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Prepared Compounds (prepared + compound)
Selected AbstractsFacile Synthesis of Flexible Bis(pyrazol-1-yl)alkane and Related Ligands in a Superbasic MediumEUROPEAN JOURNAL OF ORGANIC CHEMISTRY, Issue 30 2007Andrei S. Potapov Abstract Flexible ligands 1,3-bis(pyrazol-1-yl)propanes, bis[2-(pyrazol-1-yl)ethyl] ethers, and bis[2-(3,5-dimethylpyrazol-1-yl)ethyl]amine were prepared by a facile procedure involving the reaction of pyrazoles with 1,3-dibromopropane, bis(2-chloroethyl) ether or bis(2-chloroethyl)amine hydrochloride in a superbasic medium (dimethyl sulfoxide/potassium hydroxide). Reaction of bis(2-chloroethyl)amine and pyrazole unexpectedly led to 1,4-bis[2-(pyrazol-1-yl)ethyl]piperazine. The corresponding 4,4,-diiodo-substituted bis(pyrazole) derivatives were prepared by oxidative iodination with I2/HIO3/H2SO4 in acetic acid. Vilsmeier,Haak formylation of some of the prepared compounds yielded the corresponding dialdehydes.(© Wiley-VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2007) [source] Synthesis of ethyl 6-aryl-4-oxo-4,6-dihydro-1(12)(13)h -pyrimido-[2,,1,:4,5][1,3,5]triazino[1,2- a]benzimidazole-3-carboxylates,JOURNAL OF HETEROCYCLIC CHEMISTRY, Issue 6 2006Anton V. Dolzhenko The synthesis of ethyl 6-aryl-4-oxo-4,6-dihdro-1(12)(13)H -pyrimido[2,,1,:4,5][1,3,5]triazino[1,2- a]-benzimidazole-3-carboxylates (4a-p) was described via pyrimidine ring annulation to 4-aryl-3,4-dihydro[1,3,5]triazino[1,2- a]benzimidazole-2-amines (2a-p) which were obtained from 2-guanidinobenzimidazole (1). Tautomerism in the prepared compounds was investigated using nmr spectroscopy. Compounds 2a-p were found to be present in dimethyl sulfoxide solution predominantly as 3,4-dihyhydro tautomeric form. Compounds 4a-p existed in dynamic equilibrium of 1-, 12- and 13H -forms. It was found that methylation of 4a-d led to 13-methyl substituted derivatives 9a-d exclusively. [source] Preparation of 2-phenyl-2-hydroxymethyl-4-oxo-1,2,3,4-tetrahydroquinazoline and 2-methyl-4-oxo-3,4-dihydroquinazoline derivatives formation,JOURNAL OF HETEROCYCLIC CHEMISTRY, Issue 4 2000Pavel Hradil The cyclization of phenacyl anthranilate has been studied with the aim to develop the synthesis of 2-(2,-aminophenyl)-4-phenyloxazole. However, a different course of the reaction than expected was observed. 2-Phenyl-2-hydroxymethyl-4-oxo-1,2,3,4-tetrahydroquinazoline (3a) was formed by the reaction of phenacyl anthranilate (2) with ammonium acetate under various conditions. 3-Hydroxy-2-phenyl-4(1H)-quinolinone (4) arose by heating compound 3a in acetic acid. The same compound was obtained by melting compound 3a, but the yield was lower. Different types of products resulted in the reaction of compound 3a with acetic anhydride. Under mild conditions acetylated products 2-acetoxymethyl-2-phenyl-4-oxo-1,2,3,4-tetrahydroquinazoline (7a) and 2-acetoxymethyl-3-acetyl-2-phenyl-4-oxo-1,2,3,4-tetrahydroquinazoline (8) were prepared. If the reaction was carried out under reflux of the reaction mixture, molecular rearrangement took place to give cis and trans 2-methyl-4-oxo-3-(1-phenyl-2-acetoxy)vinyl-3,4-dihydroquinazolines (9a and 9b). All prepared compounds have been characterised by their 1H, 13C and 15N NMR spectra, IR spectra and MS. [source] Low-Loss Microwave Dielectrics Using Mg2(Ti1,xSnx)O4 (x=0.01,0.09) Solid SolutionJOURNAL OF THE AMERICAN CERAMIC SOCIETY, Issue 10 2009Cheng-Liang Huang Low-loss ceramics having the chemical formula Mg2(Ti1,xSnx)O4 for x ranging from 0.01 to 0.09 have been prepared by the conventional mixed oxide route and their microwave dielectric properties have been investigated. X-ray powder diffraction patterns indicate the corundum-structured solid solutions for the prepared compounds. In addition, lattice parameters, which linearly increase from 8.4414 to 8.4441 Å with the rise of x from 0.01 to 0.09, also confirm the forming of solid solutions. By increasing x from 0.01 to 0.05, the Q×f of the specimen can be tremendously boosted from 173 000 GHz to a maximum 318 000 GHz. A fine combination of microwave dielectric properties (,r,15.57, Q×f,318 000 GHz at 10.8 GHz, ,f,,45.1 ppm/°C) was achieved for Mg2(Ti0.95Sn0.05)O4 ceramics sintered at 1390°C for 4 h. Ilmenite-structured Mg(Ti0.95Sn0.05)O3 (,r,16.67, Q×f,275 000 GHz at 10.3 GHz, ,f,,53.2 ppm/°C) was detected as a second phase. The presence of the second phase, however, would cause no significant variation in the dielectric properties of the specimen, because the second phase properties are very similar to the primary phase. These unique properties, in particular, low ,r and high Q×f, can be utilized as a very promising dielectric material for ultra-high-frequency applications. [source] Synthesis