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101.
The copper(II) complex with N,N-bis(2-benzimidazolylmethyl)benzylamine has been synthesized and its crystal structure was determined by X-ray diffraction methods. 相似文献
102.
Preliminary communicationPalladium-catalyzed carboxylation of aromatic compounds with carbon dioxide
Hiroshi Sugimoto Itaru Kawata Hiroshi Taniguchi Yuzo Fujiwara 《Journal of organometallic chemistry》1984,266(3):c44-c46
Carbon dioxide has been found to react with aromatic compounds such as benzene, anisole, furane, and thiophene to give aromatic acids in modest yields with palladium(II) salts as catalysts. The addition of t-BuOOH increases the yield. 相似文献
103.
4-Diazomethyl-substituted coumarins, 1-methyl-2(1H)-quinolinones, 1 -thiocoumarin and their tricyclic analogs were found to be easily cyclized into the corresponding pyrazole isomers condensed with heteroaromatics. Thermodependent feature of these conversions and the remarkably accelerating effect of the alkyl substituent peri to the diazomethyl group were realized. Some other diazomethyl compounds connected with 2-pyridinone, 3-pyrazolone, chromone and 1-thiochromone were prepared, and their stability and thermal properties were compared. 相似文献
104.
K Osawa H Yasuda T Maruyama H Morita K Takeya H Itokawa 《Chemical & pharmaceutical bulletin》1992,40(11):2970-2974
The methanolic extract of Swartzia polyphylla DC. heartwood had antibacterial activity against cariogenic bacteria, the mutans Streptococci. The chromatographic purification of the extract afforded seven flavonoids. Among them, three known isoflavanones, dihydrobiochanin A, ferreirin and darbergioidin, and one new isoflavanone, 5,2',4'-trihydroxy-7-methoxyisoflavanone (dihydrocajanin) had potent antibacterial activity against cariogenic bacteria. This effect was not detected on isoflavone derivatives. A comparative antibacterial study of various flavonoids was further performed, and their structure-activity relationship was discussed. 相似文献
105.
Arao Nakamura Yuzo Yoshikuni Yuzo Ishida Shigeo Shionoya Masaki Aihara 《Optics Communications》1983,44(6):431-436
Photon-echo behavior in the ultrashort time region is studied for pentacene molecules in p-terphenyl crystals at 1.7 K by means of the accumulated three-pulse echo. We show highly resolved echo spectra with a parameter of time separation and also time behavior of echo intensity as a function of pulse separation measured at various frequencies near the peak position of the absorption line of the S0–S1 transition. We demonstrate various features of echo profile in both time and frequency domains, which are dependent on the time region of observation. 相似文献
106.
107.
Y. Harada K. Murano I. Shirotani T. Takahashi Y. Maruyama 《Solid State Communications》1982,44(6):877-879
The X-ray photoelectron spectrum of black phosphorus has been measured for the first time. The features in the valence band spectrum are found to be in good agreement with those of the valence state density recently calculated on the basis of a pseudopotential method. The 2s and 2p core spectrum of black phosphorus is also discussed. 相似文献
108.
Sadao Nakajima Kyoko Kosasa Yoshio Maruyama Seichi Kawai 《Spectrochimica Acta Part B: Atomic Spectroscopy》1982,37(8):685-690
The behavior of powdered samples in the region behind the incident and reflected shock wave were investigated. When the particle size is less than 8 μm, the powdered samples are effectively vaporized and excited to emit spectral lines. It was shown that the sample particles are scattered behind the incident wave and concentrated again in a narrow portion near the observation window by the use of a reflector so that intense emission can be attained. As an excitation source, the shock tube was used for the determination of trace metals contained in copper oxide. 相似文献
109.
Taketoshi Makino Tetsuji Nunozawa Naomichi Baba Junichi Oda Yuzo Inouye 《Tetrahedron letters》1979,20(19):1683-1686
Asymmetric reduction of α-ketoester with a chiral dihydronicotinamide was significantly affected by chiral aromatic additives, capable of exerting an attractive interaction with dihydropyridine ring, which was further consolidated through with magnesium. 相似文献
110.
The electrochemical behavior of ten nitrogen heterocycles was investigated in DMF-water and aqueous buffer solution. On the basis of these data, the effect of proton on the reduction behavior in DMF-water media and the reduction pathway in aqueous buffer solution ware phenomenologically classified. The adsorption phenomena in aqueous buffer solution and the correlation of reduction behavior with structure and reactivity were discussed. The structure of electrolytic products was also estimated and identified by negative electron density distributions of radical anion, GC-MS and spectrophotometry. 相似文献