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341.
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343.
Masahiko Maekawa Toshie Minematsu Hisashi Konaka Megumu Munakata 《Inorganica chimica acta》2006,359(1):168-182
Four novel mononuclear Rh-Cp* and Ir-Cp* complexes with polycyclic aromatic hydrocarbons (PAHs), [M(Cp*)(η6-PAHs)](BF4)2 (M = Rh and Ir; Cp* = η5-C5Me5; PAHs = phenanthrene (phn), pyrene (pyr) and triphenylene (triph)), were prepared by the reactions of the intermediate [M(Cp*)(Me2CO)3]2+ with appreciable PAHs. Their structures were characterized by a single crystal X-ray analysis, 1H, 13C {1H} NMR and 2D NMR techniques. The X-ray crystallographic studies showed that the [M(Cp*)]2+ fragment is η6-coordinated to one terminal benzene ring in each PAH. In particular, it is interesting to note that the partial π/π/π/π interaction was formed in the Ir-pyr complex [Ir(Cp*)(η6-pyr)](BF4)2. The 1D and 2D NMR studies described that the Rh-Cp* and Ir-Cp* complexes with PAHs gave unique 1H and 13C {1H} NMR spectra with positive coordination shifts (Δδ(1H, 13C)) in (CD3)2CO at 23 °C, which are likely induced by the local effect and the non-local effect on the coordination of the [M(Cp*)]2+ fragment to PAHs. The decreasing of the coupling constants (3JH-H) in the η6-coordinated benzene ring is also induced, with no changes in the uncoordinated benzene rings. The time-course of 1H NMR spectra showed that Rh-Cp* and Ir-Cp* complexes with PAHs are partially dissociated to [M(Cp*)(Me2CO)3]2+ and metal-free PAHs in (CD3)2CO at 23 °C. It was demonstrated that their stabilities are in the order of Ir-triph, Ir-phn, Ir-pyr and Rh-triph complexes in (CD3)2CO. 相似文献
344.
S Arai M Furukawa T Munakata K Kuwano H Inoue T Miyazaki 《Microbiology and immunology》1990,34(3):231-243
Tumor necrosis factor-alpha (TNF-alpha)-inducing activity of several mycoplasmas including Mycoplasma pneumoniae, a causative agent in human respiratory infectious diseases, was investigated. Purified peritoneal macrophages from BALB/c mice markedly enhanced their cytotoxic activity to Meth A cells, when cultured with either viable or non-viable mycoplasmas. The supernatants of the macrophage culture with mycoplasmas, M. pneumoniae and Acholeplasma laidlawii, showed the potent cytotoxic activity to TNF-alpha-sensitive L cells but not to TNF-alpha-insensitive L cells. Addition of anti-TNF-alpha antiserum inhibited completely the cytotoxic activity of these supernatants, indicating that a major part of the cytotoxic activity might be due to TNF-alpha. Various other mycoplasmas, either glucose- or arginine-utilizing species, as far as tested showed also the potent activity to produce TNF-alpha. These results strongly suggest the possibility that mycoplasmas possess the activity of TNF-alpha induction which might be responsible for a part of enhancement of cytotoxic activity of macrophages and resistance to infection with mycoplasmas in vivo. 相似文献