and antimicrobial activities of sulfonohydrazide-substituted 8-hydroxyquinoline derivative and its oxinatesAPPLIED ORGANOMETALLIC CHEMISTRY, Issue 5 2010Ritu B. Dixit Abstract Looking at the pharmacological importance of 8-hydroxyquinolines and sulfonamides, in the present study, a novel bi-dentate ligand 4-amino- N,-[(8-hydroxyquinoline-5-yl)methyl] benzenesulfonohydrazide (AHQMBSH) having above both moieties within a single molecular framework was synthesized by the reaction of N -acetamidobenzene sulfonohydrazide with 5-chloromethyl-8-hydroxyquinoline hydrochloride. Its metal(II) oxinates were also prepared with Mn(II), Fe(II), Co(II), Ni(II), Cu(II) and Zn(II) salts. All the above compounds were investigated by physicochemical analyses, thermogravimetric analysis and spectroscopic techniques. Antimicrobial activities for the above prepared compounds were carried out using the agar-plate method against various strains of bacteria (Staphylococcus aureus, Bacillus subtillis, Pseudomonas aerugionsa, Escherichia coli) and fungi (Aspergillus niger and Aspergillus flavous). The results show a significant increase in antimicrobial and antifungal activities of AHQMBSH compared with the parent 8-hydroxyquinoline and sulfonamides. Copyright © 2010 John Wiley & Sons, Ltd. [source] Synthesis of New Quinoline Derivatives as Inhibitors of Human Tumor Cells GrowthARCHIV DER PHARMAZIE, Issue 8 2010Aymn E. Rashad Abstract A series of new 8-[(2H -tetrazol-5-yl)methoxy]quinoline derivatives, their sugar hydrazones, and their N -glycoside derivatives were synthesized. Furthermore, the 1,2,4-triazole-3-one derivatives 3 and 4 were synthesized from the amidrazone derivative 2. Some of the newly prepared compounds demonstrated inhibitory effects on the growth of MCF-7 human breast cancer cells as compared with the activity of the commonly used anticancer drug, cisplatin. The results of antitumor evaluation revealed that compounds 2,5, 8b, and 12 inhibited the growth of cancer cells through their effect as free-radical regulators by increasing the activity of superoxide dismutase and depletion of intracellular levels of reduced glutathione, catalase and glutathione peroxidase activities, accompanied with a high production of hydrogen peroxide, nitric oxide, and other free radicals causing the killing of tumor cells. The results suggested that the prepared compounds possess significant anticancer activity comparable to cisplatin and the antitumor activity of these prepared compounds was accompanied with a reduction in the levels of protein and nucleic acids. [source] Synthesis, Structure, and Physico-optical Properties of Manganate(II)-Based Ionic LiquidsCHEMISTRY - A EUROPEAN JOURNAL, Issue 11 2010Slawomir Pitula Dr. Abstract Several ionic liquids (ILs) based on complex manganate(II) anions with chloro, bromo, and bis(trifluoromethanesulfonyl)amido (Tf2N) ligands have been synthesized. As counterions, n- alkyl-methylimidazolium (Cnmim) cations of different chain length (alkyl=ethyl (C2), propyl (C3), butyl (C4), hexyl (C6)) were chosen. Except for the 1-hexyl-3-methylimidazolium ILs, all of the prepared compounds could be obtained in a crystalline state at room temperature. However, each of the compounds displayed a strong tendency to form a supercooled liquid. Generally, solidification via a glass transition took place below ,40,°C. Consequently, all of these compounds can be regarded as ionic liquids. Depending on the local coordination environment of Mn2+, green (tetrahedrally coordinated Mn2+) or red (octahedrally coordinated Mn2+) luminescence emission from the 4T(G) level is observed.1 The local coordination of the luminescent Mn2+ centre has been unequivocally established by UV/Vis as well as Raman and IR vibrational spectroscopies. Emission decay times measured at room temperature in the solid state (crystalline or powder) were generally a few ms, although, depending on the ligand, values of up to 25,ms were obtained. For the bromo compounds, the luminescence decay times proved to be almost independent of the physical state and the temperature. However, for the chloro- and bis(trifluoromethanesulfonyl)amido ILs, the emission decay times were found to be dependent on the temperature even in the solid state, indicating that the measured values are strongly influenced by nuclear motion and the vibration of the atoms. In the liquid state, the luminescence of tetrahedrally coordinated Mn2+ could only be observed when the tetrachloromanganate ILs were diluted with the respective halide ILs. However, for [C3mim][Mn(Tf2N)3], in which Mn2+ is in an octahedral coordination environment, a weak red emission from the pure compound was found even in the liquid state at elevated temperatures. [source] | ||||||||||