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61.
Some novel ferrocenyl linked pyrazoline analogs were synthesized, well characterized, and evaluated for in vitro antiamoebic activity against HM1 : IMSS strain of Entamoeba histolytica. Most of the compounds exhibited higher antiamoebic activity with the IC50 value in the range of 0.12–1.20 μM, than the reference drug metronidazole, (IC50 value of 1.78 μM). Compound 9 showed the most promising antiamoebic activity (IC50 = 0.12 μM), concluding that these compounds hold immense potential to be employed as new antiamoebic agents. Also, being novel, they can be a solution to the increasing resistance that has posed a major problem globally. 相似文献
62.
Tahir Ali Khan Sultana Naseem Yasser Azim Shama Parveen Mohammad Shakir 《Transition Metal Chemistry》2007,32(6):706-710
A novel series of 16-membered binuclear complexes of octaazatetraimine ligand,
[M = MnII, CoII, NiII, CuII and ZnII; X = Cl or NO3] have been synthesized by metal template condensation reactions of o-phenylenediamine with N,N′-diacetylhydrazine in 1:1:1 molar ratio in methanol. The proposed stoichiometry and the bonding of the macrocyclic moiety
to metal ions along with the overall stereochemistry have been derived from the results of elemental analyses, magnetic susceptibility,
conductivity data and the spectral data revealed from FT-IR,
, ESI mass, UV–visible studies. An octahedral geometry has been envisaged for MnII, CoII, and NiII complexes while a slight distortion in octahedral geometry has been noticed for CuII complexes. The low conductivity data of all the complexes suggest their non-ionic nature. 相似文献
63.
64.
Maqsood Ahmed Sajida Noureen Philippe C. Gros Benoit Guillot Christian Jelsch 《Acta Crystallographica. Section C, Structural Chemistry》2011,67(8):o329-o333
The title compound, C16H16Br2O4S2, which is a precursor for the synthesis of oligothiophenes and their substituted homologues, was synthesized and its X‐ray crystal structure determined at 100 K. The experimental electron‐density parameters for the available atom types were transferred from the ELMAM2 database. The compound lies about an inversion centre, which coincides with the mid‐point of a C—C bond. The molecules in the crystal are linked by several types of weak interactions; the largest contact surfaces are for H...H and H...Br. 相似文献
65.
Farukh Arjmand Fatima Sayeed Shazia Parveen 《Journal of organometallic chemistry》2011,696(24):3836-3845
The chiral benzimidazole ligand, 1,2-Bis(1H-benzimidazol-2-yl)ethane-1,2-diol, L, exhibiting coordination mode with an oxygen atom of alcohol group directed towards the metal ion and another -OH group with different molecular axis directed away from the metal center was utilized as a building block for organotin complexes [C18H19N4O2SnCl], [C28H23N4O2SnCl] and [C52H42N4O2Sn2] (1-3). Complexes 1 and 3 exhibit a pentacoordinate geometry while the complex 2 reveals hexacoordinated environment around the Sn(IV) metal ions as evidenced by 119Sn NMR studies. The DNA binding ability of benzimidazole ligand and their organotin(IV) complexes 1-3 were examined by employing different biophysical methods. The absorption titration of the complexes with CT-DNA reveal significant hyperchromic effect together with strong bathochromic shift of 4-5 nm which infer substantial binding of the complexes with CT-DNA. The intrinsic binding constant Kb values of the complexes 1-3 were found to be 2.16 ± 0.04 × 104, 3.47 ± 0.04 × 104 and 4.60 ± 0.04 × 103 M−1, respectively, suggesting pronounced binding of complex 2 with DNA double helix. The mechanism of binding of the complexes was further ascertained by the interaction studies of these complexes with nucleotides (5′-GMP and 5′-TMP) using absorption spectroscopy suggesting a clear preference for 5′-GMP binding which was further authenticated by NMR (1H and 31P NMR) studies. 相似文献
66.
Varanasi SR Kumar P Masia M Demontis P Suffritti GB Yashonath S 《Physical chemistry chemical physics : PCCP》2011,13(23):10877-10884
Experimental ionic conductivity of different alkali ions in water shows markedly different dependences on pressure. Existing theories such as that of Hubbard-Onsager are unable to explain these dependences on pressure of the ionic conductivity for all ions. We report molecular dynamics investigation of potassium chloride solution at low dilution in water at several pressures between 1 bar and 2 kbar. Two different potential models have been employed. One of the models successfully reproduces the experimentally observed trend in ionic conductivity of K(+) ions in water over the 0.001-2 kbar range. We also propose a theoretical explanation, albeit at a qualitative level, to account for the dependence of ionic conductivity on pressure in terms of the previously studied Levitation Effect. It also provides a microscopic picture in terms of the pore network in liquid water. 相似文献
67.
