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991.
The nmr spectroscopic studies on methoxybocconine are described. The spectral data indicate bocconine to be 2,3,7,8-bis(methylenedioxy)-10-methoxy-5-methylbenzo[c]phenanthridine. 相似文献
992.
Yoshio Hamashima Sadao Yamamoto Shoichiro Uyeo Mitsuru Yoshioka Masayuki Murakami Hisao Ona Yasuhiro Nishitani Wataru Nagata 《Tetrahedron letters》1979,20(28):2595-2598
Reaction of 2β-unsubstituted or functionalized-methyl 6-epipenicillin sulfoxides with tervalent phosphorus compounds gave azetidinone-epi-oxazolines , important intermediates in synthesis of 7α-methoxy-1-oxacephems. Preparation of the 2β-functionalized-methyl substrates is described also. 相似文献
993.
Poisson statistics is a nature consequence of a distribution of solubilized molecules among micellar aggregates. With postulates of non-cooperativity and thermodynamic considerations, relationships for extent of solute fractionation between the micellar phase and the aqueous phase are derived, as are expressions for the handling of experimental data from the quenching of photoluminescence probes of micellar aggregates. 相似文献
994.
Masayuki Kawakami Kiyoshi Mizuno Satoru Kunii Tadao Kasuya Hirochika Enokiya Kiyoshi Kume 《Journal of magnetism and magnetic materials》1982,30(2):201-208
The 11B nuclear magnetic resonance in a dense Kondo system CeB6 has been observed by the spin echo technique below 4.2 K at fixed frequencies of 2.5, 6.5, 13.33 and 18.00 MHz, which correspond to magnetic fields of 1.83, 4.76, 9.76 and 13.18 KOe for the free 11B nucleus, respectively. The spectra in the phase II appeared to have two peaks in the magnetic field applied in the [111] direction, the spacing of which was found to be very small in zero external field and increased monotonically (up to 0.11 kOe at 2.6 K) with increasing field. On the other hand, the spectra in the phase III were complex. Especially, the spectra observed for [111] at 6.5 MHz were found to spread over 1.9 KOe and to have several peaks. From comparison between the experiments and the dipolar field calculation based on the recent neutron diffraction measurements, possible magnetic structures were examined for the phases II and III. 相似文献
995.
Peptide mimics derived from the first extracellular loop of CCR5 bearing non-peptide spacers in place of Ala-Ala-Ala sequence in the peptide moiety were synthesized, and the effects of these compounds on the inhibition against HIV-1 were examined. Compound 2b having m-aminophenoxyacetic acid derivative as a non-peptide spacer significantly inhibited HIV-1. 相似文献
996.
We stabilized the relative carrier-envelope phase slip among the pump pulse and its subharmonic signal and idler pulses in a femtosecond optical parametric oscillator, resulting in long-term phasecoherence among the pulses. The stabilized beat signal corresponding to the relative carrier-envelope phase slip among subharmonic pulses had an accumulated phase error of 0.24 rad in the 1-mHz-1-MHz region. The fluctuation of the beat frequency measured by a 1-s-averaged counter was less than 1 mHz in a 1480-s measurement. 相似文献
997.
Tsuji E Ando K Kunitomo J Yamashita M Ohta S Kohno S Ohishi Y 《Organic & biomolecular chemistry》2003,1(18):3139-3141
Novel 3-acetoacetylaminobenzo[b]furan derivatives with a modified triene system at the 3-position were prepared through acylation of the 3-aminobenzo[b]furans with 5-methylisoxazole-4-carboxylic acid chloride followed by basic cleavage of the isoxazole ring and several of these compounds showed moderate cysteinyl leukotriene receptor 2 antagonistic activity. 相似文献
998.
999.
1000.
It was found that a one-dimensional rodlike structure of 5,10,15,20-tetrakis(4-sulfonatophenyl)porphyrin (TPPS) in water acts as a powerful template for electrochemical polymerization of ethylenedioxathiophene (EDOT) and pyrrole on an ITO electrode. Examination using CV and UV-vis spectroscopic examinations established that J-aggregated TPPS molecules are entrapped in the resultant poly(EDOT) and poly(pyrrole) films. SEM observation established that these monomers are electrochemically oxidized to grow up to a nanosized rodlike structure, reflecting the aggregation structure of TPPS. [structure: see text] 相似文献