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101.
Chunlei Tang Guolong Gu Bin Wang Xin Deng Xiaoyun Zhu Hai Qian Wenlong Huang 《Chemical biology & drug design》2014,83(3):324-333
Poor water solubility limits the clinical use of andrographolide and its derivatives. In an attempt to develop potent hepatoprotective drugs, a strategy was proposed to improve the aqueous solubility of andrographolide. Ten andrographolide derivatives were designed, synthesized, evaluated for aqueous solubility and in vivo hepatoprotective activity against CCl4‐induced liver injury in mice. As expected, the aqueous solubility of synthetic derivatives was effectively improved. All compounds demonstrated the effect of different degrees in improving the liver enzyme (ALT and AST) activity, especially the most promising compound 9d significantly improved liver enzyme activity, with high potency to be a new lead. 相似文献
102.
Felipe J. Cavichioli Graylin N.B. Bernal Iandra Holzmann Juliana Bagatini Klein Ricardo Escarcena Esther Del Olmo Arturo San Feliciano Valdir Cechinel Filho Nara L.M. Quintão 《Pharmacological reports : PR》2018,70(4):753-759
Background
The study evaluated the effects of two sphingosine derivatives N-(2-tert-butoxycarbamylhexadecyl)glutaramide (AA) and N-(1-benzyloxyhexadec-2-yl)glutaramide (OA) in different models of hypersensitivity in mice.Methods
Male Swiss mice were orally pre-treated with AA or OA (0.3–3 mg/kg). After 1 h, they received λ-carrageenan (300 μg/paw), lipopolysaccharide (LPS; 100 ng/paw), bradykinin (BK; 500 ng/paw) or prostaglandin E2 (PGE2; 0.1 nmol/paw) or epinephrine (100 ng/paw), and the mechanical withdrawal thresholds were evaluated using von Frey filament (0.6 g) at different time points. The effect of the compounds against inflammatory and neuropathic pain was also evaluated using complete Freund’s adjuvant (CFA), or by performing partial sciatic nerve ligation (PSNL).Results
Animals pre-treated with AA and OA reduced hypersensitivity induced by carrageenan, LPS and BK, and modest inhibition of PGE2-induced hypersensitivity and carrageenan-induced paw oedema were observed in mice treated with OA. Though the partial effect presented by AA and OA, when dosed once a day, both compounds were able to significantly reduce the persistent inflammatory and neuropathic pain induced by CFA and PSNL, respectively.Conclusion
These results demonstrate that the sphingosine derivatives AA and OA present important anti-hypersensitive effects, suggesting a possible interaction with the kinin signalling pathway. This may represent an interesting tool for the management of acute and chronic pain, with good bioavailability and safety. 相似文献103.
Synthesis and biological evaluation of phloroglucinol derivatives possessing α‐glycosidase,acetylcholinesterase, butyrylcholinesterase,carbonic anhydrase inhibitory activity 下载免费PDF全文
Serdar Burmaoglu Ali O. Yilmaz Parham Taslimi Oztekin Algul Deryanur Kilic Ilhami Gulcin 《Archiv der Pharmazie》2018,351(2)
104.
Design,synthesis, biological evaluations,molecular docking,and in vivo studies of novel phthalimide analogs 下载免费PDF全文
Magdy A. H. Zahran Bishoy El‐Aarag Ahmed B. M. Mehany Amany Belal Ali S. Younes 《Archiv der Pharmazie》2018,351(5)
105.
Petra Olejníková L’ubomír ?vorc Denisa Ol?ovská Anna Panáková Zuzana Vihonská Katarína Kovaryová ?tefan Marchalín 《Scientia pharmaceutica》2014,82(2):221-232
The antimicrobial activity of 3-methyl-5-isopropyl (or ethyl) 6-methyl-4-nitrophenyl-1,4-dihydropyridine-3,5-dicarboxylate derivatives was evaluated. Prokaryotes (bacteria) appeared to be more sensitive to their antimicrobial activity than were eukaryotes (filamentous fungi). The best antibacterial activity was shown by derivative 33, which was able to inhibit the growth of Mycobacterium smegmatis (MIC33 = 9 μg.ml−1), Staphylococcus aureus (MIC33 = 25 μg.ml−1), and Escherichia coli (MIC33 = 100 μg.ml−1). In addition, derivative 4 demonstrated its antibacterial power on the acid-fast bacterial species M. smegmatis and on Gram-positive S. aureus. Focusing on the structure-activity relationship, it appears that the increase in the substituent bulk at the C2 position improved the antibacterial activity of the set of compounds studied. Derivatives 33 and 4, carrying 2-cyano-3-oxo-3-phenylprop-1-en-1-yl and allyliminomethyl groups, respectively, showed significantly higher inhibition activities on all tested microorganisms in comparison with the rest of the derivatives. This enhancement was also in good correlation with different log P values (lipophilicity parameter). 相似文献
106.