Noureen S Caramori S Monari A Assfeld X Argazzi R Bignozzi CA Beley M Gros PC 《Dalton transactions (Cambridge, England : 2003)》2012,41(16):4833-4844
The first dithienylpyrrole (DTP)-based bipyridine ligands has been prepared and coordinated with ruthenium to give the corresponding homoleptic complexes. Bipyridine was bound at pyrrole (DTP(1)) or thiophene (DTP(2)) ring. A strong bathochromic effect was obtained by switching from pyrrole to thiophene for ligands and complexes. Interestingly the DTP(2) series offered a wide absorption window from UV to visible domain with an almost constant absorbance. These effects are due to a larger extent of delocalization as supported by DFT calculations and photophysical measurements. 相似文献
68.
S Jan A Wajid Khan S Parveen RA Khan A Saeed AJ Tanveer A Ali Shad 《Chemistry Central journal》2012,6(1):76
ABSTRACT: BACKGROUND: Aerva javanica (Burm. f.) Juss. ex Schult. (Amaranthacea) is traditionally used for the treatment of wound healings, cough, diarrhoea, ulcer and hyperglycaemia. The current study was aimed to fractionate and isolate bioactive compounds and ultimately to evaluate their anti-ulcereogenic potential. RESULTS: In order to achieve these aims, the fractionation, purifications and then biological potential determination of the isolated compounds was carried out. For purification purpose, initially extraction of the plant material was done with aqueous MeOH in the order of increasing polarity by using solvent-solvent extraction method. Phytochemical analysis revealed the presence of three compounds, 3-hydroxy-4 methoxybenzaldehyde (1), ursolic acid (2) and (E)-N-(4-hydroxy-3-methoxyphenethyl)-3-(4-hydroxy-3-ethoxyphenyl) acryl amide (3). Inhibition of urease activity of various fractions revealed that ethyl acetate fraction showed significant activity (P <0.05) as compared to other fractions. (E)-N-(4-hydroxy-3- methoxyphenethyl)-3-(4-hydroxy-3-ethoxyphenyl) acryl amide (3) showed marked anti ulcer activity (P <0.05). CONCLUSION: These results suggested the mild potential of A. javanica against ulcer. 相似文献
69.
Systematic study of the product((E(2_2~+)/E(2_1~+)) * B(E2)↑) through the asymmetric rotor model
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A systematic study of the product((E(2_2~+)/E(2_1~+))*B(E2)↑) is carried out in the major shell space Z=50-82,N=82-126 within the framework of the asymmetric rotor model where the asymmetry parameter γ0reflects change in the nuclear structure.A systematic study of the product((E(2+)/E(2+))*B(E2)↑) with neutron number N is also discussed.The product((E(2_2~+)/E(2_1~+))*B(E2)↑) provides a direct correlation with the asymmetry parameter γ0.The effect of subshells is visible in Ba-Gd nuclei with N 82,but not in Hf-Pt nuclei with N 104.We study,for the first time,the dependency of the product((E(2_2~+)/E(2_1~+))*B(E2)↑) on the asymmetry parameterγ0. 相似文献
70.
Muhammad Umer Faroque Sajida Noureen Shafaat Hussain Mirza Muhammad Nawaz Tahir Maqsood Ahmed 《Acta Crystallographica. Section C, Structural Chemistry》2019,75(1):46-53
Pyrimethamine is an antimalarial drug. The cocrystal salt form of pyrimethamine with 3,5‐dihydroxybenzoic acid in water solvent has been synthesized, namely 2,4‐diamino‐5‐(4‐chlorophenyl)‐6‐ethylpyrimidin‐1‐ium 3,5‐dihydroxybenzoate hemihydrate, C12H14ClN4+·C7H5O4?·0.5H2O. X‐ray diffraction data were collected at room temperature. Refinement of the crystal structure was carried out using the classical Independent Atom Model (IAM), while the electrostatic properties were studied by transferring electron‐density parameters from an electron‐density database. The Cl atom was refined anharmonically. The results of both refinement methods were compared. Topological analyses were carried out using Bader's theory of Atoms in Molecules (AIM). The three‐dimensional Hirshfeld surface analysis and the two‐dimensional fingerprint maps of individual molecules revealed that the crystal structures are dominated by H…O/O…H and H…H contacts. Other close contacts are also present, including weak C…H/H…C contacts. Charge transfer between the pyrimethamine and 3,5‐dihydroxybenzoic acid molecules results in a molecular assembly based on strong intermolecular hydrogen bonds. This is further validated by the calculation of the electrostatic potential based on transferred electron‐density parameters. The current work proves the significance of the transferability principle in studying the electron‐density‐derived properties of molecules in cases where high‐resolution diffraction data at low temperature are not available. 相似文献