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991.
Chi Won Kim Jungmin Ahn Sung Min Kim Tae Hwan Noh Ok-Sang Jung 《Transition Metal Chemistry》2011,36(5):545-551
Type studies on competitive polyatomic anion versus acetonitrile coordination in the self-assembly of a series of [Ag2(X)
m
(bip)(NCCH3)
n
](X)2−m
(X− = NO3
−, CF3SO3
−, ClO4
−, BF4
−, and PF6
−; m = 0, 2; n = 0, 2, 4; bip = 1,4-bis(2-isonicotinoyloxyethyl)piperazine) were carried out. Each bip spacer acts as an N4 tetradentate ligand and is linked to four silver(I) centers through two pyridine and two piperazine moieties, producing a
double strand consisting of two 20-membered ring units. The coordinating environment around the silver(I) center is subtly
determined by the competition of the polyatomic anions with acetonitrile, that is, by the Ag···NCCH3 versus Ag···X interactions. The coordinating ability of acetonitrile is inversely proportional to the order of the coordination
ability of the Hoffmeister series of polyatomic anions, NO3
− ≫ CF3SO3
− > ClO4
− > BF4
− ≫ PF6
−. 相似文献
992.
We report on a novel method for the quantitation of proteins specifically bound on a ligand-presenting biochip by matrix-assisted laser desorption/ionization time-of-flight (MALDI-TOF) mass spectrometry (MS). The bound protein was digested by trypsin, and the resulting peptide fragments were analyzed by MALDI-TOF MS in the presence of an isotope-labeled internal standard (IS). The IS has the same sequence as a reference peptide (RP) of the target protein digest, but a different molecular weight. The absolute amount of the specifically bound protein on a biochip is then quantitated by comparison of mass intensities between the RP and the IS. Because they have the same molecular milieu, the mass intensities of these two analytes represent the real amounts of analytes on the chip. As a model system, we tested glutathione s-transferase (GST) and a GST-fusion protein, which were captured on glutathione-presenting biochips. We observed that the glutathione densities on biochips showed a good correlation with the absolute quantity of the proteins. We believe that our method will provide an alternative to currently existing tools for the absolute quantitation of surface-bound proteins. 相似文献
993.
Lipid Production by Culturing Oleaginous Yeast and Algae with Food Waste and Municipal Wastewater in an Integrated Process 总被引:2,自引:0,他引:2
Food waste and municipal wastewater are promising feedstocks for microbial lipid biofuel production, and corresponding production
process is to be developed. In this study, different oleaginous yeast strains were tested to grow in hydrolyzed food waste,
and growths of Cryptococcus curvatus, Yarrowia lipolytica, and Rhodotorula glutinis in this condition were at same level as in glucose culture as control. These strains were further tested to grow in municipal
primary wastewater. C. curvatus and R. glutinis had higher production than Y. lipolytica in media made from primary wastewater, both with and without glucose supplemented. Finally, a process was tested to grow
C. curvatus and R. glutinis in media made from food waste and municipal wastewater, and the effluents from these processes were further treated with
yeast culture and phototrophic algae culture; 1.1 g/L C. curvatus and 1.5 g/L R. glutinis biomass were further produced in second-step yeast cultures, as well as 1.53 and 0.58 g/L Chlorella sorokiniana biomass in phototrophic cultures. The residual nitrogen concentrations in final effluents were 33 mg/L and 34 mg/L, respectively,
and the residual phosphorus concentrations were 1.5 and 0.6 mg/L, respectively. The lipid contents in the produced biomass
were from 18.7% to 28.6%. 相似文献
994.
Genipin, a natural cross-linking agent, was used for the immobilization of lipase from Candida sp. 99-125 by cross-linking to two kinds of mesoporous resins. Under optimum conditions, the activity recovery of immobilized
lipase on resin NKA-9 could reach up to 96.99% when the genipin concentration was 0.5%, and it could reach up to 86.18% for
S-8 with a genipin concentration of 0.25%. Compared with using glutaraldehyde as a cross-linking agent, the immobilized lipase
using genipin showed better pH and thermal stability, storage stability, and reusability. The residual activity of immobilized
lipase using genipin as cross-linker remained more than 60% of its initial activity after six hydrolytic cycles, whereas only
about 35% activity remained by using glutaraldehyde as cross-linker. 相似文献
995.
A new nucleophilic 1,3-rearrangement is observed when treating 2-methoxyquinolino-3-lithium with an α-C substituted deoxybenzoin,and this rearrangement yielded an unusual 3,4-disubstituted 3,4-dihydroquinoline.Several similar reactions were designed and executed to investigate this novel 1,3-rearrangement,and a mechanism involving a nucleophilic addition and a following 1,3-rearrangement with an unusual dearomatization on the quinoline ring is proposed. 相似文献
996.
