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51.
Ch. Raji Reddy N. Kiranmai G. Dattatreya Sarma S. Chandrasekhar 《Tetrahedron letters》2007,48(2):215-218
The first use of hydroxylamine derivatives as the aminoxy equivalent of nucleophiles in palladium catalyzed addition to Baylis-Hillman acetate adducts is described. The reaction proceeds smoothly to give the substituted allyloxy amines in good yield and selectivity. 相似文献
52.
Raman Natarajan Kulandaisamy Antonysamy Thangaraja Chinnathangavel Jeyasubramanian Kadarkaraithangam 《Transition Metal Chemistry》2003,28(1):29-36
Neutral tetradentate chelate complexes of CuII, NiII, CoII, MnII, ZnII and VOII have been prepared in EtOH using Schiff bases derived from acetoacetanilido-4-aminoantipyrine and 2-aminophenol/2-aminothiophenol. Microanalytical data, magnetic susceptibility, i.r., u.v.–vis., 1H-n.m.r. and e.s.r. spectral techniques were used to confirm the structures of the chelates. Electronic absorption and i.r. spectra of the complexes suggest a square-planar geometry around the central metal ion, except for VOII and MnII complexes which have square-pyramidal and octahedral geometry respectively. The cyclic voltammetric data for the CuII complexes in MeCN show two waves for copper(II) copper(III) and copper(II) copper(I) couples, whereas the VOII complexes in MeCN show two waves for vanadium(IV) vanadium(V) and vanadium(IV) vanadium(III) couples. The e.s.r. spectra of the CuII, VOII and MnII complexes were recorded in DMSO solution and their salient features reported. The in vitro antimicrobial activity of the investigated compounds was tested against the microorganisms such as Salmonella typhi, Staphylococcus aureus, Klebsiella pneumoniae, Bacillus subtilis, Shigella flexneri, Pseudomonas aeruginosa, Aspergillus niger and Rhizoctonia bataicola. Most of the metal chelates have higher antimicrobial activity than the free ligands. 相似文献
53.
K. Anitha S. Athimoolam S. Natarajan 《Acta Crystallographica. Section C, Structural Chemistry》2006,62(9):o567-o570
In the structure of l ‐prolinium picrate, C5H10NO2+·C6H2N3O7−, the Cγ atom of the pyrrolidine ring has conformational disorder. Both the major and minor conformers of the pyrrolidine ring adopt conformations intermediate between a half‐chair and an envelope. Both the cation and anion are packed through chelated three‐centred N—H⋯O hydrogen bonds. The prolinium cation connects two different picrate anions, leading to an infinite chain running along the b axis. In 2‐methylpyridinium picrate, C6H8N+·C6H2N3O7−, the cations and anions are packed separately along the a axis and are interconnected by N—H⋯O hydrogen bonds. Intramolecular contacts between phenolate O atoms and adjacent nitro groups are identified in both structures. A graph‐set motif of R12(6) is observed in both structures. 相似文献
54.
The crystal structure of [C10N2H10]2[P2Mo5O21(OH)2] · 2H2O, contains the heteropolyanion, [P2Mo5O21(OH)2]4—, together with diprotonated 4, 4′‐bipyridine. The heteropolyanion is built up from five MoO6 octahedra sharing four common edges and one common corner, capped by two PO3(OH) tetrahedra. The structure is stabilized by hydrogen bonds involving the hydrogen atoms of the 4, 4′‐bipyridine, water molecules and the oxygen atoms of the pentamolybdatobisphosphate. This is the first example that this kind of cluster could be isolated in the presence of a poly‐functional aromatic molecule ion. Crystal data: triclinic, P1¯ (No. 2), a = 9.983(2)Å, b = 11.269(2)Å, c = 17.604(4)Å, α = 73.50(3)°, β = 84.07(3)°, γ = 67.96(3)°; V = 1760.0(6)Å3; Z = 2; R1 = 0.037 and wR2 = 0.081, for 9138 reflections [I > 2σ(I)]. 相似文献
55.
