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51.
Jumat Salimon Nadia Salih Emad Yousif Ayad Hameed Ayad Kreem 《Arabian Journal of Chemistry》2010,3(4):205-210
In the present study a new acridone derivatives were synthesized. The newly synthesized compounds were characterized by IR, NMR and C, H, N, S analyses. All newly synthesized compounds were screened for their antibacterial (Staphylococcus aureus, Streptococcus viridans and Escherichia coil) and antifungal (Gibberela, Cercospora arachidicola, Physolospora piricola and Fusarium oxysporum) studies. The results revealed that all synthesized compounds have a significant biological activity against the tested microorganisms. 相似文献
52.
Salih S. Al-Juaid Colin Eaborn Paul D. Lickiss J. David Smith Kayumars Tavakkoli Alexander D. Webb 《Journal of organometallic chemistry》1996,510(1-2):143-151
Mercury compounds of the types HgR1R (R1 = C(SiMe3)3; R = Me, iPr, Bu, tBu or Ph) and HgR2R(R2 = C(SiMe2Ph)3; R = Me, Bu, CH2Ph or Ph) have been prepared. Those containing R1 were made by reactions of the bromides HgR1Br with the Grignard reagents MgRX, and those containing R2 by reaction of HgR2Cl with LiR or, for R = CH2Ph, with Mg(CH2Ph)Cl. Replacement of one R group in HgR2 by the bulky R1 or R2 group leads to a large increase in thermal stability, a marked shift in the 199Hg resonance to lower frequency and an increase in the coupling constant 1J(13C---199Hg) for the Hg---R bond. The compound HgR2Cl does not react further with LiR2 in tetrahydrofuran, but with LiR1 gives HgR1R2; the arrangement of the SiMe2Ph groups in the latter in solution in CH2C12 at low temperature appears to be different from that in the solid. 相似文献
53.
Ala'a K. Abdul-Sada Salih Al-Juaid Anthony M. Greenway Peter B. Hitchcock Matthew J. Howells Kenneth R. Seddon Thomas Welton 《Structural chemistry》1990,1(4):391-394
The crystal and molecular structures of [Me2Etim]Cl, [Me2Etim]2[CoCl4], and [Me2Etim]2[NiCl4] ([Me2Etim]+ = 1,2-dimethyl-3-ethylimidazolium cation) all contain evidence that the H4 and H5 protons of the imidazolium cation enter into hydrogen bonds; the implications of this observation for the interactions in room-temperature chloroaluminate(III) ionic liquids are considered. 相似文献
54.
An atomic absorption spectrophotometric method for the microdetermination of chlorine or bromine in organic compounds is described; it is based on oxygen flask combustion to yield chloride or bromide, which is then reacted with an excess of solid silver chromate, followed by collection of the combined unreacted silver chromate and chloride or bromide preipitate and AAS determination of the free chromate (equivalent of the chloride or bromide originally present) at 358.2 nm. The method was applied satisfactorily to a wide range of chlorine or bromine containing organic compounds with an average absolute error of ± 0.23 and a coefficient of variation (seven determinations) of better than 2%. 相似文献
55.
Salih Ilhan Hamdi Temel Recep Ziyadanogullari Memet Sekerci 《Transition Metal Chemistry》2007,32(5):584-590
A new macrocyclic ligand, 1,3,5-triaza-2,4:7,8:15,16-tribenzo-9,15-dioxacycloheptadeca-1,5-diene (L) was synthesized by reaction
of 2,6-diaminopyridine with 1,4-bis(2-carboxyaldehydephenoxy)butane. Then, its CuII, NiII, PbII, CoIII and LaIII complexes were synthesized by the template effect by reaction of 2,6-diaminopyridine and 1,4-bis (2-carboxyaldehydephenoxy)butane and Cu(NO3)2 · 3H2O, Ni(NO3)2 · 6H2O, Pb(NO3)2, Co(NO3)2 · 6H2O, La (NO3)3 · 6H2O, respectively. The ligand and its metal complexes were characterized by elemental analysis, IR, 1H- and 13C-n.m.r., UV-vis spectra, magnetic susceptibility, thermal gravimetric analysis, conductivity measurements and mass spectra.
All complexes are diamagnetic and the CuII complex is binuclear. The CoII complex was oxidised to CoIII. 相似文献
56.
Telhat??zdo?anEmail author Metin?Orbay Salih?De?irmenci 《Journal of mathematical chemistry》2005,37(1):27-36
Using the definition of STOs in terms of BTOs, we have presented analytical formula for two-center overlap integrals. The obtained formula contains generalized binomial coefficients and Mulliken integrals Ak and Bk. Taking into account the recent advances on the efficient calculation of Mulliken integrals (Harris, Int. J. Quantum Chem., 100 (2004) 142), we have obtained many more satisfactory results for two-center overlap integrals, for arbitrary quantum numbers, scaling parameters, and location of atomic orbitals.PACS No: 31.15.+qAMS Subject Classification: 81V55, 81–08 相似文献
57.
