نتایج جستجو برای: oxygen bridged dihydropyrimidinone
تعداد نتایج: 215526 فیلتر نتایج به سال:
Abstract The enaminone, (2 E )-3-(dimethylamino)-1-(3,4,5-trimethoxyphenyl) prop-2-en-1-one was prepared by refluxing 3,4,5-trimethoxy acetophenone with dimethylformamide dimethylacetal (DMF–DMA) without solvent for 12 h. dihydropyrimidinone derivatives (1–9) were reacting substituted benzaldehydes and urea in glacial acetic acid. compounds synthesized significant yield using one step multicomp...
a condensation of various isatins with indole derivatives has been carried out in the presence of 1,3-dibromo-5,5-dimethylhydantoin (dbdmh) as catalyst at 50 °c in ethanol in order to form 3,3-bis(indolyl) oxindoles. the products were obtained within 20-90 min by 70-96% yields. the efficacy of the procedure has been confirmed by catalyzing the condensation reaction of pyrrole which was used as ...
the synthesis, spectroscopic and magnetic characterization of a series of new alkoxo-bridged binuclear copper (ii) compounds are described. all complexes have the general formula [cu (m-or)(l)2]2(clo4)2 · x h2o, in which m-or = ch3o-, c2h5o- or c3h7o-, l = 2-amino-4-methylpyridine (abbreviated a4pic) and 2-amino-5-methylpyridine ( abbreviated a5pic). the title compounds all consist of dinuclear...
In this contribution we describe a set of three chlorinated bridged ethers with varying number sulphur and oxygen atoms. The substitution leads to highly emissive compounds tunable photophysical properties in relationship their state aggregation, i.e., solution, as aggregates the solid state. Additionally, an in-depth X-ray diffractometric analysis supported by Hirshfeld study non-covalent inte...
We report a metal–organic framework (MOF) with rare two-dimensional (2D) secondary building unit (SBU). The SBU comprises mixed-valent Fe2+ and Fe3+ metal ions bridged by oxygen atoms pertaining to the polytopic ligand 3,3′,4,4′,5,5′-hexahydroxybiphenyl, which also define iron-oxide 2D layers. Overall, anionic exhibits topology evidences strong electronic communication between mixed-valence iro...
The decomposition of N2O on dinuclear oxygen-bridged iron sites in Fe-ZSM-5 was simulated under steady-state conditions considering the reaction mechanism and the rate parameters proposed by Hansen et al. [J. Phys. Chem. C 111 (2007) 2092] on the basis of DFT calculations. The presence of low concentrations of water vapor in the feed stream (ppb to ppm levels) affects the calculated values for ...
We have investigated the reaction products of several iron(III) compounds with hydrogen peroxide, and have found that hydrogen peroxide promotes the formation of an oxo-bridged iron(III) species in the presence of methanol (electron donor), and carboxyl groups of the ligand systems play a role to give the tetranuclear iron(III) compound containing a bent Fe-O-Fe unit (O: oxo oxygen atom). Based...
objective: to assess the effect of combination of pulsed electromagnetic fields (pemf) with predatory stress on transected sciatic nerve regeneration in rats. methods: in sham- operated group (sog) the nerve was manipulated and left intact. the 10-mm rat sciatic nerve gap was created in rats. in transected group (transected) nerve stumps were sutured to adjacent muscle and in vein graft group ...
نمودار تعداد نتایج جستجو در هر سال
با کلیک روی نمودار نتایج را به سال انتشار فیلتر کنید