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Ternary solid complex was synthesized via hybridization of curcumin(Cur), hydroxyapatite(HAP), lanthanum(La) and acetic acid(HAc). The nano-scale hybrid composite of La-Cur/HAP was directly prepared by the wet method. The morphologies and structures of the composite were characterized by scanning electron microscopy (SEM), infrared(IR) spectroscopy, X-ray diffraction(XRD), transmission electron microscopy(TEM) and energy dispersive X-ray spectroscopy. The antibacterial activities were tested by methods of minimum inhibitory concentration (MIC) and minimum bactericidal concentration(MBC). The results show that the size of the La-Cur/HAP composite is less than 100 nm, and the composite exhibits strong bacteriostatic activity against Escherichia coli(E, colt) and Staphylococcus aureus(S, aureus) at low concentrations(in the range of 26-92μg/mL). The composite can exhibit both of the bacteria and shows higher antibacterial activity against S. aureus than against E. colt. At the same time, La-Cur/HAP shows stronger antibacterial efficiency than ampicillin/HAP. 相似文献
54.
We reported the environmental benign synthesis of chalcones,2-pyrazolines and cyclohexanones under microwave irradiation.Chalcones were obtained by the condensation of each of 2-hydroxyacetophenone derivatives with a-naphthaldehyde under microwave irradiation.The condensation reactions of each of synthesized chalcones with phenyl hydrazine under microwave irradiation in the presence of dry acetic acid as a cyclizing agent gave 2-pyrazolines.Also,the new cyclohexenone derivatives,valuable intermediates to synthesize fused heterocycles,have been prepared by the cyclocondensation of each of hydroxychalcones with ethyl acetoacetate.The structures of the synthesized compounds were elucidated by infrared(IR) spectrometry,nuclear magnetic resonance(NMR),mass spectrometry(MS) and elmental analysis.The results indicate that unlike classical heating,microwave irradiation results in higher yields with shorter and cleaner reactions.The synthesized compounds were screened for antimicrobial activity against Staphylococcus aureus,Escherichia coli,Candida Albicans and Aspergillus niger.We clarified the effects of different substituents in the tested compounds on the obtaind antibacterial activities and antifungal activities. 相似文献
55.
YANG Gao-Shan LIU Chong-Bo LI Heng-Nong CHEN Yuan HUANG De-He WEN Hui-Liang 《结构化学》2014,33(4):528-534
Two heterocyclic Schiff bases were synthesized via the condensation reactions of primary amines with carbonyl compounds. 2-[(4-pyridylmethylene)-amino] phenol(compound 1) was synthesized by the interaction of 4-pyridinecarboxaldehyde with o-aminophenol in ethanol solvent; N,N‘-bis(3-(furan-2-yl)allylidene)benzene-1,4-diamin(compound 2) was synthesized by the interaction of 3-(2-furyl)acrolein with p-phenylenediamine in ethanol medium. The compounds were characterized by elemental analysis, IR, MS and single-crystal X-ray diffraction. Compound 1(C12H10N2O) crystallizes in the monoclinic system, space group P21/c with a = 7.0771(7), b = 7.2820(7), c = 19.849(2),β= 96.3390(10)°, V = 1016.66(17) ?3, Z = 4, Mr = 198.22, Dc = 1.295 g/cm3, F(000) = 416, GOOF = 1.060, μ= 0.085 mm-1, the final R = 0.0371 and wR = 0.0929 for 1497 observed reflections with I 2σ(I). Compound 2(C20H16N2O2) crystallizes in the orthorhombic system, space group Fdd2 with a = 26.344(15), b = 48.50(3), c = 5.293(3), V = 6764(7) ?3, Z = 16, Mr = 316.35, Dc = 1.243 g/cm3, F(000) = 2656, GOOF = 1.043, = 0.081 mm-1, the final R = 0.0526 and wR = 0.1267 for 2059 observed reflections with I 2σ(I). 1 and 2 molecules are connected through hydrogen bonds to generate a 2D network and a 1D chain structure, respectively. The preliminary antibacterial activity results showed that the title compounds display excellent antibacterial activities to Escherichia coli, Staphylococcus aureus and Bacillus subtilis. 相似文献
56.