Hamdi Temel Hüseyin Alp Salih İlhan Berrin Ziyadanoğulları İsmail Yılmaz 《Monatshefte für Chemie / Chemical Monthly》2007,138(12):1199-1209
Summary. La(III), Cu(II), Ni(II), and Zn(II) metal complexes with a novel quadridentate Schiff base derived from 1,7-bis(2-formylphenyl)-1,4,7-trioxaheptane and 2-aminothiophenol were synthesized and characterized by
microanalytical data, elemental analysis, magnetic measurements, 1H NMR, 13C NMR, UV-Vis, IR, mass spectra, cyclic voltammetric and conductance measurements. The extractability of divalent cations
was evaluated as a function of relationship between distribution ratio of the metal and pH or ligand concentration. The highest extraction percentage of Cu2+ and Ni2+ showed pH 7.0 and 6.4. It was concluded that the ligand can effectively be used in solvent extraction of copper(II) and nickel(II)
from the aqueous phase to the organic phase. 相似文献
58.
Six new macrocyclic complexes were synthesized by a template reaction of 1,4-bis(2-formylphenoxy)butane with diamines and Cu(NO3)2·3H2O and their structures were proposed on the basis of elemental analysis, FT-IR, UV-Vis, magnetic susceptibility measurements, molar conductivity measurements and mass spectra. The metal to ligand molar ratios of the Cu(Ⅱ) complexes were found to be 1 : 1. The Cu(Ⅱ) complexes are 1 : 2 electrolytes as shown by their molar conductivities (∧m) in DMF at 10^-3 mol·L^-1. Due to the existence of free ions the Cu(Ⅱ) complexes are electrically conductive. Their configurations were proposed to be probably distorted octahedral. 相似文献
59.
Abdalrhaman M. Salih Fahad Al-Qurainy Mohammad Nadeem Mohamed Tarroum Salim Khan Hassan O. Shaikhaldein Abdulrahman Al-Hashimi Alanoud Alfagham Jawaher Alkahtani 《Molecules (Basel, Switzerland)》2021,26(24)
Juniperus procera is a natural source of bioactive compounds with the potential of antitumor, antimicrobial, insecticidal, antifungal, and antioxidant activities. An optimization method was developed for total phenolic content (TPC), total flavonoid content (TFC), and total tannin content (TTC) in leaf and seed extract of Juniperus procera. Organic solvents (methanol (99.8%), ethanol (99%), and acetone (99.5%)), and deionized water (DI) were used for extraction. The estimation of TPC, TFC, and TTC in plant materials was carried out using UV-spectrophotometer and HPLC with the standards gallic acid, quercetin, and tannic acid. Recovery of TPC in leaf extract ranged from 2.9 to 9.7 mg GAE/g DW, TFC from 0.9 to 5.9 mg QE/g DW, and TTC ranged from 1.5 to 4.3 mg TA/g DW while the TPC value in the seed extract ranged from 0.53 to 2.6 mg GAE/g DW, TFC from 0.5 to 1.6 mg QE/g DW, and TTC ranged from 0.5 to 1.4 mg TA/g DW. This result revealed that methanol is the best solvent for recovery of the TPC value (9.7 mg) from leaf extract in comparison to other solvents. Ethanol recorded the highest result of TFC (5.9 mg) in leaf extract among the solvents whereas acetone was the best for TTC yield recovery from leaf extract (4.3 mg). In the case of the seed extract, ethanol was the best solvent for both TPC (2.6 mg), and TFC (1.6 mg) recovery in comparison to other solvents. Total tannin content in methanol resulted in significant recovery from seed extract (1.4 mg). Separation and quantification of gallic acid, quercetin, and tannic acid in plant materials were undertaken using HPLC. Gallic acid in leaf and seed of J. procera ranged from 6.6 to 9.2, 6.5 to 7.2 µg/g DW, quercetin from 6.3 to 18.2, 0.9 to 4.2 µg/g DW, and tannic acid from 16.2 to 29.3, 6.6 to 9.3 µg/g DW, respectively. Solvents have shown a significant effect in the extraction of phenolic compounds. Moreover, phytochemicals in plant materials were identified using GC-MS and resulted in very important bioactive compounds, which include anti-inflammatory, antibacterial, and antitumor agents such as ferruginol, phenanthrene, and n-hexadecanoic acid. In conclusion, the optimal solvent for extraction depends on the part of the plant material and the compounds that are to be isolated. 相似文献
60.
A. Y Obaid A. O. Alyoubi A. A. Samarkandy S. A. Al-Thabaiti S. S. Al-Juaid A. A. El-Bellihi El-H. M. Deifallah 《Journal of Thermal Analysis and Calorimetry》2000,61(3):985-994
The thermal decomposition of copper(II) acetate monohydrate was studied in air and nitrogen atmospheres by means of DTA-TG
and SEM measurements. The kinetics of the thermal decomposition steps in air was studied by using isothermal and non-isothermal
thermogravimetric techniques. The results are discussed in terms of various reaction interface models and different techniques
of computational analysis of non-isothermal data. The activation parameters, calculated by using a composite method of integral
analysis of non-isothermal data, revealed not only their independence from the heating rate and fractional reaction, but also
a better correlation and agreement with the results obtained under isothermal conditions.
This revised version was published online in July 2006 with corrections to the Cover Date. 相似文献