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131.
Somayeh Pirhadi Fereshteh Shiri Jahan B. Ghasemi 《Journal of the Iranian Chemical Society》2014,11(5):1329-1336
Comparative molecular field analysis (CoMFA) and comparative similarity indices analysis (CoMSIA) studies have been carried on a series of 2,4-dioxopyrimidine-1-carboxamides as acid ceramidase inhibitors. Two alignment rules for the compounds were defined using maximum common substructure and field fit. The best orientation was then searched by all-orientation search strategy, to minimize the effect of the initial orientation of the structures. The Kennard Stone algorithm was used to divide the entire set into training (25 compounds) and test (7 compounds) sets. Pharmacophore model identification was also performed using DISCOtech algorithm and refinement was carried out using GASP, to highlight important structural features that could be responsible for the inhibitory activity. All constructed models showed appropriate statistical parameters in terms of q 2 and r pred 2 . Based upon the information obtained from CoMFA, CoMSIA, and developed pharmacophore pattern, some key features that may be used to design new inhibitors for acid ceramidase have been identified. 相似文献
132.
Abouzar Roeintan Sayed Mojtba Moosavi Mohammad Navid Soltani Rad Somayeh Behrouz 《中国化学会会志》2015,62(12):1097-1104
The ‘click synthesis’ of some novel O‐substituted oximes, 5a – 5j , which contain heterocycle residues, as new analogs of ß‐adrenoceptor antagonists is described (Scheme 1). The synthesis of these compounds was achieved in four steps. The formation of (E)‐2‐(1H‐benzo[d]imidazol‐1‐yl)‐1‐phenylethanone oxime, followed by their reaction with 2‐(chloromethyl)oxirane, afforded mixture of oil compounds 3 and 4 , which by a subsequent tetra‐n‐butylammonium bromide (TBAB)‐catalyzed reaction with N H heterocycle compounds (Scheme 1), led to the target compounds 5a – 5j in good yields. 相似文献
133.
Selective aerobic oxidative coupling of thiols that are catalyzed by La(III)-substituted 5-oxopyrrolidine-2-carboxylic acid (Glp) immobilized on SBA-15 (SBA-15@Glp–La; SBA = Santa Barbara amorphous) was studied. Using SBA-15@Glp–La, the complete conversion was achieved at room temperature in the presence of air without producing any over-oxidized yields. SBA-15@Glp–La was prepared by post-grafting technique. 5-Oxopyrrolidine-2-carboxylic acid (Glp) condensation followed by La(III) impregnation caused this La(III)-grafted 5-oxopyrrolidine-2-carboxylic acid (Glp) to immobilize on SBA-15. This SBA-15@Glp–La catalyst shows excellent catalytic activity in the selective aerobic oxidative coupling of thiols. Effects of amount of the catalyst, polarity of the solvent, effects of substrate, and catalyst reusability were investigated. It has been observed that seven repetitive reaction cycles did not cause any appreciable loss in the catalytic activity of this catalyst. The catalyst characterization by scanning electron microscopy, energy-dispersive X-ray spectroscopy, X-ray diffraction, Fourier-transform infrared spectroscopy, thermal gravimetric analysis, transmission electron microscopy, inductively coupled plasma, elemental mapping, and N2 adsorption–desorption is reported. The procedure developed is heterogeneous and environmentally benign. 相似文献
134.
Mohammad Navid Soltani Rad Zeinab Asrari Somayeh Behrouz Gholam Hossein Hakimelahi Ali Khalafi‐Nezhad 《Helvetica chimica acta》2011,94(12):2194-2206
The ‘click synthesis’ of some oxiconazole analogs 5a – 5v having 1H‐1,2,3‐triazolyl residues by Huisgen cycloaddition was achieved in four steps (Scheme 1). Oximation of phenacyl chloride ( 1 ) followed by azidation of 2‐chloro‐1‐phenylethanone oxime ( 2 ) provided azido ketoxime 3 . The CuI‐catalyzed Huisgen cycloaddition of 3 with terminal alkynes gave the 4‐substituted (at the triazole) 2‐(1H‐1,2,3‐triazol‐1‐yl)‐1‐phenylethanone oximes 4a – 4i . The O‐alkylation of 4a – 4i with various alkyl halides resulted in the formation of the target molecules 5a – 5v in good yields. 相似文献
135.
A method was developed for the determination of gold ion in water samples using microextraction based on the ultrasound-assisted emulsification of solidified floating organic drops, followed by the flame atomic absorption spectrometry. N-(4-{4-[(anilinocarbothioyl)amino]benzyl}phenyl)-N-phenylthiourea was used as chelating agent. The parameters affecting the extraction and complex formation (including the type and volume of the extracting solvent, time of sonication and centrifugation, pH, amount of the chelating agent, and sample ionic strength) were optimized. Under the optimum conditions, the calibration graph is linear in the range from 1.5 to 400 ng mL?1, with a limit of detection of 0.45 ng mL?1. The relative standard deviation for ten replicate determinations of gold ion in a concentration of 175 ng mL?1 was 1.7%. The procedure was successfully applied to the determination of gold in water samples, in pharmaceutical and synthetic samples, and in a standard reference material. Figa
The schematic procedure of the ultrasound-assisted emulsification solidified floating organic drop microextraction is shown in above figure from A to E. 相似文献
136.
