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21.
Jabbar Khalafy Nasser EtivandShadi Dilmaghani Mahnaz EzzatiAhmad Poursattar Marjani 《Tetrahedron letters》2014
A simple and convenient synthesis of 2-aryl-3-hydroxy-6,7-dihydro-1H-indol-4(5H)-ones is achieved in high yields via the one-pot, three-component reaction of arylglyoxals, 1,3-cyclohexanedione, and ammonium acetate in water under reflux conditions. 相似文献
22.
23.
Mumtaz Khan T. Jabbar M. Asif M. I. Anjum M. Dilband K. Khan A. Jabbar W. Arshed 《Journal of Radioanalytical and Nuclear Chemistry》2014,299(1):577-582
Technetium (99mTc), a decay product of molybdenum (99Mo), is employed as radioisotope in nuclear medicine. Several practical devices known as generators are commercially available which enable the user to separate the daughter from the parent radionuclide. The present study is focused on quality control of chromatographic technetium generator. A properly constructed generator should comply with international requirements of radionuclide purity of 90Sr/99Mo ≤ 6 × 10?8 and 89Sr/99Mo ≤ 6 × 10?7. For this purpose an analytical method was optimized to quantify radiostrontium (89Sr and 90Sr) in sodium molybdate [Na 2 99 MoO4] solution, a fission product used for 99Mo/99mTc generators. Dowex 1 × 8 and alumina were used in sequence followed by tributyl phosphate extraction for radiostrontium separation. Cerenkov measurement of 89Sr and 90Sr (through its descendent 90Y) was performed using Perkin Elmer Tricarb LSA 3170 with detection efficiency of 42 and 14 %, respectively. Since efficiency of Cerenkov counting is sensitive to presence of color, spectral index of sample was used to correct the counting efficiency. The chemical recovery for strontium was 22 % and for yttrium was 80 % as determined by inductively coupled plasma optical emission spectrometry. Lower limit of detection was found to be 6.3 and 14.4 Bq L?1 for 90Sr and 89Sr, respectively with 60 min counting time. Hence method can be applied successfully to analyze 89,90Sr in fission molybdenum used as radiopharmaceutical with a relative error of <10 %. 相似文献
24.
Sadeghi Mohamad Sadegh Anadalibkhah Naghmeh Ghasemiasl Ramin Armaghani Taher Dogonchi Abdul Sattar Chamkha Ali J. Ali Hafiz Asadi Amin 《Journal of Thermal Analysis and Calorimetry》2022,147(1):1-22
Journal of Thermal Analysis and Calorimetry - The ultimate goal of the present review paper is to summarize and discuss the findings of the most recently published literature on natural convection... 相似文献
25.
Muddaser Shah Waheed Murad Najeeb Ur Rehman Sobia Ahsan Halim Manzoor Ahmed Hazir Rehman Muhammed Zahoor Sidra Mubin Ajmal Khan Mohamed A. Nassan Gaber El-Saber Batiha Ahmed Al-Harrasi 《Molecules (Basel, Switzerland)》2021,26(12)
In the current study, in vitro antimicrobial and antioxidant activities and in vivo anti-inflammatory and analgesic activities of Scutellaria edelbergii Rech. f. (crude extract and subfractions, i.e., n-hexane, ethyl acetate (EtOAc), chloroform, n-butanol (n-BuOH) and aqueous) were explored. Initially, extraction and fractionation of the selected medicinal plant were carried out, followed by phytochemical qualitative tests, which were mostly positive for all the extracts. EtOAc fraction possessed a significant amount of phenolic (79.2 ± 0.30 mg GAE/g) and flavonoid (84.0 ± 0.39 mg QE/g) content. The EtOAc fraction of S. edelbergii exhibited appreciable antibacterial activity against Gram-negative (Escherichia coli and Klebsiella pneumoniae) strains and significant zones of inhibition were observed against Gram-positive bacterial strains (Bacillus subtilis and Staphylococcus aureus). However, it was found inactive against Candida Albicans and Fusarium oxysporum fungal strains. The chloroform fraction was the most effective with an IC50 value of 172 and 74 µg/mL against DPPH (1,1-Diphenyl-2-picryl-hydrazyl) and ABTS assays, in comparison with standard ascorbic acid 59 and 63 µg/mL, respectively. Moreover, the EtOAc fraction displayed significant in vivo anti-inflammatory activity (54%) using carrageenan-induced assay and significant (55%) in vivo analgesic activity using acetic acid-induced writing assay. In addition, nine known compounds, ursolic acid (UA), ovaul (OV), oleanolic acid (OA), β-sitosterol (BS), micromeric acid (MA), taraxasterol acetate (TA), 5,3′,4′-trihydroxy-7-methoxy flavone (FL-1), 5,7,4′-trihydroxy-6,3′-dimiethoxyflavone (FL-2) and 7-methoxy catechin (FL-3), were isolated from methanolic extract of S. edelbergii. These constituents have never been obtained from this source. The structures of all the isolated constituents were elucidated by spectroscopic means. In conclusion, the EtOAc fraction and all other fractions of S. edelbergii, in general, displayed a significant role as antibacterial, free radical scavenger, anti-inflammatory and analgesic agents which may be due to the presence of these constituents and other flavonoids. 相似文献
26.
Antimicrobial peptides are known to selectively disrupt (highly charged) microbial membranes by asymmetrical incorporation into the outer layers. We present a physical basis for membrane-charge selectivity of cationic antimicrobial peptides. In particular, we provide a clear picture of how peptide-charge Q influences the asymmetrical insertion--one salient feature is the existence of an optimal peptide charge, at which selective insertion is optimized. Our results suggest that large Q is required for antimicrobial selectivity, consistent with experiments. 相似文献
27.
Aslanpanjeh Maryam Poursattar Marjani Ahmad Khalafy Jabbar Etivand Nasser 《Research on Chemical Intermediates》2020,46(1):165-177
Research on Chemical Intermediates - One-pot, three-component reaction of various aryl glyoxal monohydrates, 5-methylisoxazol-3-amine and 4-hydroxyquinolin-2(1H)-one in the presence of a catalytic... 相似文献
28.
Nouri Amrah Marjani Ahmad Poursattar Khalafy Jabbar Etivand Nasser 《Research on Chemical Intermediates》2020,46(6):3025-3036
Research on Chemical Intermediates - New 3-(2-aryl-6-nitro-1H-indol-3-yl)quinoline-2,4(1H,3H)-diones were synthesized, and good-to-excellent yields were achieved through one-pot, three-component... 相似文献
29.
Molecular dynamics simulations have been carried out to examine water flow in symmetric and asymmetric open and closed ends nanochannels with hydrophilic surfaces. The results are counterintuitive and the opposite of what is observed in macro-systems-closed channels fill faster with fluid than do their open counterparts. In addition, hybrid closed-open asymmetric channels fill up even faster. These results can be explained on the basis of the fluid-structure interaction that arises through the different vibrational behaviors of the surface molecules that are part of the wall forming these channels. Such effects are not expected to be of significance in macro-channels, and point to an important case where macro and nanochannels exhibit contrary behavior. Since these effects results from strong interactions between the fluid molecules and solid surface, one would not expect them with hydrophobic walls, and our simulations confirm such behavior. 相似文献
30.