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141.
142.
Thermal reaction of [Ru3(CO)12] with PH2Mes (Mes = mesityl) in refluxing toluene afforded mesitylphosphinidene-capped ruthenium carbonyl clusters, [Ru3(CO)9(μ-H)2(μ3-PMes)] (1), [Ru3(CO)8(PH2Mes)(μ-H)2(μ3-PMes)] (2), [Ru3(CO)9(μ3-PMes)2] (3), [Ru4(CO)10(μ-CO)(μ4-PMes)2] (4), and [Ru5(CO)10H2(μ4-PMes)(μ3-PMes)2] (5). All products were fully characterized and structurally confirmed by X-ray crystal structure analysis. Complexes 2-4 were also obtained in high yields by stepwise reaction starting from 1. Fluxional behavior of carbonyl groups was observed in case of 4. Complex 5 reveals a new type of skeletal structure, bicapped-octahedron having μ3- and μ4-phosphinidene ligands at the capping positions. Similar reaction of [Os3(CO)12] with PH2Mes yielded a phosphido-bridged osmium cluster [Os3(CO)10(μ-H)(μ-PHMes)] (6) and a phosphinidene-capped cluster [Os3(CO)9(μ-H)2(μ3-PMes)] (7). 相似文献
143.
Lipid A analogues containing a glucose moiety on their non-reducing end were synthesized, and their LPS-antagonistic activities were measured. The inhibitory activities (IC50) on LPS-induced TNFα production of these six compounds, 26, 33, 44β, 52β, 59, and 61, toward human whole blood cells were 0.49, 0.65, 0.51, 0.98, 0.46, and 1.11 nM, respectively. Inhibitory doses (ID50) of compounds 26, 33, 44β, 59, and 61 on TNFα production induced by coinjection of galactosamine and LPS in C3H/HeN mice were measured. The ID50 values of these compounds were 0.45, 0.96, <0.2, 1.08, and <0.2 mg/kg, respectively. Moreover, C3H/HeN mice preinjected with compounds 26, 33, and 44β were protected from lethality induced by coinjection of galactosamine and LPS. Out of eight mice preinjected with 1 mg/kg of compounds 26, 33, and 44β, five, eight and six mice were protected, respectively. 相似文献
144.
The synthesis and characterization of tungsten and molybdenum complexes of the xanthene-based bis(silyl) ligand (xantsil) with a kappa3(Si,Si,O) coordination mode are reported, where an insertion of tBuCN into a tungsten-silicon bond leads to formation of an eta2-iminoacyl complex. 相似文献
145.
Kobayashi T Yamaguchi T Ohta H Sunatsuki Y Kojima M Re N Nonoyama M Matsumoto N 《Chemical communications (Cambridge, England)》2006,(18):1950-1952
Two heterotrinuclear complexes, [Mn(II)(Ni(II)L)2].2CH3OH (where H3L = 1,1,1-tris(N-salicylideneaminomethyl)ethane) and [Fe(III)(Ni(II)L)2]NO3.C2H5OH, consisting of three face-sharing octahedra have been prepared; although these complexes have closely related structures and have the same 1-5/2-1 spin system, they show completely different magnetic interactions between the adjacent metal ions: ferromagnetic (Ni(II)-Mn(II)) and antiferromagnetic (Ni(II)-Fe(III)). 相似文献
146.
We experimentally investigated the reciprocity of scanning near-field optical microscopy between illumination and collection modes. Near-field transmission images of single gold spheres and nanorods observed by the two modes are found to be equivalent to each other in the region from visible to near infrared. This result shows that reciprocity holds for the near-field scattering problems. We found that the conventional optical selection rule for far-field excitations does not apply not only under illumination mode but also with collection-mode arrangements. The possible origin of this observation might be the near-field probe. 相似文献
147.
A poly(N-isopropylacrylamide) (PNIPAAm) gel cross-linked with quaternized aminoalkyls was designed. A novel recyclable system based on the external solvent-responsive oil-absorption/elution transition ability of the PNIPAAm gel matrix was then developed. 相似文献
148.
A new quaternary layered oxycarbide, [Al4.39(5)Si0.61(5)]Σ5[O1.00(2)C2.00(2)]Σ3C, has been synthesized and characterized by X-ray powder diffraction, transmission electron microscopy and energy dispersive X-ray spectroscopy (EDX). The title compound was found to be hexagonal with space group P63/mmc, Z=2, and unit-cell dimensions a=0.32783(1) nm, c=2.16674(7) nm and V=0.20167(1) nm3. The atom ratios Al:Si were determined by EDX, and the initial structural model was derived by the direct methods. The final structural model showed the positional disordering of one of the three types of Al/Si sites. The maximum-entropy methods-based pattern fitting (MPF) method was used to confirm the validity of the split-atom model, in which conventional structure bias caused by assuming intensity partitioning was minimized. The reliability indices calculated from the MPF were Rwp=3.73% (S=1.20), Rp=2.94%, RB=1.04% and RF=0.81%. The crystal was an inversion twin. Each twin-related individual was isostructural with Al4SiC4 (space group P63mc, Z=2). 相似文献
149.
The free radical polymerization of N-(p-vinylbenzyl)phthalimide (VBP) “initiated” with the adduct of 2-benzoyloxy-1-phenylethyl and TEMPO (BS-TEMPO) or TEMPO-terminated polystyrene (PS-TEMPO) in N,N-dimethylformamide (DMF) at 125 °C was found to proceed in a living fashion, providing low-polydispersity PVBP and block copolymers of the type PS-b-PVBA, where TEMPO is 2,2,6,6-tetramethylpiperidinyl-1-oxy. Unlike TEMPO-mediated styrene polymerization, the polymerization rate slightly but distinctly depended on the adduct concentration, which was interpretable as a pre-stationary behavior. The hydrolysis of those polymers gave poly(p-aminomethylstyrene) (PAMS) and PS-b-PAMS, and further treatment of the block copolymer with hydrogen chloride provided an amphiphilic block copolymer. The polymeric amphiphile was used as an emulsifier in emulsion polymerization to produce a positively charged polymeric microsphere. 相似文献
150.
Akihiro Ohta Sawako Masano Mayumi Tsutsui Fusako Yamamoto Sumie Suzuki Hiromi Makita Hideo Tamamura Yasuo Akita 《Journal of heterocyclic chemistry》1981,18(3):555-558
A series of 2-hydroxypyrazine 1-oxides were prepared from the corresponding chloropyrazines by two methods, including oxidation processes in satisfactory yields. The treatment of 2,3-diphenylpyrazine 1,4-dioxide ( 6 ) led to 2,3-dichloro-5,6-diphenylpyrazine ( 7 ) and 2-chloro-5,6-diphenylpyrazine 1-oxide ( 8 ), and the latter was converted to 5,6-diphenyl-2-hydroxypyrazine 1-oxide ( 9 ) by an alkaline hydrolysis. 相似文献