Hayedeh Bagheri Sadeghi Atefeh Tamaddon Hadi Afifinia Nasim Almasian Fatemeh Bozorgvar Somayeh Mollaei 《Electroanalysis》2011,23(10):2472-2478
A new chromium(III) PVC membrane sensor incorporating p‐tertiary‐butyl calix[4]arene as ionophore, potassium tetrakis as additive and dibutyl phthalate (DBP) as plasticizer was constructed. The electrode exhibited an excellent potentiometric response over a wide concentration range of 1.0×10?7–1.0×10?1 M with a Nernstian slope of 20±0.5 mV per decade. The detection limit was 5.0×10?8 M. The electrode showed a better performance over a pH range of 3.0–8.0, and had a short response time of about <15 s.The electrode was successfully applied to potentiometric titration of Cr (III) with EDTA and for direct determination of chromium(III) in waste water. 相似文献
137.
Ana Sanchez‐Sanchez Somayeh Akbari Angel J. Moreno Federica Lo Verso Arantxa Arbe Juan Colmenero Jos A. Pomposo 《Macromolecular rapid communications》2013,34(21):1681-1686
Inspired by the multifunctionality of vitamin D‐binding protein and the multiple transient‐binding behavior of some intrinsically disordered proteins (IDPs), a polymeric platform is designed, prepared, and characterized for combined delivery of dermal protective and anticancer bioactive cargos on the basis of artificial single‐chain nano‐objects mimicking IDPs. For the first time ever, simultaneous delivery of folic acid or vitamin B9, and hinokitiol, a relevant natural bioactive compound that exhibits anticancer activity against human malignant melanoma cells, from these multidirectionally self‐assembled unimolecular nanocarriers is illustrated.
138.
Farhad Shirini Somayeh Akbari-Dadamahaleh Ali Mohammad-Khah Ali-Reza Aliakbar 《Comptes Rendus Chimie》2013,16(3):207-216
Rice husk, as a green and cheap reagent, can be used for the promotion of the synthesis of 12-aryl -8, 9,10,12-tetrahydrobenzo[α] xanthen-11-one derivatives (ATXOs) via three-component reaction of aldehydes, 2-naphthol and 5,5-dimethyl-1,3-cyclohexadione (dimedone) under solvent-free conditions. This catalyst can also be used for the preparation of quinoxaline derivatives in a mixture of H2O and CH3CN at 50 °C. The present methodology offers several advantages such as high yields, simple procedure, low cost, short reaction times, mild reaction conditions and use of a green, cheap and reusable catalyst. 相似文献
139.
Gholam Hossein Rounaghi Somayeh Tarahomi Massoumeh Mohajeri 《Journal of inclusion phenomena and macrocyclic chemistry》2009,63(3-4):319-325
The complexation reaction of macrocyclic ligand, dibenzo-24-crown-8 (DB24C8) with Y+3 cation was studied in some binary mixtures of methanol (MeOH), ethanol (EtOH), acetonitrile (AN) and tetrahydrofuran (THF) with dimethylformamide (DMF) at different temperatures using the conductometric method. The conductance data show that in all solvent systems, the stoichiometry of the complex formed between DB24C8 and Y+3 cation is 1:1 (ML). The stability order of (DB24C8.Y)+3 complex in pure non-aqueous solvents was found to be: AN > EtOH > MeOH > DMF. A non-linear behaviour was observed for changes of log Kf of (DB24C8.Y)+3 complex versus the composition of the binary mixed solvents, which was explained in terms of solvent–solvent interactions and also the heteroselective solvation of the species involved in the complexation reaction. The obtained results show that the stability of (DB24C8.Y)+3 complex is sensitive to the mixed solvents composition. The values of thermodynamic parameters (?H°c and ?S°c) for formation of (DB24C8.Y)+3 complex were obtained from temperature dependence of the stability constant using the van’t Hoff plots. The results show that in most cases, the (DB24C8.Y)+3 complex is enthalpy destabilized but entropy stabilized and the values and also the sign of thermodynamic parameters are influenced by the nature and composition of the mixed solvents. 相似文献
140.
Mohammad Navid Soltani Rad Ali Khalafi‐Nezhad Somayeh Behrouz 《Helvetica chimica acta》2009,92(9):1760-1774
The syntheses of some novel carboacyclic nucleosides, 17a – 17o , containing oxiconazole‐like scaffolds, are described (Schemes 1–3). In this series of carboacyclic nucleosides, pyrimidine as well as purine and other imidazole derivatives were employed as an imidazole successor in oxiconazole. These compounds could be prepared in good yields by using two different strategies (Schemes 1 and 2). Due to Scheme 1, the N‐coupling of nucleobases with 2‐bromoacetophenones was attained for 18a – 18e , and their subsequent oximation affording 19a – 19e and finally O‐alkylation with diverse alkylating sources resulted in the products 17a – 17g, 17n , and 17o . In Scheme 2, use of 2‐bromoacetophenone oximes 20 , followed by N‐coupling of nucleobases, provided 19f – 19j whose final O‐alkylation produced 17h – 17m (Scheme 2). For the rational interpretation of the dominant formation of (E)‐oxime ethers rather than (Z)‐oxime isomers, PM3 semiempirical quantum‐mechanic calculations were discussed and the calculations indicated a lower heat of formation for (E)‐isomers. 相似文献