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1.
Euphorbia species (Family: Euphorbeaceae) have wide applicability in traditional medicines and biofuel sector, and are also rich sources of secondary metabolites, especially terpenoids, attributed with various pharmacological properties. Though 82 Euphorbia species are reported in India, most of the species are uninvestigated for their constituents or potential utilities. Present study reports the isolation and characterization of chemical constituents, estimation of major triterpenoids using a validated HPTLC method and cytotoxicity of plant and latex extracts of Euphorbia trigona. As the secondary metabolites epi-friedelinyl acetate, 3β-friedelinol, taraxerol, rhoiptlenone, stigmasterol and stearic acid were isolated and characterized from E. trigona. HPTLC estimation showed 3β-friedelinol at 0.91 ?± ?0.11% and taraxerol at 1.45 ?± ?0.12% was present in E. trigona plant powder (dry weight). Plant and latex extracts were found non toxic towards normal cell line H9C2 (cardiac myoblasts) and showed insignificant cytotoxic effects towards HeLa (cervical cancer cell line) upto 100 ?μg/ml concentration.  相似文献   
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Neelamegam Ramesh 《Tetrahedron》2008,64(9):2071-2079
A detailed study on the interaction of N-protected bromomethylindoles with various types of aryl/alkyl Grignard is reported. Full experimental details on the mechanism of the unusual dimerization reaction are presented.  相似文献   
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The present study aimed to analyze the in vitro antibacterial, antioxidant, larvicidal and cytotoxicity properties of green synthesized silver nanoparticles (Ag NPs) using aqueous extracts from fruits of Lagerstroemia speciosa and flowers of Couropita guinensis. Synthesized Ag NPs were characterized using UV-DRS, FTIR, XRD, DLS, and High-Resolution SEM and TEM analyses. Absorption wavelength was observed at 386 nm by UV-DRS analysis and energy band gap was calculated as 3.24 eV. FTIR analysis showed the existence of various functional groups in the aqueous extract and in the NPs. DLS analysis showed the stability and particle size of the synthesized Ag NPs. SEM analysis revealed that Ag NPs are in a face centered cubic symmetry and spherical shape with a size of 23.9 nm. TEM analysis showed particle size as 29.90 nm. Ag NPs showed antibacterial activity against both Gram-positive and Gram-negative bacteria. DPPH scavenging trait of Ag NPs was ranging from 20.0 ± 0.2% to 62.4 ± 0.3% and observed significant larvicidal activity (LC50 at 0.742 ppm and LC90 at 6.061 ppm) against Culex quinquefasciatus. In vitro cytotoxicity activity of Ag NPs was also tested against human breast cancer (MCF-7) and fibroblast cells (L-929) and found that cells viabilities are ranging (500 to 25 µg/mL) from 52.5 ± 0.4 to 94.0 ± 0.7% and 53.6 ± 0.5 to 90.1 ± 0.8%, respectively. The synthesized Ag NPs have the potential to be used in the various biomedical applications.  相似文献   
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A variety of N-protected indolylmethylbromides are carbonylated using 5 mol % Pd(PPh3)2Cl2 under Stille conditions in the presence of an alcohol to afford the corresponding methyl/ethyl esters.  相似文献   
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Lewis acid–mediated arylation of N-protected 2/3-bromomethylindoles with different types of arenes is reported.  相似文献   
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This paper discusses the determination of calcium in wine samples using Programmable Systemon-Chip (PSoC) microcontroller. This embedded system uses a PSoC CY8C27443 integrated circuit (IC) spectrophotometer as core unit, high intensity orange LED as light source and photodiode as light detector having the relative spectral sensitivity above 93% in the range of 550–650 nm. This single-chip design reduces hardware complexity and increases the stability by miniaturizing the device. The instrument obeys Beer’s law up to the concentration of 160 mg/L. Coloring agent Methylthymol Blue (MTB) forms a complex with calcium in presence of alkali (pH ≈ 12); the complex exhibits maximum absorbance at 610 nm. The spectral range, concentration of MTB and pH of the solution at which the reaction is carried out are optimized. The results of the developed method are compared statistically with those obtained by a conventional method by applying Student’s t-test and F-test. The regression analysis reveals excellent correlation (R 2 = 0.9998) and regression line equation obtained for that line Y = 0.29 + 0.99X with standard error of 0.62. It can be concluded that the obtained results are in good agreement with the reference method at 95% confidence level.  相似文献   
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