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61.
Zeinab Ahmadvand Mehdi Bayat Mohammad Ali Zolfigol 《Journal of computational chemistry》2020,41(26):C1-C1
Pd-PEPPSI type complexes are widely used as precatalyst in a variety of organic reactions, including the Negishi, Kumada and Suzuki-Miyaura cross-coupling reactions. The aim of this research is to determine potential proposed reaction pathways 1, 2, or 2′ (See Schemes 1 and S1–S4 ) for Pd-PEPPSI precatalyst activation in the presence of ethylene glycol as a solvent also in the gas phase at Cam-B3LYP-D3 method nominated among eight DFT methods examined. There is also investigation into the impact of promoter bases (NaOEt, NaOiPr, NaOtBu) on precatalyst activation of Pd-PEPPSI. Eventually, the most favorable proposed reaction pathway and promoter base for reducing Pd(II) to Pd(0) are predicted computationally. Notably, our findings are consistent with the organ Pd-PEPPSI type complexes that offer increased catalytic activity and provide basic information in the presence of solvents designing the monoligated Pd(0)-solvent. 相似文献
62.
Behnam Mahdavi Sogand Paydarfard Mohammad Mahdi Zangeneh Samaneh Goorani Niloofar Seydi Akram Zangeneh 《应用有机金属化学》2020,34(1):e5248
In recent decades, nanotechnology is growing rapidly owing to its widespread application in medical science. The aim of the experiment was the evaluation of cytotoxicity, antioxidant, antibacterial, antifungal, and cutaneous wound healing activities of green synthesized manganese nanoparticles using Ziziphora clinopodioides Lam leaves (MnNPs@ZC). The synthesized MnNPs@ZC were characterized using different techniques including UV–Vis., FT-IR spectroscopy, X-ray diffraction (XRD), scanning electron microscopy (SEM), and energy dispersive X-ray spectrometry (EDS). According to the XRD analysis, 48.10 nm was measured for the crystal size of nanoparticles. SEM images exhibited a uniform spherical morphology and size in the range of 47.58 to 70.26 nm for the biosynthesized nanoparticles. MnNPs@ZC revealed excellent non-cytotoxicity effect against human umbilical vein endothelial cells, antioxidant activity against DPPH, antibacterial properties against Gram-negative bacteria (Salmonella typhimurium, Pseudomonas aeruginosa, and Escherichia coli O157:H7) and Gram-positive bacteria (Streptococcus pneumonia, Staphylococcus aureus, and Bacillus subtilis), and antifungal potentials against Candida glabrata, Candida albicans, Candida guilliermondii, and Candida krusei. Also, use of MnNPs@ZC ointment decreased significantly (p ≤ 0.01) the wound area, total cells, neutrophil, and lymphocyte and raised significantly (p ≤ 0.01) the wound contracture, hydroxyl proline, hexosamine, hexuronic acid, fibrocyte, and fibrocytes/fibroblast rate compared to other groups in experimental animals. In conclusion, synthesized MnNPs@ZC indicated antibacterial, antifungal, non-cytotoxicity, antioxidant, and cutaneous wound healing effects in a dose-depended manner. After confirming in the clinical trials, these nanoparticles can be used in human for the treatment of cutaneous and infectious diseases. 相似文献
63.
Mohammad Sadegh Asgari Parviz Rashidi Ranjbar Rahmatollah Rahimi Mohammad Mahdavi 《应用有机金属化学》2020,34(2):e5279
Cyclocarbopalladation/cross-coupling cascade intramolecular Heck–Suzuki–Miyaura reactions is applied for the first time by palladium immobilized on pyridine-imidazolium ionic liquid supported magnetic iron oxide nanoparticle catalyst (denoted Pd@Py-IL-SPION) for the last step to synthesize trisubstituted arylidene–isoquinolinones derivatives having Combretastatin skeleton. The reaction is performed via propargylamide intermediates prepared by Ugi 4-CR reactions, which undergoes intramolecular Heck–Suzuki–Miyaura domino reaction to produce the desired trisubstituted arylidene-isoquinolinones. The method shows full regio- and stereoselectivity derives from the particular Pd-catalyzed syn-insertion of triple bond. 相似文献
64.
The present research confirms the capacity of aqueous extract of Boswellia serrata grown under in vitro condition for the green synthesis of gold nanoparticles (AuNPs). Also, we showed the cytotoxicity, antioxidant, and anti-acute myeloid leukemia properties of AuNPs compared to mitoxantrone in a leukemic mouse model. The synthesized AuNPs were characterized using several techniques including XRD, TEM, FE-SEM, UV–Vis, and FT-IR. From the XRD pattern, four distinct diffraction peaks at 38.2°, 44.2°, 64.7° and 77.4° are indexed as (111), (200), (220) and (311) planes of FCC metallic gold. TEM and FE-SEM images revealed an average diameters of 15–30 nm for the nanoparticles. FT-IR findings offered antioxidant compounds in the nanoparticles were the sources of reducing power, reducing gold ions to AuNPs. UV–Vis revealed an absorption band at 536 nm that is related to the surface plasmon resonance of AuNPs. In vivo design, induction of acute myeloid leukemia was done by DMBA in 75 mice. Then, the mice were randomly divided into six subgroups, including untreated, control, HAuCl4, B. serrata, AuNPs, and mitoxantrone. AuNPs (In the dose of 1 mg/kg body weight) similar to mitoxantrone, significantly (p ≤ 0.05) increased the platelet, lymphocyte, and RBC parameters and the anti-inflammatory cytokines (IL4, IL5, IL10, IL13, and IFNα) and reduced the weights and volumes of liver and spleen and their sub-compartment, the total WBC, blast, monocyte, neutrophil, eosinophil, and basophil counts, and the pro-inflammatory cytokines (IL1, IL6, IL12, IL18, IFNY, and TNFα) as compared to the untreated mice. By quantitative Real-Time PCR, S1PR1 and S1PR5 mRNA expression in lymphocytes were significantly (p ≤ 0.05) increased by treating the leukemic mice with the AuNPs and mitoxantrone. In vitro design, AuNPs similar to mitoxantrone had low cell viability dose-dependently against Human HL-60/vcr, 32D-FLT3-ITD, and Murine C1498 cell lines without any cytotoxicity on HUVEC cell line. Besides, the DPPH assay showed similar antioxidant potentials for AuNPs and mitoxantrone. In conclusion, the results of this research indicated the excellent capacity of synthesized gold nanoparticles using B. serrata leaf aqueous extract in the treatment of acute myeloid leukemia in leukemic mice. 相似文献
65.
