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Komatsu T Hayakawa S Tsuchida E Nishide H 《Chemical communications (Cambridge, England)》2003,(1):50-51
alpha-Cyclodextrin (alpha CD)-penetrating 2-methyl-1-phenethylimidazole coordinates to the zinc(II) and iron(II) complexes of meso-tetrakis[o-(N-methyl)pyridinium] porphyrinate, giving non-covalently linked alpha CD-porphyrin ensembles; the iron(II) complex can reversibly bind and release dioxygen in aqueous DMF solution. 相似文献
55.
Sotoyama W Satoh T Sato H Matsuura A Sawatari N 《The journal of physical chemistry. A》2005,109(43):9760-9766
The absorption and emission spectra of the Pt(II) complexes containing N wedge C wedge N-coordinating tridentate ligands, platinum(II) 1,3-di(2-pyridyl)benzene chloride [Pt(dpb)Cl] and platinum(II) 3,5-di(2-pyridyl)toluene chloride [Pt(dpt)Cl], together with their corresponding free ligands, 1,3-di(2-pyridyl)benzene (dpbH) and 3,5-di(2-pyridyl)toluene (dptH), have been analyzed by density functional theory (DFT) for the ground state and time-dependent DFT (TDDFT) for the excited states. T(1)(A(1)) and S(1)(B(2)) of the complexes (in C(2)(v) symmetry) were assigned on the basis of the calculated excitation energies as well as comparison of the experimental spectroscopic properties and the calculated states' characteristics. The calculated excitation energies for T(1) and S(1) of the complexes as well as those for T(1) of the free ligands were in good agreement with their observed values within 600 cm(-1). The d-pi* characters of the excited states were evaluated from the change in electron densities between the ground and excited states by Mulliken population analysis; values of 25% for T(1) and 32% for S(1) were obtained for both complexes. The calculated values of d-pi* character were found to be consistent with the reported emission lifetimes as well as the observed emission energy shifts from the corresponding free ligands. Most spectroscopic properties of the complexes and the free ligands, which include solvatochromic shift, Stokes shifts, methyl substitution shifts, and emission spectra profiles, were well explained from the calculation results. 相似文献
56.
Kobayashi S Miyamura H Akiyama R Ishida T 《Journal of the American Chemical Society》2005,127(25):9251-9254
A novel, highly active immobilized ruthenium catalyst, which can be successfully used in oxidation of alcohols to aldehydes and ketones, has been developed. In contrast to most immobilized catalysts, the Ru catalyst has activity that is higher than that of the original non-immobilized catalyst. In a batch system, the Ru catalyst was recovered and reused several times without loss of activity. The catalyst was also applied to a flow system, in which excellent conversions and yields were demonstrated. No leaching of Ru was observed in both cases. 相似文献
57.
Hiroyoshi Kamogawa Hiroyuki Kohno Rikiya Kitagawa 《Journal of polymer science. Part A, Polymer chemistry》1989,27(2):487-495
Polymerizable carbamates were synthesized from 3-vinylphenyl and 2-methacryloyloxyethyl isocyanates and perfume and herbicide alcohols, such as 2-phenethyl alcohol, citronellol, geraniol, 1-menthol, borneol, and 2-(2,4-dichlorophenoxy)- and 2-(2,4,5-trichlorophenoxy)ethyl alcohols. Copolymerization of these carbamate monomers and N-vinyl-2-pyrrolidone with AIBN in dioxane gave respective copolymers. Hydrolyses of both monomers and copolymers, however, required severe acid conditions, although different chemical structures gave different hydrolytic behaviors. 相似文献
58.
In order to investigate the reason why phenylpropanoic acid derivative (KCL), a potent, human peroxisome proliferator-activated receptor (PPAR) alpha-selective agonist, shows this selectivity, we analyzed the binding modes of KCL and a related compound to the ligand-binding domain of human PPARalpha and rat PPARalpha by means of computer-aided molecular modeling. We concluded that the characteristic specificity of KCL is due to a specific hydrophobic contact between the hydrophobic tail part (the 4-trifluoromethyl group) and the key amino acid Ile272 located on the helix three region of the human PPARalpha ligand binding domain. We propose a possible binding mode of KCL with the ligand-binding domain of human PPARalpha. This binding model should offer important insights for further structural design of subtype-selective PPARalpha agonists for the treatment of altered metabolic homeostasis, such as dyslipidemia, obesity, and diabetes. 相似文献
59.
Hiroyuki Koshino Hiroyuki Osada Tatsuya Yano Jun Uzawa Kiyoshi Isono 《Tetrahedron letters》1991,32(52):7707-7710
The structures of enopeptins A and B, novel depsipeptide antibiotics with 1,3,5,7,9-decapentaene-1,10-dicarboxylic acid and 2-amino-3-hydroxycyclopent-2-enone in a side chain, were determined by chemical and spectroscopic means. 相似文献
60.
Naruki Tahara 《Tetrahedron letters》2004,45(26):5117-5120
Sequential treatment of 4,4-dimethyl-2-(o-tolyl)oxazoline in THF with sec-BuLi, aromatic or aliphatic aldehydes, sec-BuLi, B(OMe)3, and H2O2 produced the laterally alkylated and ortho-hydroxylated oxazolines in one-pot. Treatment of these products with TFA in aqueous THF provided 3-substituted 8-hydroxy-3,4-dihydroisocoumarins in 44-75% overall yields. This procedure allowed the short synthesis of (±)-hydrangenol and (±)-phyllodulcin, naturally occurring 3,4-dihydroisocoumarins of pharmacological interest. A more economical synthesis of (±)-phyllodulcin via the trianion intermediate is also described. 相似文献