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861.
Pahangensin A and B,two new antibacterial diterpenes from the rhizomes of Alpinia pahangensis Ridley
Yasodha Sivasothy Halijah Ibrahim Audra Shaleena Paliany Siti Aisyah Alias Khalijah Awang 《Bioorganic & medicinal chemistry letters》2013,23(23):6280-6285
The rhizomes of Alpinia pahangensis Ridley yielded a new bis-labdanic diterpene for which the name pahangensin A (1) was proposed along with a new labdane diterpene, pahangensin B (2). Their structures were elucidated by spectroscopic methods including, 1D and 2D NMR techniques and LCMS-IT-TOF analysis. Pahangensin A (1) was found to be an antibacterial agent against Staphylococcus aureus, Bacillus cereus and Bacillus subtilis with MIC values less than 100 μg/mL, respectively. Pahangensin B (2) exhibited antibacterial activity (MIC <100 μg/mL) against B. cereus. 相似文献
862.
Federica Vacondio Caterina Carmi Elena Galvani Michele Bassi Claudia Silva Alessio Lodola Silvia Rivara Andrea Cavazzoni Roberta R. Alfieri Pier Giorgio Petronini Marco Mor 《Bioorganic & medicinal chemistry letters》2013,23(19):5290-5294
In the present study, a small set of reversible or irreversible 4-anilinoquinazoline EGFR inhibitors was tested in A549 cells at early (1 h) and late (8 h) time points after inhibitor removal from culture medium. A combination of assays was employed to explain the observed long-lasting inhibition of EGFR autophosphorylation. We found that EGFR inhibition at 8 h can be due, besides to the covalent interaction of the inhibitor with Cys797, as for PD168393 (2) and its prodrug 4, to the intracellular accumulation of non-covalent inhibitors by means of an active cell uptake, as for 5 and 6. Compounds 5–6 showed similar potency and duration of inhibition of EGFR autophosphorylation as the covalent inhibitor 2, while being devoid of reactive groups forming covalent bonds with protein thiols. 相似文献
863.
Lin Zhou Xuefeng Ge Jihua Liu Jiahong Zhou Shaohua Wei Fuyou Li Jian Shen 《Bioorganic & medicinal chemistry letters》2013,23(19):5317-5324
Hypocrellin A (HA), an a natural perylene quinine photosensitizers (PSs), can chelate with heavy metal ions, including Au(III) and Pt(IV), to form a 1:2 complex, which exhibits enhanced 1O2 generation quantum yield through the increased intersystem crossing efficiency mediated by internal heavy atom effect. Besides, the chelate process greatly improved the water solubility of HA. Comparative studies with HA and complexes have demonstrated that the heavy-atom effect on HA molecules enhances the efficiency of in vitro photodynamic (PDT) efficacy. 相似文献
864.
Youguang Zheng Ming Zheng Xin Ling Yi Liu Yunsheng Xue Lin An Ning Gu Min Jin 《Bioorganic & medicinal chemistry letters》2013,23(12):3523-3530
Novel pyrazole–benzimidazole derivatives have been designed and synthesized. The entire target compounds were determined against cancer cell lines U937, K562, A549, LoVo and HT29 and were screened for Aurora A/B kinase inhibitory activity in vitro. The compounds 7a, 7b, 7i, 7k and 7l demonstrated significant cancer cell lines and Aurora A/B kinase inhibitory activities. Molecular modeling studies suggested the derivatives have bound in the active site of Aurora A kinase through the formation of four hydrogen bonds. Quantum chemical studies were carried out on these compounds to understand the structural features essential for activity. The cellular activity of 7k was also tested by immunofluorescence. 相似文献
865.
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
866.
Kevin Anderson Yi Chen Zhi Chen Romyr Dominique Kelli Glenn Yang He Cheryl Janson Kin-Chun Luk Christine Lukacs Ann Polonskaia Qi Qiao Aruna Railkar Pamela Rossman Hongmao Sun Qing Xiang Masha Vilenchik Peter Wovkulich Xiaolei Zhang 《Bioorganic & medicinal chemistry letters》2013,23(24):6610-6615
DYRK1B is a kinase over-expressed in certain cancer cells (including colon, ovarian, pancreatic, etc.). Recent publications have demonstrated inhibition of DYRK1B could be an attractive target for cancer therapy. From a data-mining effort, the team has discovered analogues of pyrido[2,3-d]pyrimidines as potent enantio-selective inhibitors of DYRK1B. Cells treated with a tool compound from this series showed the same cellular effects as down regulation of DYRK1B with siRNA. Such effects are consistent with the proposed mechanism of action. Progress of the SAR study is presented. 相似文献
867.
