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1.
Behforouz M Haddad J Cai W Arnold MB Mohammadi F Sousa AC Horn MA 《The Journal of organic chemistry》1996,61(19):6552-6555
The novel 7-(N-formyl-, 7-(N-acetyl-, and 7-(N-isobutyrylamino)-2-methylquinoline-5,8-diones were synthesized in excellent overall yields in three steps via the nitration of the commercially available 8-hydroxy-2-methylquinoline followed by a reduction-acylation step and then oxidation. Acid hydrolysis of 7-(N-acetylamino)-2-methylquinoline-5,8-dione (14a) afforded the novel 7-aminoquinoline-5,8-dione 7 in excellent yields. Due to our efficient preparation of dione 14a, we now report a short and practical method for the total synthesis of the potent antitumor agent lavendamycin methyl ester (1b) with an excellent overall yield. 相似文献
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Bahador Abolpour Roozbeh Abolpour Arash Shamseddini Saideh Kamyabi Farahnaz Hamzehee 《Research on Chemical Intermediates》2013,39(2):681-692
In this paper, the enthalpy-concentration method was applied in order to model a steady-state continuous methanol–water mixture distillation column. This work includes three steps; first, to develop a code in MATLAB v.7.6 to apply to the mathematical model of the column. The second step is to simulate the column using HYSIS v.3.2. While the third is the calculation of the optimized reflux ratio to minimize the operating cost. For a distillation tower such as the methanol–water splitter in this study, there are relatively few degrees of freedom that can be manipulated in order to minimize operating costs; the reflux ratio can influence the steady-state operating point and therefore the daily costs. In this paper, we have discussed the trade-offs between reflux ratios and operating costs. A correlation is derived to define the optimum value of the reflux ratio as an exponential function of a certain economic parameter of energy prices and depreciation costs. We demonstrate that, at low energy prices or high equipment depreciation costs, the optimum reflux factor is high. 相似文献
3.
Farahnaz Nourmohammadian Mahnaz Davoudzadeh Gholami 《Phosphorus, sulfur, and silicon and the related elements》2013,188(2):340-346
A convenient and efficient, regioselective, solvent-free procedure has been developed to react 2,6-dihydroxyanthraquinone, dialkyl acetylenedicarboxylates, and triphenylphosphine in one-pot, to afford novel phosphanylidene anthracenyl derivatives 3a-c, which at 90°C due to intramolecular nucleophilic attack formed novel phosphanylidene anthra[2,1-b]furans 4a–c in good yield. 相似文献
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Here, the synthesis of two novel series of dichromophoric cyanine dyes were reported. The first series of novel bis-azacyanine dyes 3a–d was afforded by reaction of 2-(1,3,3-trimethyle indoline-2-ylidene)acetaldehyde with diaminoaromatics, and the second series of novel bis-diazacyanine dyes 4a–d was obtained using quaternization of an amine group in disazo compounds, which were produced by the reaction of disazoaromatics with 2-methylene-1,3,3-trimethyle indoline. The products were identified by 1H NMR, 13C NMR, infrared, UV-vis, and mass spectroscopy. 相似文献
6.
Nour-Mohhamadi F Nguyen SD Boschloo G Hagfeldt A Lund T 《The journal of physical chemistry. B》2005,109(47):22413-22419
The oxidative degradation rate, kdeg, of the solar cell dye (Bu4N+)2[Ru(dcbpyH)2(NCS)2]2-, referred to as N719 or [RuL2(NCS)2], was obtained by applying a simple model system. Colloidal solutions of N719-dyed TiO2 particles in acetonitrile were irradiated with 532-nm monochromatic light, and the sum of the quantum yields for the oxidative degradation products [RuL2(CN)2], [RuL2(NCS)(CN)], and [RuL2(NCS)(ACN)], Phideg, was obtained at eight different light intensities in the range of 0.1-16.30 mW/cm2 by LC-UV-MS. The Phideg values decreased from 3.3 x 10-3 to 2.0 x 10-4 in the applied intensity range. By using the relation kdeg = Phidegkback and back electron-transfer reaction rates, kback, obtained with photoinduced absorption spectroscopy, it was possible to calculate an average value for the oxidative degradation rate of N719 dye attached to TiO2 particles, kdeg = 4.0 x 10-2 s-1. The stability of N719 dye during solar cell operation was discussed based on this number, and on values of the electron-transfer rate between [Ru(III)L2(NCS)2] and iodide ion that are available in the literature. 相似文献
7.