Milad Kazemnejadi Seyyedeh Ameneh Alavi G. Zinat Rezazadeh Mohammad Ali Nasseri Ali Allahresani Mohsen Esmaeilpour 《应用有机金属化学》2020,34(2):e5388
Cu(II) Schiff base complex supported on Fe3O4@SiO2 nanoparticles was employed as a magnetic nanocatalyst (nanocomposite) with a phase transfer functionality for the one-pot preparation of α-aminonitriles (Strecker reaction). The desired α-aminonitriles were obtained from the reaction of aromatic or aliphatic aldehydes, aniline or benzyl amine, NaCN, and 1.6 mol% of the catalyst in water at room temperature and good to excellent yields were obtained for all substrates. The catalyst was characterized analytically and instrumentally including Fourier-transform infrared spectroscopy, X-ray diffraction, thermogravimetric, nuclear magnetic resonance, energy-dispersive X-ray spectroscopy, inductively coupled plasma spectroscopy, vibrating-sample magnetometry analysis, dynamic light scattering, Brunauer–Emmett–Teller surface area, field emission scanning electron microscopy, and transmission electron microscopy analyses. The reaction mechanism was investigated, in which the performance of the catalyst as a phase transition factor seems to be probable. The catalyst showed high activity, high turnover frequency (TOF)s, significant selectivity, and fast performance toward the Strecker synthesis. The nanocatalyst can be readily and quickly separated from the reaction mixture with an external magnet and can be reused for at least seven successive reaction cycles without significant reduction in efficiency. 相似文献
66.
One-pot synthesis of substituted chromeno[3,4-b]quinoline derivatives was developed by three-component reaction of aldehydes, dimedone or 1,3-cyclohexadione, and 4-aminocoumarin in the presence of nicotinic acid-supported cobalt ferrite [CoFe2O4@SiO2@Si(CH2)3Cl@NA] as a novel magnetic catalyst in chloroform at reflux conditions. Nicotinic acid-supported cobalt ferrite was characterized via Fourier transform infrared spectroscopy, X-ray diffraction, thermal gravimetric analysis, scanning electron microscopy, high-resolution transmission electron microscopy, energy-dispersive X-ray spectroscopy, and vibrating sample magnetometry. Moreover, the catalyst could be easily recovered by magnetic separation and recycled up to five times without significant loss of its catalytic activity. The products formed in excellent yields over appropriate reaction times under environmentally friendly conditions. High efficiency and easy isolation of the catalyst from products by simple magnetic attraction are some of the considerable advantages of this procedure. 相似文献
67.
A ligand-free, CuI-catalyzed protocol was developed for the one-step preparation of Michael adducts of aromatic thiols in high yields by reacting a mixture of an aryl halide and an electron-deficient alkene with sodium iso-propyl xanthogenate. 相似文献
68.
Saba Hemmati Mohammad Yousefi Mirmehdi Hashemi Salehi Mahdis Amiri Malak Hekmati 《应用有机金属化学》2020,34(8):e5653
This paper develops a green method for in situ decorated of palladium nanoparticles over Fe3O4 nanoparticles, by utilizing Strawberry fruit extract and ultrasound irradiations, with no use of any toxic reducing agent. The structure's characterization is represented via diverse analytical methods such as FT-IR, FE-SEM, TEM, WDX, ICP, EDS and XXPS. Catalytic efficiency of magnetic Fe3O4@Strawberry/Pd nanocatalyst is investigated in production of different biphenyls with good turnover frequencies (TOF) and turnover numbers (TON) through Suzuki coupling reactions. Furthermore, the catalyst could be recovered and reused 7 runs without considerable palladium leaching or alteration in its performance. 相似文献
69.
In this study, quinazolinone derivatives have been synthesized via a suitable and efficient procedure by one-potmulti-component reactions of 3-amino-1,2,4-triazole or 2-aminobenzimidazole, dimedone and aromatic aldehydes in the presence of Fe3O4@TiO2-IL as nanocatalyst under solvent-free condition. The products were prepared in good to excellent yields using Fe3O4@TiO2-IL magnetic nanocatalyst. The Fe3O4@TiO2 magnetic nanoparticles (MNPs) were prepared using beet juice extract and functionalized with IL based on DABCO. Moreover, the core-shell structured magnetic Fe3O4@TiO2-IL has been characterized by different techniques such as 1H-NMR, FT-IR, VSM, XRD, SEM, TGA, TEM and EDX. To the best of our knowledge, the prepared ionic liquid displayed a good protective and activator agent for magnetic nanocatalyst. 相似文献
70.
Nonlinear Dynamics - This paper presents some dynamical and operational performance of shunt and permanent-magnet DC motors powered by lead–acid batteries for water pumping applications.... 相似文献