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11.
H. Raissi A. F. Jalbout M. Yoosefian Mustapha Fazli A. Nowroozi M. Shahinin A. De Leon 《International journal of quantum chemistry》2010,110(4):821-830
The molecular structure and intramolecular hydrogen bond energies of 44 conformers of 2‐Amino methylene malonaldehyde were investigated at MP2 and B3LYP levels of theory using the standard 6‐311++G** basis set and AIM and NBO analysis. The calculated geometrical parameters and conformational analysis in gas phase show that the closed ring via intramolecular hydrogen bonded conformers of this compound are more stable than the other ones. Hydrogen bond energies for H‐bonded conformers were obtained from the related rotamers method (RRM) and Schuster method, and also the nature of H‐bonding of them has been investigated by means of the Bader theory of atoms in molecules, which is based on topological properties of the electron density. Delocalization effects can be identified from the presence of off diagonal elements of the Fock matrix in the NBO basis. © 2009 Wiley Periodicals, Inc. Int J Quantum Chem, 2010 相似文献
12.
The essential oils (EOs) obtained by solvent-free microwave extraction (SFME) and hydrodistillation (HD) from endemic Origanum husnucanbaseri H. Duman, Aytac & A. Duran were investigated using the gas chromatography-mass spectrometry system. The main constituents of both oils obtained from SFME and HD from O. husnucanbaseri are borneol (15.2-12.8%), α-terpineol (12.3-10.8%) and trans-sabinene hydrate (11.8-9.92%). The EO obtained from SFME contained substantially higher amounts of oxygenated compounds and lower amounts of monoterpenes than that from HD. The antibacterial activities of the EOs from SFME and HD were evaluated by the disc diffusion method against six bacterial strains. The EO extracted by SFME was more effective than the EO extracted by HD against the tested bacteria, except for Klebsiella pneumoniae American type culture collection (ATCC) 13883. Streptococcus pyogenes ATCC 19615 and Staphylococcus aureus ATCC 25923 in particular were more sensitive against the EO extracted by SFME. 相似文献
13.
O. Altan Bozdemir Dr. Yusuf Cakmak Fazli Sozmen Tugba Ozdemir Aleksander Siemiarczuk Dr. Engin U. Akkaya Prof. Dr. 《Chemistry (Weinheim an der Bergstrasse, Germany)》2010,16(21):6346-6351
Multichromophoric boron‐dipyrromethene (Bodipy) dyes synthesized on phenylene‐ethynylene platforms have been be converted to energy transfer cassettes in a one‐step chemical transformation. Excitation energy transfer processes in these highly symmetrical derivatives were studied in detail, including time‐resolved fluorescence spectroscopy techniques. Excitation spectra and the emission lifetimes suggest efficient energy transfer between the donor and acceptor chromophore. These novel energy transfer cassettes, while highlighting a short‐cut approach to similar energy transfer systems, could be useful as large pseudo‐Stokes shift multichromophoric dyes with potential applications in diverse applications. 相似文献
14.
Vukadin M. Leovac Vladimir Divjaković Refik Fazlić Peter Engel 《Transition Metal Chemistry》1989,14(2):139-142
Summary The reaction of a warm ethanolic solution of CoII perchlorate or rodanide and NiII acetate with 2-furaldehydeS-methylisothiosemicarbazone (HL), yielded the complexes [Co(HL)2(H2O)](ClO4)2 (1), [Co(HL)3] [Co(NCS)4] (2) and NiL2, respectively. Both CoII complexes are high-spin, whereas the NiII complex is in lowspin state (diamagnetic). An x-ray analysis of (1) showed it to have atrans-trigonal bipyramidal configuration in which one coordination site in the equatorial plane is occupied by one H2O molecule. HL, a bidentate ligand, is coordinatedvia N(1) and N(4). The tris(ligand) cation in complex (2) has an octahedral configuration. Complex NiL2 has a square-planar configuration.The deep purple plate-like crystals of (1) are monoclinic with space group C2/c, having cell parameters:a=11.369(3),b=13.029(4),c=17.438(5) Å; =103.39(2)o. The structure was solved by the heavy-atom method and refined by least-squares method to an R value of 0.060 for 1761 observed reflections. 相似文献
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Fazli Khuda Zafar Iqbal Yasar Shah Muhammad Abbas Zakiullah Muhammad Hassan 《Chromatographia》2016,79(9-10):609-618
16.
