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191.
The reaction of dimethyl(methylthio)sulfonium trifluoromethanesulfonate (DMTST) with o-allylphenol gave 2-methylthiomethyl-2,3-dihydrobenzofuran in 97% yield. The reaction of DMTST with N-tosyl-o-isopropenylanilide followed by the addition of aq sodium carbonate afforded N-tosyl-3-methylindole in 88% yield, whereas N-tosyl-o-vinylanilide afforded N-tosylindoline in 85% yield. 相似文献
192.
Seunghee Jung Yuki TsukudaRie Kawashima Takumi IshikiAyaka Matsumoto Aya NakaniwaMiho Takagi Takuya NoguchiNobuyuki Imai 《Tetrahedron letters》2013
Acetaminophen analogues containing α-amino acid and fatty acids were easily synthesized in 77–99% yields from the corresponding mixed carbonic carboxylic anhydrides of α-amino acid and fatty acids using aniline derivatives in aqueous MeCN. 相似文献
193.
[reaction: see text] The enantioselective conjugate addition reaction of Et(2)Zn to Meldrum's acid derived acceptors, mediated by a catalyst formed from Cu(O(2)CCF(3))(2) and a phosphoramidite ligand, is reported. Adducts are obtained in useful yields and up to 94% ee. 相似文献
194.
Tsutomu Kumagai Takumi Nittono Noriyuki Tanaka Toshio Mukai 《Tetrahedron letters》1985,26(49):6093-6096
Upon irradiation, 2-dicyanomethylenebenzonorbornene f was converted into 1-dicyanomethylenebenzobicyclo[3.1.1]heptene . The reaction pathway is discussed with reference to the photoreaction of parent hydrocarbon. 相似文献
195.
Tsutsui H Abe T Nakamura S Anada M Hashimoto S 《Chemical & pharmaceutical bulletin》2005,53(10):1366-1368
An efficient and reliable procedure for the preparation of dirhodium(II) tetrakis[N-phthaloyl-(S)-tert-leucinate], Rh2(S-PTTL)(4), a universally effective catalyst for a range of enantioselective carbene transformations, is described. The N-phthaloylation of (S)-tert-leucine by the method of Bose with essentially no racemization is a key to this process. 相似文献
196.
Tetsuya Ishida Makoto Sakakibara Yoshio Ueno Kan-Ichi Hasegawa 《Journal of heterocyclic chemistry》1989,26(3):785-788
The condensation of 2-bromo- or 2, 6-dibromo-4, 8-bis(alkylamino)-1, 5-naphthoquinones with zinc 2-amino-benzeneselenolates gave 1, 5-bis(alkylamino)-4H-benzo[a]phenoselenazin-4-one and the 3- and/or 10-substituted compounds. These phenoselenazone derivatives absorb nearly infrared light and can be used as optical recording media for a laser beam. 相似文献
197.
A Nakamura S Nagai T Ueda N Murakami J Sakakibara H Shibuya I Kitagawa 《Chemical & pharmaceutical bulletin》1991,39(7):1726-1730
Monensylglycine (2a) was lactonized to macrocyclic monensylglycine-1,29-lactone (3a) by Corey's method. Lactonization of monensylamino acids (2b--d) to monensylamino acid-1,29-lactones (3b--d) was carried out by utilizing the template effect of K+ ion. Monobenzyl esters of dicarboxylic monensylamino acids (5e--f) also were lactonized followed by debenzylation to yield carboxylic monensylamino acid-1,29-lactones (3e--f). Sodium ion transport activity of monensin (1) and the lactones (3) was measured in a liquid membrane and in guinea pig erythrocyte membrane. Monensylaspartic acid-1,29-lactone (3e) exhibited 2.5 times higher activity than 1 in the liquid membrane. Monensylalanine-1,29-lactone (3b), monensylphenylalanine-1,29-lactone (3c), and monensyltyrosine-1,29-lactone (3d), having smaller Na+ ion transport activity than 3e, showed weak antibacterial activity, while 3e was inactive in biological tests, probably due to the lower lipophilicity. 相似文献
198.
球壳粒子悬浮系模型化研究——内部相参数对介电谱影响的数值模拟 总被引:2,自引:0,他引:2
在Hanai理论基础上对球壳粒子悬浮系的介电模型进行了模拟研究,通过用C++的复数类对理论公式的程序化,建立了介电谱的介电参数与体系内部相参数的关系.所得的解析解可方便地模拟介电弛豫谱依不同相参数的变化曲线,计算并分析了内部参数对介电谱的模式以及介电参数的影响因素. 相似文献
199.
A new acetylenic compound from the rhizomes of Atractylodes chinensis and its absolute configuration
Nakai Y Sakakibara I Hirakura K Terabayashi S Takeda S 《Chemical & pharmaceutical bulletin》2005,53(12):1580-1581
A new acetylenic compound "atractyloyne", (3S,4E,6E,12E)-1-isovaleryloxy-tetradeca-4,6,12-triene-8,10-diyne-3,14-diol (1) was isolated from the rhizomes of Atractylodes chinensis (Compositae) together with a known compound (4E,6E,12E)-3-isovaleryloxy-tetradeca-4,6,12-triene-8,10-diyne-1,14-diol (2). These structures were determined on the basis of the spectroscopic data and chemical evidence, and the absolute configuration of 1 was established by the modified 2-methoxy-2-trifluoromethylphenylacetic acid (MTPA) method. 相似文献
200.
Nagatsu A Sugitani T Mori Y Okuyama H Sakakibara J Mizukami H 《Natural product research》2004,18(3):231-239
A simple but novel compound, S-1-methoxy-1-(3,5-dimethoxy-4-hydroxyphenyl)ethane, was isolated as a moderately antioxidative compound from rape (Brassica campestris L. subsp. napus) oil cake together with 5 known compounds. Three of these compounds, indolacetonitrile, 4-hydroxyindolacetonitrile, and 4-hydroxyphenylacetonitrile, showed strong antioxidative activity evaluated by the ferric thiocyanate method. 相似文献