A novel spiro-compound(C20 H15 N2 O3 P) has been synthesized and characterized by means of IR and 1H NMR. Its crystal structure was determined by X-ray diffractometry. The crystal belongs to the monoclinic system, space group P21 /c with a = 9.1628(7), b = 12.9490(7), c = 15.7898(11), β = 103.952(8)o, Mr = 36.08, V = 1818.2(2)3, Z = 4, Dc = 1.382 g/cm3, F(000) = 788, μ = 0.179 mm-1, R = 0.0701 and wR = 0.1513. The preliminary biological test showed that the title compound has activities against Escherichia coli, S.albus, Bacillus subtilis, Staphylocc- ocusaureus and Micrococcus tetragenus with MIC to be 0.038, 0.038, 0.075, 2.48, and 0.15 mg/mL, respectively. 相似文献
57.
A new 2D barium-organic framework, [Ba2(Hbidc)2]n(1, Hbidc = 1H-benzimidazole-5,6-dicarboxylate), has been solvothermally synthesized and structurally characterized by elemental analysis, IR spectroscopy, TGA, powder X-ray diffraction, and single-crystal X-ray diffraction. The crystal belongs to the triclinic system, space group P1 with a = 6.8785(14), b = 9.4558(19), c = 14.641(3) , α = 86.22(3), β = 82.27(3), γ = 88.40(3)°, V = 941.4(3) 3, Z = 2, Mr = 682.96, Dc = 2.409 g/cm3, μ(MoKα) = 4.217 mm-1, F(000) = 640, the final R = 0.0587 and wR = 0.1619 for 3030 observed reflections with I 2σ(I). Structural determination reveals that 1 exhibits an interesting 2D layer structure constructed by carboxylate groups of Hbidc ligands and shows good thermal stability(up to 400 ℃). Solid-state 1 emits intense indigotin photoluminescence with fluorescence lifetime of 62.13(408 nm) at room temperature. The H3bidc ligand and its barium complex have been screened for antibacterial activity against several bacteria strains, and the results are compared with the activity of penicillin. 相似文献
58.
Monomer of 7-methacryloyloxy-4-methylcoumarin(MAOMC) was synthesized and characterized by FTIR, 1H-NMR and 13C-NMR spectroscopy. Copolymers of MAOMC with butoxyethylmethacrylate(BOEMA) at different feed compositions were prepared by free radical solution polymerization at(70 ± 1) °C in ethylmethylketone(EMK) using benzyl peroxide(BPO) as an initiator. The copolymers were characterized by FTIR and 1H-NMR spectroscopy. Thermogravimetric analysis(TGA) and differential scanning calorimetry(DSC) of the copolymers showed moderate thermal stability and higher Tg values. Gel permeation chromatography(GPC) was used to find out the molecular weights of the different copolymers. Antibacterial activities of the copolymers were also investigated against the selected pathogenic bacteria's. The antibacterial activity of the copolymer increases as the MAOMC content increases in the copolymer. This shows that coumarin moiety plays a very important role in the antibacterial activity. 相似文献
59.
在乙醇胺-水混合溶液中采用水热处理硫酸铜的方法制备了多结构的铜树枝晶;采用X射线粉末衍射仪、扫描电子显微镜、透射电子显微镜分析了所得样品的结构和形貌;采用牛津杯法评价了其对金黄葡萄球菌、枯草芽孢杆菌、大肠杆菌和绿脓杆菌的抗菌性能.结果表明,铜树枝晶由一个长的一级中心主干和许多高度对称分布在主干两侧的二级分支结构构成,且形貌均匀;反应温度、反应时间以及溶剂组成对铜树枝晶的形貌有很大影响.与此同时,铜树枝晶表现出选择性的抗菌行为,对金黄葡萄球菌、枯草芽孢杆菌和绿脓杆菌更有效. 相似文献
60.
由于抗生素的不当使用和细菌多药耐药的出现, 迫切需要开发新的抗菌剂. 本文制备了具有光热转换性能的正电荷半导体高分子材料及具有协同抗菌活性的半导体聚合物纳米粒子(SP-PPh3 NPs). SP-PPh3 NPs的光热转化效率为43.8%. 带正电荷的SP-PPh3 NPs可以附着在细菌上, 有助于将热量有效传递给细菌. 在热和正电荷的协同作用下, SP-PPh3 NPs对革兰氏阴性大肠杆菌(E. coli)和革兰氏阳性金黄色葡萄球菌(S. aureus)均具有抗菌活性, 其对二者的体外抑菌率分别为99.9%和98.6%. 此外, SP-PPh3 NPs具有良好的生物相容性, 对小鼠的主要器官几乎无副作用. 对细菌感染的小鼠皮肤伤口用SP-PPh3 NPs治疗12 d后, 伤口可以很好地愈合. 相似文献