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1.
T Oh-Hara Y Ikeda H Sakagami K Konno T Kaiya K Kohda Y Kawazoe 《Chemical & pharmaceutical bulletin》1990,38(1):282-284
We have found that water-soluble extracts of lignified natural products are strong potentiaters of hemolytic plaque-forming cell production in mice. Apparently, the active components involved belong to a lignin family. Consequently, study of medicinal potential, especially immunopotentiating capacity, of lignified materials is important. 相似文献
2.
Synthesis and antibacterial activity of 7-[(Z)-2-(2-aminothiazol-4-yl)-2-(3-(3-hydroxy-4-pyridon-1-y l)-3- carboxypropoxyimino)acetamido]-3-(1,2,3-thiadiazol-5-yl)thio methyl-3-cephem-4-carboxylic acid (12a) and its related compounds are described. Compound 12a exhibited excellent antibacterial activity against gram-negative bacteria, including Pseudomonas aeruginosa. 相似文献
3.
[structure: see text] A second generation total synthesis of the potent antitumor agent (+)-phorboxazole A (1) has been achieved. The cornerstone of this approach comprises a more convergent strategy, involving late-stage Stille union of a fully elaborated C(1-28) macrocycle with a C(29-46) side chain. The second generation synthesis entails the longest linear sequence of 24 steps, with an overall yield of 4.2%. 相似文献
4.
Eight new homologous series of 4-alkyl-N-(4-alkloxysalicylidene)anilines were synthesized. The phase transitions of these homologues were determined using differential scanning calorimetry and polarizing optical microscopy. The homologues began to exhibit liquid crystalline phases as the terminal alkyl or alkoxyl chains were lengthened. In addition, some members of these homologues series exhibited photochromism in the solid state. 相似文献
5.
Abstract The IR absorption and Raman scattering of OBBC have been investigated in the solid, ReN, SmA and nematic phases. The intensity of the 2229 cm?1 band assigned to the C[tbnd]N stretching mode decreases with increasing temperature in the reentrant nematic phase; this is attributed to a change in the overlap of the molecules. While the IR bands at 1728 and 841 cm?1 also show a remarkable temperature dependence, Raman bands do not show significant temperature dependence in the liquid-crystal phases. 相似文献
6.
Nobuyuki Otozawa Rio Hamajima Masataka Yoshioka Raito Kato Arisa Tanaka Hiroto Fukuma Toshiki Terao Kei Manabe Syuji Fujii Yoshinobu Nakamura Atsushi Takahara Tomoyasu Hirai 《Journal of polymer science. Part A, Polymer chemistry》2020,58(14):1960-1964
This study investigates the effect of ionic liquids (ILs) on the anionic polymerization of methyl methacrylate (MMA). Polymethyl methacrylate (PMMA), an isotactic polymer, is prepared by anionic polymerization at a high reaction temperature with an IL that acts as both solvent and additive. The most plausible reaction mechanism is determined using 1H NMR and Fourier-transform infrared spectroscopy. The electrostatic interaction between MMA and the IL increases the apparent steric hindrance in MMA, resulting in the isotactic PMMA. 相似文献
7.
Prof. Dr. Christian Brückner Dr. Nivedita Chaudhri Dustin E. Nevonen Dr. Sayantan Bhattacharya Arthur Graf Elizabeth Kaesmann Dr. Ruoshi Li Dr. Matthew J. Guberman-Pfeffer Prof. Dr. Tomoyasu Mani Dr. Arunpatcha Nimthong-Roldán Dr. Matthias Zeller Dr. Adrien A. P. Chauvet Prof. Dr. Victor Nemykin 《Chemistry (Weinheim an der Bergstrasse, Germany)》2021,27(65):16189-16203
8.
Takehisa Dewa Ayumi Sumino Natsuko Watanabe Tomoyasu Noji Mamoru Nango 《Research on Chemical Intermediates》2014,40(9):3243-3256
Appropriate experimental platforms are required to clarify the structure–function relationships of membrane protein assemblies. In photosynthetic bacteria, light-harvesting complex 2 and light-harvesting/reaction center core complex play key roles in capturing and transferring light energy and facilitating subsequent charge separation. These photosynthetic apparatuses form a supramolecular assembly in the photosynthetic membrane. However, the mechanism through which this assembly influences the efficiency of energy conversion remains to be clarified. We review our recent studies that were conducted to evaluate the structure–function relationship of the supramolecular assembly of photosynthetic antenna complexes in various lipid bilayer systems, as well as the construction of novel systems of planar lipid membranes for use as experimental platforms. 相似文献
9.
Sakagami M Horie K Nakamoto K Kawaguchi T Hamana H 《Chemical & pharmaceutical bulletin》2000,48(9):1256-1263
Sialyl Lewis X (SLeX) is well known as a ligand of the cell adhesion molecule E-selectin which is specifically expressed at inflammatory lesion sites. We have synthesized several SLeX-polysaccharide conjugates and examined their potential for drug delivery to inflammatory lesions. The AUC (area under the blood concentration-time curve) 0-24 h of SLeX-CMCht (1), SLeX-CMPul (2) and SLeX-DSH (3) at the inflammatory lesion was about 60-, 300-, and 30-fold higher than that of the monovalent SLeX (7), respectively. Moreover, 1 showed 2-fold higher accumulation in the inflammatory lesion than SLN-CMCht (4), and 2 showed 2.5-fold higher accumulation than SLN-CMPul (5). 相似文献
10.
The possibility of coexistence of spherical and deformed states in samarium isotopes is explored by analyzing the experimental data of the two-neutron transfer reactions, and the moment of mixing of the coexisting states and their deformation parameters are determined. 相似文献