Zurina Shaameri Sharifah Hidayah Sharif Ali Mohd Fazli Mohamat Bohari M. Yamin Ahmad Sazali Hamzah 《Journal of heterocyclic chemistry》2013,50(2):320-325
A brief and efficient approach for the synthesis of (±)‐5‐benzyl‐4‐hydroxy‐2‐pyrrolidine ( 1 ) from phenylalanine racemate is described. The key step is the stereocontrolled reduction of the keto functionality of benzylated pyrrolidinone intermediate ( 6 ) via sodium borohydride in carboxylic acid medium furnishing both (R,R)‐ and (S,S)‐configured diastereomers. The natural (R,R) enantiomer ( 2 ), however, crystallized out from its racemic mixture. Structure of 2 was confirmed by NMR, IR, elemental analyzer, and single crystal X‐ray crystallographic techniques. 相似文献
17.
An efficient, general procedure for reductive methylation of primary and secondary amines with 37% formaldehyde using N-methylpyrrolidine zinc borohydride (ZBHNMP) as a reducing agent gave the corresponding tertiary amines in excellent yields. The reaction was carried out in tetrahydrofuran under neutral conditions at 0–10 °C. 相似文献
18.
Ihsan Ilahi Fazli Khuda Muhammad Umar Khayam Sahibzada Saad Alghamdi Rahim Ullah Anas S. Dablool Mehboob Alam Ayub Khan Atif Ali Khan Khalil 《Arabian Journal of Chemistry》2021,14(5):103110
Treatment of microbial infections and inflammatory conditions have many challenges in terms of efficacy and safety issues. Novel approaches such as nanoparticles based drug delivery system have shown promising results to solve some of these problems. The aim of this study was to exploit the efficacy of the synthesized silver nanoparticles. In this study, silver nanoparticles (AgNPs) were biosynthesized using root extract (aqueous) of Duchesnea indica. They were characterized using different techniques such as, ultraviolet–visible (UV–Vis) spectrophotometry, transmission and scanning electron microscopy (TEM and SEM), X-ray diffractometer (XRD), energy dispersive X-ray spectroscopy (EDX), fourier-transform infrared spectroscopy (FTIR) and zetasizer. The UV–Vis spectra gave a characteristic peak at 423 nm; XRD confirmed its crystalline structure; FTIR confirmed the involvement of phytochemicals in their capping and reduction; TEM images confirmed their spherical shape with average width of 20.49 nm and average area of 319.25 nm2. Various biological activities were performed on these NPs, such as antimicrobial, anti-inflammatory, analgesic and muscle relaxant, which showed significant results as follow. Among bacterial strains, Salmonella typhi (MIC: 0.01 mg/ml) and Escherichia coli (MIC: 0.01 mg/ml), while among that of fungal Microsporum canis (MIC: 0.53 mg/ml) and Alternaria alternata (MIC: 0.51 mg/ml) were most susceptible. The AgNPs showed maximum anti-inflammatory activity (46.15 and 56.85%) at 20 mg/kg after 3 and 5 h of drug administration, comparable to that of standard. In-vivo model exhibited concentration dependent inhibition of both COX-2 and 5-LOX enzymes. Similarly, it exhibited maximum analgesic activity (54.24%) at 20 mg/kg dose after 60 min. of pain induction. Furthermore, they depicted maximum muscle relaxation (P < 0.01) after 60 and 90 min of drug administration. Above results suggest that these AgNPs can be studied further for the development of more effective and safe formulations. 相似文献
19.
Abdullahi Shittu Ismail Aznan Fazli Yasir Muhamad Samudi 《Journal of Radioanalytical and Nuclear Chemistry》2020,324(1):301-315
In this study, 52 samples of ceramic materials were studied for 226Ra, 222Rn, 232Th and 40K natural radionuclides using high-purity germanium detector and relevant radiological hazards parameters were also appraised. Furthermore, the long-term variations of the total effective dose equivalent (TEDE) and effects of wall thickness on TEDE were established and analyzed using RESRAD-BUILD computer code. The observed percentage variations of TEDE are 2% and 8% for 226Ra and 232Th, respectively, while no variation observed for external dose due to 40K. The estimated indoor doses from the studied ceramic materials are all below the recommended maximum limit.
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