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排序方式: 共有117条查询结果,搜索用时 15 毫秒
1.
Takeshi Satake Yasunobu Onishi Masahiko Iyoda Masazumi Nakagawa 《Tetrahedron letters》1979,20(34):3171-3172
Tri-t-butylcarboxybisdehydro[14]annulene was converted by the Curtius reaction into unstable aminoannulene, which could be characterized as N-acetyl derivative. The pKa-value of the aminoannulene reflects aromatic nature of the annulene nucleus. 相似文献
2.
Hiroyuki Ishibashi Motofumi Okada Atsuko Akiyama Kazuyuki Nomura Masazumi Ikeda 《Journal of heterocyclic chemistry》1986,23(4):1163-1166
2,3-Dihydro-5H-1,4-benzoxathiepins were prepared by intramolecular Friedel-Crafts reactions of ethyl α-[2-(aryloxy)ethylthio]-α-chloroacetates or by acid-catalyzed cyclizations of ethyl α-[2-(aryloxy)ethylsulfinyl]-acetate. 1,2,3,5-Tetrahydro-4,1-benzothiazepines were similarly prepared. 相似文献
3.
Yasumitsu Tamura Yasuyoshi Miki Yoshinori Nishikawa Masazumi Ikeda 《Journal of heterocyclic chemistry》1976,13(2):317-320
N-Aminophenanthridinium salt reacted with dimethyl acetylenedicarboxylate in the presence of potassium carbonate to give a 3,3a-dihydropyrazolo[1,5-f]phenanthridine but with mono-substituted acetylenes (ethyl propiolate and benzoylacetylene) it produced aromatized pyrazolo-[1,5-f]phenanthridines (XII and XIII). The reaction of the N-benzoylimine with di-substituted acetylenes (dimethyl acetylenedicarboxylate and methyl phenylpropiolate) and mono-substituted acetylenes (ethyl propiolate and benzoylacetylene) yielded 1,3a-dihydropyrazolo[1,5-f]phenanthridines and the aromatized products (XII and XIII), respectively. 相似文献
4.
5.
Yasuyoshi Miki Sanae Yagi Hiroko Hachiken Masazumi Ikeda 《Journal of heterocyclic chemistry》1993,30(4):1045-1046
Reaction of pyrazolo[1,5-a]pyridines with aldehydes in the presence of trifluoroacetic acid gave bis[pyrazolo[1,5-a]pyrid-3-yl)methanes in high yields. 相似文献
6.
Hiroyuki Ishibashi Hajime Komatsu Kazumi Maruyama Masazumi Ikeda 《Tetrahedron letters》1985,26(47):5791-5794
A Pummerer rearrangement product, 4-chlorophenylthiomethyl trifluoroacetate (6), obtained from 4-chlorophenyl methyl sulfoxide (5) and trifluoroacetic anhydride, reacted with 1-alkenes in trifluoroacetic acid to give the ene products 8, which were readily converted into the terminal 1,3-dienes 10 by oxidation and subsequent pyrolysis. Using this method, 9,11-dodecadien-1-yl acetate (12), a sex pheromone of the red bollworm moth, was synthesized. 相似文献
7.
Nakamura K Suzuki T Hasegawa M Kato Y Sasaki H Inouye K 《Journal of chromatography. A》2003,1009(1-2):133-139
An affinity sorbent, hydrophilic polymer-based carrier of different pore size (Toyopearl) with immobilized p-aminobenzamidine (ABA), has been prepared. Its basic properties and some applications for protein purification were studied. ABA, which is a synthetic inhibitor for trypsin-like proteases, was covalently immobilized to Toyopearl by reductive amination. The ligand density and binding capacity for porcine trypsin varied depending on the pore size of Toyopearl. The maximum binding capacity of the immobilized p-aminobenzamidine Toyopearl (ABA-Toyopearl) for trypsin was more than 40 mg/ml gel. ABA-Toyopearl thus obtained was very stable below pH 8 and was successfully used for high-performance affinity chromatography of trypsin-like proteases such as trypsin, thrombin, tissue-type plasminogen activator or urokinase in a single step at 25 degrees C. 相似文献
8.
Hiroyuki Ishibashi Iwao Takamuro Yo-Ichi Mizukami Maki Irie Masazumi Ikeda 《合成通讯》2013,43(3-4):443-452
Friedel-Crafts acylation of arenes with methylthio- (1) or phenylthio-acetyl chloride (2) provides ready access to α-methylthio- or α-phenylthio-substituted acetophenones. The acyl chlorides 1 and 2 reacted also with organoaluminum reagents to give α-sulfenylated alkanones. 相似文献
9.
Keiichi Tomishige Masazumi Tamura Yoshinao Nakagawa 《Chemical record (New York, N.Y.)》2014,14(6):1041-1054
The catalytic performance of ReOx‐modified Ir metal catalyst in the hydrogenolysis of C–O bonds is strongly dependent on the choice of solvent. The acidic property of the Re species becomes obvious in the alkane solvent, and the hydrogenolysis reaction proceeds mainly by acid‐catalyzed dehydration and the subsequent metal‐catalyzed hydrogenation. The acidic property of the Re species is weakened in water; however, the hydrogenolysis reaction proceeds in water via a direct mechanism involving SN2‐like attack of a hydride species at the interface between Ir and ReOx on the adsorbed Re alkoxide species. This mechanism enabled the selective dissociation of the C–O bond neighboring the CH2OH group. 相似文献
10.
Synthesis of naphtho-tri-t-butyltrisdehydro[16]annulene containing a hexapentaene and an acetylene units has been described. It was found that the [16]annulene is less stable and the paratropicity is much stronger as compared with previously reported isomeric naphtho[16]-annulene containing a diacetylene and a butatriene linkage. 相似文献