Guang-Qi Jiang Ruo Wang Li-Li Long Tao Sun Zai-chang Yang Yun-Qian Zhang 《Journal of Coordination Chemistry》2016,69(4):678-686
Four new complexes have been prepared and characterized from reaction of the tetrapodal Schiff base ligand 1,1,1,1-tetrakis[(3-methoxysalicylaldimino)methyl]methane (H4L) with Cu(II), Ni(II) and Cd(II). X-ray diffraction experiments revealed that 1 ([Cu2L·2H2O]·H2O) and 2 ([Cu2L·2CH3OH]·3H2O) are dinuclear complexes, with the same tetragonal pyramidal coordination geometries around their Cu(II) ions. Complex 3 ([Ni2L]·2H2O) is dinuclear with two square planar Ni(II) ions coordinated to two pairs of the pendant branches of H4L. Complex 4 ([Cd3(HL)2]·3H2O) is a linear trinuclear species with three Cd(II) ions, which were intermolecularly coordinated to three pendant branches of two H4L ligands via an uncommon intermolecular phenoxo oxygen face-sharing mode. The in vitro antimicrobial activities of H4L and its complexes were evaluated against four micro-organisms (Colibacillus, Staphylococcus aureus, Pseudomonas aeruginosa, and Bacillus subtilis) using the tube-dilution method. The results revealed that 3 showed good inhibitory activity against the Gram-positive bacteria S. aureus and B. subtilis with MIC values of 62.5 and 31.0 μg mL, respectively. 相似文献
997.
Yin-Di Zhu Jing-Yi Zhang Peng-Fei Li Hai-Feng Wu Nai-Liang Zhu Hai Jiang 《Natural product research》2016,30(9):1075-1080
Two new abietane diterpenoid glycosides, named clinopoditerpenes B (1) and C (2), were isolated from Clinopodium chinese. The structures of the new compounds were determined on the basis of extensive spectral analysis. Compound 1 exhibited cardioprotective effect against H2O2-induced apoptosis in H9c2 cells. 相似文献
998.
A series of compounds possessing 2-(3-phenyl)ureidothiazol-4-formamide derivatives with a 2-ureidothiazole scaffold were designed and synthesized. Some compounds demonstrated inhibition of cell proliferation against both MDA-MB-231 and HepG2 cell lines using Sorafenib as the positive control. Compounds 6i showed a good to moderate inhibition on VEGFR-2 and PI3Kα which was proved by further molecular docking study. This study suggests that compound 6i is a potential dual inhibitor of VEGFR-2 and PI3Kα and is applicable for further investigation. 相似文献
999.
Yan-Peng Gao Le Guo Yan-Hua Lv Wei Dong Min Jia 《Journal of Coordination Chemistry》2016,69(24):3745-3761
We have synthesized a series of metal–organic coordination frameworks under solvothermal conditions, formulated as [Cu(L)(phen)](1), [Co2(L)2(bib)]·CH3OH(2), [Co(L)(btmb)0.5](3), [Zn(L)(bib)]·2H2O(4), [Cu(L)(bib)]·DMF(5), and [Mn4(L)4(bimb)(CH3OH)](6) based on a flexible multicarboxylic bridging ligand 4,4′-methylenebis(oxy)-dibenzoic acid (H2L) and flexible N-donor ligands 1,4-bis (1H-imidazol-1-yl)-butane (bib), 1,4-bis(1H-1,2,4-triazol- 1-ylmethyl)benzene (btmb), and 1,4-bis(1H-imidazol-1-ylmethyl)benzene (bimb). The structures of the frameworks have been determined by single-crystal X-ray diffraction analyses and further characterized by elemental analyses, IR spectra, and thermogravimetric analyses. The crystal structure determinations reveal that 1 has a 1-D Z-shape chain. Compounds 2 and 3 are 2-D twofold parallel interpenetrating 4-connected net with the Schläfli symbol {44·62}. Compound 4 is a 2-D threefold parallel interpenetrating 4-connected nets with the Schläfli symbol {44·62}. Compound 5 is 3-D 4-connected net with the Schläfli symbol {65·8}. Compound 6 is characterized by a three-dimensional framework with one-dimensional homogeneous Mn-carboxylate chain. We found that flexible carboxylate ligands have different coordination modes under different synthetic conditions. The flexible skeleton of ligands and the coordination angle between the ligand and the metal ion is described. The luminescence and thermogravimetric properties of these compounds have been investigated. 相似文献
1000.
Two new nimbolinin‐type limonoids, 12‐ethoxynimbolinins E and F ( 1 and 2 , resp.), together with seven known analogues, 1α‐benzoyloxy‐3α‐acetoxyl‐7α‐hydroxy‐12β‐ethoxynimbolinin ( 3 ), nimbolinin B ( 4 ), meliatoosenin L ( 5 ), 14,15‐deoxy‐11‐oxohavanensin 3,12‐diacetate ( 6 ), 12α‐hydroxymeliatoosenin ( 7 ), toosendansin A ( 8 ), and toosendansin C ( 9 ), were isolated from the fruits of Melia toosendan. The structures of these compounds were elucidated by spectroscopic analysis. All the compounds were evaluated for their cytotoxicity against five tumor cell lines. 相似文献