《Chemical biology & drug design》2018,91(1):277-284
N‐substituted hydroxynaphthalene imino‐oxindole derivatives ( 5a–g ) were emerged as the inhibitors of the phosphoinositide 3‐kinase (PI3K), which is a crucial regulator of apoptosis or programmed cell death. Electron donor‐/acceptor‐substituted indole‐imine ( 5a–g ) was achieved, and the structures were elucidated by FTIR, 1H NMR, 13C NMR and HRMS. Inhibition potency of PI3Ks was assessed by competitive ELISA. Subsequently, an anticancer activity against breast cancer (MCF‐7) cell lines was evaluated. In both activities, compounds 5c , 5d and 5f showed most potent activities. Percentage inhibition for anticancer activity was 78.22 ± 1.02 ( 5c ) and 78.98 ± 1.08 ( 5f ), and the IC50 was 2.02 ± 0.92 μm ( 5c ) and 1.98 ± 0.18 μm ( 5f ). Compounds 5a and 5g were found inactive for both activities, and rest all showed a moderate activity. To get more insight into the binding mode and inhibitor binding affinity, 5a–g were docked into the active site of PI3Ks p110α (PDB ID: 2ENQ). Results suggested that the hydrophobic interactions in the binding pockets of PI3Ks conquered affinity of the most favourable binding ligands ( 5c and 5f : inhibitory constant (ki) = 102.4 and 128.23 nm ). The SAR studies demonstrate the efficiency of 5a–g as the PI3Ks precise inhibitors with the impending to treat various cancers. 相似文献
107.
Antiepileptic drugs (AEDs) are widely utilized in the management of neuropathic pain. The AED valproic acid (VPA) holds out particular promise as it engages a variety of different anticonvulsant mechanisms simultaneously. However, the clinical use of VPA is limited by two rare but potentially life-threatening side effects: teratogenicity and hepatotoxicity. We have synthesized several tetramethylcyclopropyl analogues of VPA amides that are non-teratogenic, and are likely to be non-hepatotoxic, and that exhibit good antiepileptic efficacy. In the present study we have assessed the antiallodynic activity of these compounds in comparison to VPA and gabapentin (GBP) using the rat spinal nerve ligation (SNL) model of neuropathic pain. TMCA (2,2,3,3-tetramethylcyclopropanecarboxylic acid, 100–250 mg/kg), TMCD (2,2,3,3-tetramethylcyclopropanecarboxamide, 40–150 mg/kg), MTMCD (N-methyl-TMCD, 20–100 mg/kg), and TMCU (2,2,3,3-tetramethylcyclopropanecarbonylurea, 40–240 mg/kg) all showed dose-related reversal of tactile allodynia, with ED50 values of 181, 85, 41, and 171 mg/kg i.p., respectively. All were more potent than VPA (ED50 = 269 mg/kg). An antiallodynic effect was obtained for TMCD, MTMCD and TMCU at plasma concentrations as low as 23, 6 and 22 mg/L, respectively. MTMCD was found to be non-toxic, non-sedative and equipotent to gabapentin, currently the leading AED in neuropathic pain treatment. Tetramethylcyclopropyl analogues of VPA amides have potential to become a new series of drugs for neuropathic pain treatment. 相似文献
108.
《Drug discovery today》2021,26(8):1825-1840
Numerous properties of chitosan have led to its extensive use in the formulation of nanomaterials for drug delivery. However, the cationic surface of chitosan-based nanoparticles adsorbs proteins upon exposure to biological fluids, forming a phenomenon known as ‘protein corona’. This causes several effects such as decreased bioavailability and limited in vivo clinical applications of chitosan nanoparticles. Understanding and overcoming the effects of protein adsorption on chitosan nanoparticles is key for drug delivery purposes. This review focuses on the strategies implemented to increase the stability of chitosan nanoparticles in the systemic circulation by averting the formation of protein corona and the limitations of PEGylation. 相似文献
109.
110.