 receptors with Ki 3.9 nM. An interactive SAR approach was adopted and lead to compound 14a with Ki (D4) as low as 0.03 nM. Molecular docking studies showed a potential, first to report arene cation interaction between the D4 unique residue Arg-186 and the ligands’ arene moiety, explaining the importance of having a strong negative electrostatic potential at this area of the compound structure. 相似文献
996.
Jin Bae Weon Hyun-Jeong Ko Choong Je Ma 《Bioorganic & medicinal chemistry letters》2013,23(24):6732-6736
We isolated 2,3-dihydroxy-4-methoxyacetophenone, a neuroprotective compound from Cynenchum paniculatum in our previous study.The present study was conducted to investigate the possible neuroprotective effect of 2,3-dihydroxy-4-methoxyacetophenone that has been previously isolated from Cynenchum paniculatum on hippocampal neuronal cell line, HT22 cells and its possible cognitive-enhancing effect on scopolamine-induced amnesia in mice.Neuroprotective effect against glutamate-induced neurotoxicity in HT22 cells was evaluated by MTT assay. Also, cognitive enhancing effect against scopolamine (1 mg/kg, ip) induced learning and memory deficit was measured by Morris water maze test. Oral administered of 2,3-dihydroxy-4-methoxyacetophenone (1, 10, 20, 40 and 50 mg/kg) to amnesic mice induced by scopolamine. In Morris water maze test, 2,3-dihydroxy-4-methoxyacetophenone (50 mg/kg) improved the impairment of spatial memory induced by scopolamine. 2,3-Dihydroxy-4-methoxyacetophenone protect HT22 cells on glutamate induced cell-death in a dose-dependent manner (EC50 value: 10.94 μM). Furthermore, 2,3-dihydroxy-4-methoxyacetophenone was found to inhibit [Ca2+] accumulation in HT22 cells and had antioxidantive activity. The results showed that 2,3-dihydroxy-4-methoxyacetophenone exert neuroprotective and cognitive-enhancing activities through its antioxidant activity. We suggest that 2,3-dihydroxy-4-methoxyacetophenone improves cognitive function and may be helpful for the treatment of Alzheimer’s disease. 相似文献
997.
Akihiko Kojima Satoshi Takita Tatsunobu Sumiya Koji Ochiai Kazuhiko Iwase Tetsuya Kishi Akira Ohinata Yuichi Yageta Tokutaro Yasue Yasushi Kohno 《Bioorganic & medicinal chemistry letters》2013,23(19):5311-5316
We previously identified KCA-1490 [(?)-6-(7-methoxy-2-trifluoromethyl-pyrazolo[1,5-a]pyridin-4-yl)-5-methyl-4,5-dihydro-3-(2H)-pyridazinone], a dual PDE3/4 inhibitor. In the present study, we found highly potent selective PDE4 inhibitors derived from the structure of KCA-1490. Among them, N-(3,5-dichloropyridin-4-yl)-7-methoxy-2-(trifluoromethyl)pyrazolo[1,5-a]pyridine-4-carboxamide (2a) had good anti-inflammatory effects in an animal model. 相似文献
998.
Jenifer L. Smith Kassandra I. Rossiter Christopher M. Semko Ying-Zi Xu David A. Quincy Jacek Jagodzinski Michael S. Dappen Andrei W. Konradi Christopher Vandevert Caroline Garrido Wenxian Mao F. Bong San Pablo Brian Wipke Lilibeth Dofiles Angie Wadsworth Eric Peterson Carlos Lorenzana Stellanie Simmonds Ted A. Yednock 《Bioorganic & medicinal chemistry letters》2013,23(14):4117-4119
Mitsunobu reactions were employed to link t-butyl esters of α4 integrin inhibitors at each of the termini of a three-arm, 40 kDa, branched PEG. Cleavage of the t-butyl esters using HCO2H provided easily isolated PEG derivatives, which are potent α4 integrin inhibitors, and which achieve sustained levels and bioactivity in vivo, following subcutaneous administration to rats. 相似文献
999.
François Bilodeau Murray D. Bailey Punit K. Bhardwaj Josée Bordeleau Pat Forgione Michel Garneau Elise Ghiro Vida Gorys Ted Halmos Eric S. Jolicoeur Mélissa Leblanc Christopher T. Lemke Julie Naud Jeff O’Meara Peter W. White Montse Llinàs-Brunet 《Bioorganic & medicinal chemistry letters》2013,23(14):4267-4271
In this report we describe the synthesis and evaluation of diverse 4-arylproline analogs as HCV NS3 protease inhibitors. Introduction of this novel P2 moiety opened up new SAR and, in combination with a synthetic approach providing a versatile handle, allowed for efficient exploitation of this novel series of NS3 protease inhibitors. Multiple structural modifications of the aryl group at the 4-proline, guided by structural analysis, led to the identification of analogs which were very potent in both enzymatic and cell based assays. The impact of this systematic SAR on different drug properties is reported. 相似文献
1000.
Anne Décor Chantal Grand-Maître Oliver Hucke Jeff O’Meara Cyrille Kuhn Léa Constantineau -Forget Christian Brochu Eric Malenfant Mégan Bertrand-Laperle Josée Bordeleau Elise Ghiro Marc Pesant Gulrez Fazal Vida Gorys Michael Little Colette Boucher Sylvain Bordeleau Pascal Turcotte Annick Gauthier 《Bioorganic & medicinal chemistry letters》2013,23(13):3841-3847
We describe here the design, synthesis and biological evaluation of antiviral compounds acting against human rhinovirus (HRV). A series of aminothiazoles demonstrated pan-activity against the HRV genotypes screened and productive structure–activity relationships. A comprehensive investigational library was designed and performed allowing the identification of potent compounds with lower molecular weight and improved ADME profile. 31d-1, 31d-2, 31f showed good exposures in CD-1 mice. The mechanism of action was discovered to be a host target: the lipid kinase phosphatidylinositol 4-kinase III beta (PI4KIIIß). The identification of the pan-HRV active compound 31f combined with a structurally distinct literature compound T-00127-HEV1 allowed the assessment of target related tolerability of inhibiting this kinase for a short period of time in order to prevent HRV replication. 相似文献