Hossein A. Oskooie Majid M. Heravi Maryam H. Tehrani Farahnaz K. Behbahani Omid M. Heravi 《Phosphorus, sulfur, and silicon and the related elements》2013,188(7):1729-1737
In this article, a mild and efficient protocol for the trimethylsilylation of various aliphatic and benzylic alcohols and phenols with trimethylsilyl chloride using a catalytic amount of ferric perchlorate at room temperature and relatively short reaction times in good to excellent yields is reported. Direct acetylation of trimethylsilyl ethers catalyzed with Fe(ClO 4 ) 3 .6H 2 O(0.02 mmol)/Fe(ClO 4 ) 3 SiO 2 (0.2 g) using acetic anhydride at ambient temperature is also reported. 相似文献
8.
HERAVI Majid M. BEHBAHANI Farahnaz K. OSKOOIE Hossien A. BAMOHARRAM Fatemeh F. 《中国化学》2008,26(12):2150-2154
A simple and efficient method has been developed for the synthesis of β-amino alcohols by ring opening of epoxides in the presence of a catalytic amount of H14[NaP5W29MoO110] at room temperature under solvent-free conditions. The reaction works well for both aromatic and aliphatic amines. 相似文献
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Ehsan Karimi Meisam Habibi Mahdi Ebrahimi Ali Mehrafarin Farahnaz Khalighi-Sigaroodi 《Natural product research》2018,32(16):1991-1995
The antioxidant activities of crude extract fractions using Hexane, Chloroform, Ethyl Acetate, Butanol and Water of Clematis orientalis and Clematis ispahanica were investigated. 1,1-diphenyl-2-picryl-hydrazyl (DPPH) assay and the ferric reducing/antioxidant potential (FRAP) were used to evaluate the antioxidant capacity. The total phenolics were found to be 4.37–9.38 and 1.32–11.37 mg gallic acid equivalents (GAE)/g in different fractions for C. orientalis and C. ispahanica, respectively. The ethyl acetate fraction of C. orientalis and chloroform fraction of C. ispahanica showed the highest DPPH and FRAP activities at a concentration of 300 μg/mL. The predominant phenolic compounds identified by HPLC in C. orientalis were Resorcinol (603.5 μg/g DW) in chloroform fraction and Ellagic acid (811.7 μg/g DW) in chloroform fraction of C. ispahanica. 相似文献
10.
Wojciech Smuek Przemysaw Siejak Farahnaz Fathordoobady ukasz Masewicz Yigong Guo Magorzata Jarzbska David D. Kitts Przemysaw ukasz Kowalczewski Hanna Maria Baranowska Jerzy Stangierski Anna Szwajca Anubhav Pratap-Singh Maciej Jarzbski 《Molecules (Basel, Switzerland)》2021,26(19)
The use of natural surfactants including plant extracts, plant hydrocolloids and proteins in nanoemulsion systems has received commercial interest due to demonstrated safety of use and potential health benefits of plant products. In this study, a whey protein isolate (WPI) from a byproduct of cheese production was used to stabilize a nanoemulsion formulation that contained hempseed oil and the Aesculus hippocastanum L. extract (AHE). A Box–Behnken experimental design was used to set the formulation criteria and the optimal nanoemulsion conditions, used subsequently in follow-up experiments that measured specifically emulsion droplet size distribution, stability tests and visual quality. Regression analysis showed that the concentration of HSO and the interaction between HSO and the WPI were the most significant factors affecting the emulsion polydispersity index and droplet size (nm) (p < 0.05). Rheological tests, Fourier transform infrared spectroscopy (FTIR) analysis and L*a*b* color parameters were also taken to characterize the physicochemical properties of the emulsions. Emulsion systems with a higher concentration of the AHE had a potential metabolic activity up to 84% in a microbiological assay. It can be concluded from our results that the nanoemulsion system described herein is a safe and stable formulation with potential biological activity and health benefits that complement its use in the food industry. 相似文献