Using a quasi-optical continuously tunable spectrometer in the frequency range of 40–90 GHz (=7.5-3.3 mm) the absorption spectra of the superionic conductors Na-alumina, Ag-alumina,-AgI and CuTeBr have been measured at various temperatures. In the measured spectral range all the materials showed a monotonic increase in the absorption as a function of frequency. These results are discussed in the light of existing theoretical models.Alfred P. Sloan Foundation Fellow 相似文献
56.
Vanadate garnet systems namely Ca2NaMg2V3O12, individually doped with Dy and Sm and also co-doped with both the RE ions were synthesized via the solid-state reaction route and their photoluminescence (PL) properties were investigated. The method of synthesis was verified by the formation of single phase compound through X-ray diffraction (XRD) studies. Existence of energy transfer in between the host and the dopant ions was established by PL investigation. Color coordinates of all the compounds were calculated and plotted on the CIE diagram. It was seen that the co-doped system has a near white light emission. It was concluded that this single phosphor is capable of converting the ultraviolet emission of a UV-LED into white light. 相似文献
57.
Synthesis,characterization and biological screening studies of mixed ligand complexes using flavonoids as precursors
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Flavonoids are a group of plant phenolics that provide various health benefits through cell signalling pathways and antioxidant effects. In the present study, a new series of mixed ligand complexes of Co(II), Ni(II), Cu(II) and Zn(II) were synthesized by incorporating curcumin and quercetin flavonoid precursors. The structural features of the synthesized complexes were explored using elemental analysis, thermogravimetric analysis, UV–visible, infrared, NMR, mass and electron paramagnetic resonance spectral analyses and conductivity measurements. These data support an octahedral geometry of the synthesized complexes. In silico biological activity score for the ligand was predicted using PASS online software. ADMET properties were studied using VLS3D online software. Anti‐inflammatory and antioxidant activities were experimentally validated which prove that theoretical predictions are in agreement with the experimental results. Interestingly the synthesized complexes interact with calf thymus DNA through groove binding mode. Moreover, they have good potential to cleave pUC19 DNA. Minimum inhibitory concentration values of the synthesized complexes reveal that they have better antimicrobial efficacy than the ligands. 相似文献
58.
The term “liquid crystal” signifies a state of aggregation that is intermediate between the crystalline solid and the isotropic liquid. A substance in this state is strongly anisotropic in some of its properties and yet exhibits a certain degree of fluidity, which in some cases may be comparable to that of an ordinary liquid. A large number of organic compounds are now known to form liquid crystals. An essential requirement for mesomorphism to occur is that the molecules must be highly geometrically anisotropic. The transition to the intermediate state may be brought about by purely thermal processes (thermotropic mesomorphism) o r by the action of solvents (lyotropic mesomorphism). 相似文献
59.
First and practical method for preparing a solid supported 1,3-diol is described starting from commercially available Merrifield's Resin. 相似文献
60.
Biological contour,molecular docking and antiproliferative studies of DNA targeted histidine based transition metal(II) complexes: Invention and its depiction
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A novel series of histidine derived transition metal complexes were synthesized and characterized by multispectral techniques such as UV‐Vis., FT IR, EPR, NMR, ESI‐mass analysis and other physico‐chemical methods like elemental analysis, molar conductivity, magnetic susceptibility. The synthesized compounds were attempted for their biological prospective. The biological studies involved are DNA interaction (binding and damage), antimicrobial, antioxidant, antiproliferative and molecular docking. DNA interaction studies were carried out with the help of UV‐Vis absorption titration, viscosity measurement and cyclic voltammetric techniques which revealed that the synthesized compounds could interact with CT‐DNA through intercalative binding mode. A gel electrophoresis assay demonstrated the ability of complexes to cleave the supercoiled pUC18 DNA. The antioxidant property shows that the metal complexes have preferable ability to scavenge hydroxyl radical than the ligand. Moreover, the antimicrobial assay indicates that these complexes are good antimicrobial agents against various pathogens. Furthermore, the in vitro antiproliferative activities of the complexes were examined on HeLa, Hep G2 and NIH 3 T3 cell lines using an MTT assay. The morphological changes were investigated using Hoechst 33258 staining apoptosis assay. In addition, molecular docking studies were executed to considerate the nature of binding of the synthesized complexes with protein and DNA. 相似文献