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The porcine pancreatic elastase inhibition and free-radical scavenging play a crucial role in age progression. All the series of 10 newly synthesized benzimidazole thioureas ( 4a-j ) were assessed for elastase inhibition and radical scavenging activity to identify the suitable anti-aging ingredient for cosmetics products. The compounds 4e , 4f , 4g , and 4h showed inhibition better than the standard, while compound 4f showed the most significant elastase inhibition with the IC50 value of 1.318 ± 0.025 μM compared with oleanic acid IC50 13.451 ± 0.014 used ±1.989 and 41.563 ± 0.824, respectively, as standard. Molecular docking studies were performed and the compound 4f showed binding energy of 7.2 kcal/mol. Kinetics studies revealed inhibition of the pancreatic elastase in a competitive manner. The relative binding energy and structure activity relationship (SAR) identified compound 4f as an effective inhibitor of porcine pancreatic elastase. Compounds 4e and 4i showed remarkable free-radical scavenging activity with SC50 values of 26.421.  相似文献   
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Nanocrystalline cobalt ferrites with nominal composition CoCrxFe2−xO4 ranging from x=0.0 to 0.5 with step increment of 0.25 were prepared by sol–gel auto combustion and chemical co-precipitation techniques. A comparative study of structural, electrical and magnetic properties of these ferrites has been measured using different characterization techniques. Structural and micro-structural studies were measured using X-ray diffraction, Fourier transform infra-red spectroscopy (FTIR), scanning electron microscopy and atomic force microscopy. Crystallite sizes of the series are within the range of 12–29±2 nm. Lattice parameters decrease by increasing Cr3+ concentration. FTIR confirms the presence of two lattice absorption bands. DC electrical resistivity increases to a value of ∼1010 Ω-cm with increase in Cr3+ concentration, but the most significant increase is in samples prepared by sol–gel combustion. Dielectric properties have been measured as a function of frequency at room temperature. Dielectric loss decreases to 0.1037 and 0.0108 at 5 MHz for chemical co-precipitation and sol–gel combustion, respectively. Impedance measurements further helped in analyzing the electrical properties and to separate the grain and grain boundary resistance effects using a complex impedance analysis. Magnetic parameters were studied using a vibrating sample magnetometer in the applied field of 10 kOe. The saturation magnetization decreased from 63 to 10.8 emu/gm with increase in Cr3+ concentration.  相似文献   
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Research on Chemical Intermediates - Meldrum’s acid derivatives were facile synthesized by one-pot condensation process and characterized by NMR (1H, 13C, DEPT-90 and DEPT-135) and EI-MS. The...  相似文献   
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Compound 3 {(E)-1-(2-fluorobenzylidene)thiosemicarbazide} – a new Schiff base of thiosemicarbazide has been synthesized, characterized and reported for crystal structure. Planer side chain in the crystal structure was observed co-planer with aromatic ring plane and molecules were connected into centrosymmetric dimmers via intermolecular hydrogen bonding. DFT geometry optimization and the relevant quantum parameters indicated unstable and reactive nature of compound 3. Experimental and theoretical findings for DNA binding by UV–visible, cyclic voltammetry and molecular docking studies showed consistency in kinetic (Kb) and thermodynamic (ΔG) parameters and that compound 3 significantly interacted with DNA via intercalation. Viscometric analysis further comprehended intercalation as possible binding mode of the compound with DNA and non-denaturing of DNA in the presence of 10% aqueous DMSO. Docked parameters further assured the drug like characteristics of the investigated compound as fit in Lipinski’s criteria. Dose dependant cytotoxic activity of compound 3 against human Huh-7 cell line indicated its anti-cancer potential at 100?µg/ml concentration.  相似文献   
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The kinetics of the reaction between vitamin C (l-ascorbic acid) and ferric chloride hexahydrate was investigated in acidic medium at pH 3 spectrophotometrically. The order of the reaction was established by applying different methods, such as initial rate method, integration method and half-life method. The results obtained from each method were correlated with each other and consistency in all methods was observed. The order of the reaction with respect to each reactant was found first and the overall second order was recommended for the reaction.  相似文献   
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Merocyanine 540 (MC540) was activated by exposure to 514 nm laser light. The light-exposed MC540 was then mixed (in the dark) with tumor cells and normal cells to determine the antiproliferative activity. Treatment with light-exposed MC540 resulted in 70-90% tumor cell kill from different cell lines, while 85% of the normal human mononuclear cells and 41% of the granulocyte-macrophage colony forming cells (CFU-GM) survived the treatment. The observed cytotoxicity of light-exposed MC540 to the tumor cells was significantly greater (P less than 0.05) than the native MC540. Results show that tumor cell specificity and cytotoxicity in the light activated dye are retained for at least 30 days. Addition of catalase and mannitol decreased the cell kill by light-exposed compound, indicating that the observed effects may be due to reactive oxygen species. The electron micrographs of treated cells show a progression towards apoptosis in a majority of the cells. The life span of L1210 leukemia-bearing mice treated with light-exposed MC540 was prolonged compared to the untreated and native MC540 treated mice. High pressure liquid chromatography (HPLC) analysis of light-exposed material shows a completely different elution profile compared to the native compound. Results presented here show that light-exposed photoactive compounds can be used without further illumination and may have significant clinical applications. Photoactive mechanisms dependent on events other than short-lived transient elevations in energy or singlet oxygen must be invoked to explain the reported cytotoxicity.  相似文献   
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This article describes the design and synthesis of a series of novel amantadine-thiourea conjugates (3a–j) as Jack bean urease inhibitors. The synthesized hybrids were assayed for their in vitro urease inhibition. Accordingly, N-(adamantan-1-ylcarbamothioyl)octanamide (3j) possessing a 7-carbon alkyl chain showed excellent activity with IC50 value 0.0085 ± 0.0011 µM indicating that the long alkyl chain plays a vital role in enzyme inhibition. Whilst N-(adamantan-1-ylcarbamothioyl)-2-chlorobenzamide (3g) possessing a 2-chlorophenyl substitution was the next most efficient compound belonging to the aryl series with IC50 value of 0.0087 ± 0.001 µM. The kinetic mechanism analyzed by Lineweaver–Burk plots revealed the non-competitive mode of inhibition for compound 3j. Moreover, in silico molecular docking against target protein (PDBID 4H9M) indicated that most of the synthesized compounds exhibit good binding affinity with protein. The compound 3j forms two hydrogen bonds with amino acid residue VAL391 having a binding distance of 1.858 Å and 2.240 Å. The interaction of 3j with amino acid residue located outside the catalytic site showed its non-competitive mode of inhibition. Based upon these results, it is anticipated that compound 3j may serve as a lead structure for the design of more potent urease inhibitors.  相似文献   
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