Ahmed Aboul-Fotouh Mourad Seikou Nakamura Tsubasa Ueno Takahiro Minami Takanari Yagi Haruka Yasue Ryoko Komatsu Masayuki Yoshikawa Ashraf Mohamed Taye Mohamed Ahmed El-Moselhy Mohamed Montaser Khalifa Hisashi Matsuda 《Bioorganic & medicinal chemistry letters》2013,23(17):4813-4816
In a previous study, retrofractamide A from the fruit of Piper chaba was shown to promote adipogenesis in 3T3-L1 cells. In the present study, retrofractamide A and its derivatives were synthesized, and their adipogenetic effects in 3T3-L1 cells were examined. Among the tested compounds, an amide composed of 9-(3′,4′-methylenedioxyphenyl)-nona-2E,4E,8E-trienoic acid and an n-butyl or n-pentyl amine showed strongest activity. Moreover, the amide with the n-pentyl amine moiety significantly increased the uptake of 2-deoxyglucose into the cells, and also increased the mRNA levels of adiponectin, peroxisome proliferator-activated receptor γ2 (PPARγ2), glucose transporter 4 (GLUT4), fatty acid-binding protein (aP2), and CCAAT/enhancer-binding protein (C/EBP) α and β in a similar manner as the PPARγ agonist troglitazone, although it had less agonistic activity against PPARγ. 相似文献
868.
869.
《Molecular membrane biology》2013,30(3):147-163
Both concanavalin A (con A) and its divalent derivative, succinyl-concanavalin A (S-con A) are mitogenic for porcine lymph node lymphocytes. We have compared the binding of these two lectins to intact porcine lymphocytes and phospholipid vesicles containing reconstituted lymphocyte membrane glycoproteins. Both con A and S-con A showed high- and low-affinity binding to intact cells, as indicated by LIGAND analysis of Scatchard plots of binding data. Despite the apparently identical saccharide specificities of the two lectins, high-affinity binding sites for S-con A were only one-third as numerous as high-affinity sites for the parent lectin. Large numbers of low-affinity binding sites existed for con A, while many fewer were present for S-con A. It is suggested that these sites result from hydrophobic association. Con A bound to lymphocytes in a positively cooperative fashion, while S-con A showed non-cooperative behavior. Lectin binding to large unilamellar phospholipid vesicles containing reconstituted lymphocyte membrane glycoproteins was measured using a rapid filtration assay, and was linear with the glycoprotein content of the vesicles. Almost all of the outward-facing glycoprotein was functional in terms of lectin binding. Reconstituted glycoproteins showed only a single class of high-affinity binding sites for both con A and S-con A, with association constants similar to those measured for intact cells. Con A, but not S-con A, showed positively cooperative binding to reconstituted vesicles. Cooperativity was observed in both gel phase and liquid crystalline phase lipid, and was thus not dependent on long-range lateral rearrangement of glycoprotein receptors. Results suggested that con A induces a microre-distribution of receptors on the lymphocyte membrane surface, leading to the exposure of glycoproteins that were previously inaccessible to the lectin. S-Con A does not cause glycoprotein redistribution, and a large fraction of the receptors remain cryptic. 相似文献
870.
Tiziana Bozzini Giorgia Botta Michela Delfino Silvano Onofri Raffaele Saladino Donatella Amatore Rossella Sgarbanti Lucia Nencioni Anna Teresa Palamara 《Bioorganic & medicinal chemistry》2013,21(24):7699-7708
Catechol derivatives with lipophilic properties have been selectively synthesized by tyrosinase in high yield avoiding long and tedious protection/deprotection steps usually required in traditional procedures. The synthesis was effective also with immobilized tyrosinase able to perform for more runs. The novel catechols were evaluated against influenza A virus, that continue to represent a severe threat worldwide. A significant antiviral activity was observed in derivatives characterized by antioxidant activity and long carbon alkyl side-chains, suggesting the possibility of a new inhibition mechanism based on both redox and lipophilic properties. 相似文献