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1.
Soltani Rad Mohammad Navid Behrouz Somayeh Mohammad-Javadi Mehdi Zarenezhad Elham 《Molecular diversity》2022,26(5):2503-2521
Molecular Diversity - The preparation, characterization and application of hydroxyapatite silica propyl bis aminoethoxy ethane cuprous complex (HASPBAEECC) as a novel hybrid nano-catalyst for... 相似文献
2.
3.
Biabangard Fatemeh Nazari Hadiseh Arefinia Reza 《Journal of Solid State Electrochemistry》2021,25(3):881-893
Journal of Solid State Electrochemistry - A stable suspension of nanopolyaniline (nPANI) particles can be used in various applications instead of a polyaniline film. The electrochemical behavior of... 相似文献
4.
Mark Edgar Dee Hayward Fatemeh Zeinali Shahzad Riaz George W. Weaver 《Magnetic resonance in chemistry : MRC》2020,58(2):170-185
A simple to use nuclear magnetic resonance analysis method has been tested on complex 1H, 19F, and 13C multiplets. This open-source line-shape analysis method analysis of total lineshape (ANATOLIA)1 provides some significant advantages over traditional assign-iterate methods of NMR spectral analysis by avoiding false minima and progressing optimisation to the global minimum. The target molecules are 1-perfluorotol-4-yl-2-perfluorotol-4-yl-oxymethyl-1H-benzimidazole (molecule-I) and 1-tetrafluoropyrid-4-yl-2-tetrafluoropyrid-4-yl-thio-1H-benzimidazole (molecule-II) which were produced as part of a family of fluorinated drug scaffolds prepared for anticancer and antiparasitic screening. Spectra display significant second-order effects with 1H Δδ = 3.68 and 4.67 Hz for the aromatic hydrogen “triplets”, with 19F 4JAA', 4JBB', 4JXX', and 4JYY' coupling constants range from +4.8 to −14.0 Hz and for 13C-isotopomers 19F Δδ of up to 111.56 Hz. A spin-system of six coupling nuclei (HaHbHcHd FYFY') was analysed in 12 s, a spin-system of nine coupling fluorine nuclei (AA'BB'CCC-YY') was analysed within 2 min, and 10 coupling nuclei (XX'YY'ZZZ-BB'-Hd) was optimised in 6 min using a laptop computer. ANATOLIA was also robust enough to be able to yield accurate spectral values from inaccurate input values. In both compounds, a fluorine–fluorine coupling constant was identified between the two fluoro-aromatic rings (FBB' and FYY') of +4.05 and +4.67 Hz and attributed to a through-space interaction. Ab initio structure optimisations and coupling constant calculations provided useful input data for spectral analysis. A modern 19F nuclear magnetic resonance spectrum of perfluorotoluene (octafluorotoluene) and analysis from 1975 was used as a test data set to assess ANATOLIA. 相似文献
5.
A simple one-pot procedure for the direct conversion of alcohols into azides using TsIm 总被引:1,自引:0,他引:1
A facile and efficient method for one-pot conversion of alcohols into azides using N-(p-toluenesulfonyl)imidazole (TsIm) is described. In this method, alcohols are refluxed with a mixture of NaN3, TsIm and triethylamine in the presence of catalytic amounts of tetra-n-butylammonium iodide (TBAI) in DMF affording the corresponding alkyl azides in good yields. This methodology is highly efficient for various structurally diverse alcohols with selectivity for ROH: 1° > 2° > 3°. 相似文献
6.
Mohammad Ali Zolfigol Iraj Mohammadpoor-BaltorkDavood Habibi BiBi Fatemeh MirjaliliAbdolhamid Bamoniri 《Tetrahedron letters》2003,44(44):8165-8167
Primary and secondary trimethylsilyl ethers were converted to their corresponding ethers in the presence Nafion-H® with good to excellent yields under mild and heterogeneous conditions. 相似文献
7.
8.
Majid M. Heravi Khadijeh Bakhtiari Negar M. Javadi Hossein A. Oskooie Fatemeh F. Bamoharram 《Monatshefte für Chemie / Chemical Monthly》2007,138(5):445-447
Summary. Acetylation of various alcohols and benzyl amine was tested in the presence of H6[PMo9V3O40], a mixed addenda heteropolyacid, in ethyl acetate under reflux condition. Phenols and anilines are not affected under the
reaction conditions. Selective transestrification of alcohols can be achieved in the presence of phenol and aniline derivatives
using this method. 相似文献
9.
Complexes between dextrans of different molar mass and bovine hemoglobin were synthesized by two different methods. In the alkylation method three and in the dialdehyde method, two hemoglobins are coupled on average to one dextran molecule. In both cases, the soluble hemoglobin-dextran complexes reversibly bind and release oxygen; the oxygen affinity is greater than that of free hemoglobin. Static and dynamic light scattering was used to determine the average molar mass Mu, the radius of gyration 〈S〉, and the hydrodynamic radius Rh of both the complexes and the single dextrans. Interpretation of these data is complicated due to the fact that the complexes are copolymers. When appropriate approximations are made, the results indicate that the complexes have a spherical shape and an internal structure of a multiple-chain network, where several dextrans are linked together by the hemoglobins. The number of single dextrans per complex increases as the molar mass of the single dextrans is decreased. The increment is greater in the dialdehyde than in the alkylation method. The probable reason is that in the dialdehyde method one hemoglobin can connect many dextrans simultaneously while in the alkylation method a hemoglobin is able to link maximally two dextrans. The ratio of the radius of gyration to the hydrodynamic radius decreases as the temperature is increased. This suggests a decrease of the solvent penetration length for the complexes and can be interpreted on the basis of the Deutsch-Felderhof theory for porous spheres. © 1994 John Wiley & Sons, Inc. 相似文献
10.
Saeed Yousefinejad Fatemeh Honarasa Samira Akbari Mohsen Nekoeinia 《液相色谱法及相关技术杂志》2020,43(15-16):580-588
AbstractSeparation of amino acids (AAs) and their simple and inexpensive determination/identification is an interesting topic in biological and protein science, different food industries, and drug factories. Also, the presentation of the chromatographic behavior of compounds in a predictive model can be effective to estimate the structural/chemical properties of analyte and mobile phases. In this work for the first time, retardation factor (RF) of 42 AAs in reversed-phase thin layer chromatography (RP-TLC) was modeled. Acetonitrile-sodium azide solution and 1,2 dioxane-sodium azide solution were two mobile phases which have been studied in this work. Results showed that the values of RF are correlated with the structural properties of AAs and these properties had some similarities and differences in two noted mobile phases. For the TLC data in two mobile phases, five parametric linear models were suggested (R2train = 0.93 and 0.97; R2test = 0.93 and 0.99). The models were also evaluated with different statistical approaches. It was shown that increasing the sum of geometrical distances between N and O in AAs causes decreasing their RF in RP-TLC using both mobile phases. Other structural effects of AAs on their separation in the desired RP-TLC system were also discussed. 相似文献