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[reaction: see text] A series of oligo(octithienylene-diethynylene)s alternately composed of octithiophene and diacetylene units have been prepared by a random Eglinton coupling reaction among mono- and diethynyloctithiophenes. The largest compound isolated in the oligomeric series is comprised of twelve octithiophene units and eleven diacetylene units, and its molecular length reaches ca. 43 nm, which is the longest among single-component conjugated nanomolecules. 相似文献
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One‐Pot Synthesis of 3‐Acetyl‐2‐aryl‐3,4‐dihydroquinazolines from N‐[2‐(Azidomethyl)phenyl]benzamides Utilizing Intramolecular Aza‐Wittig Reaction 下载免费PDF全文
Kazuhiro Kobayashi Naoki Matsumoto Mika Nagashima Hiroki Inouchi 《Helvetica chimica acta》2015,98(2):184-189
A new and convenient method for the preparation of 3,4‐dihydroquinazolines 5 with aryl and Ac groups at C(2) and N(3), respectively, has been developed. The key sequence is the formation of aza‐phosphorane intermediates by the reaction of N‐[2‐(azidomethyl)phenyl]benzamides 1 with Ph3P, followed by intramolecular aza‐Wittig reaction and 3‐acetylation, which can be conducted in one‐pot. 相似文献
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Generation of Aryl(2‐lithiophenyl)methanone O‐Methyl Oximes and Their Use for the Synthesis of N‐(3‐Alkyl‐1‐aryl‐ or 1,3‐diaryl‐1H‐isoindol‐1‐yl)‐O‐methylhydroxylamines via the Reaction with Nitriles 下载免费PDF全文
Kazuhiro Kobayashi Kota Matsumoto Yuu Shirai Hiroaki Ishikawa Hiroki Inouchi Miyuki Tanmatsu 《Helvetica chimica acta》2014,97(7):915-922
An efficient two‐step procedure for the preparation of a new type of 1H‐isoindoles, i.e., N‐(3‐alkyl‐1‐aryl‐ or 1,3‐diaryl‐1H‐isoindol‐1‐yl)‐O‐methylhydroxylamines 5 , from readily available aryl(2‐bromophenyl)methanones 1 has been developed. Aryl(2‐bromophenyl)methanone O‐methyloximes 2 , derived from the corresponding ketones, were treated with BuLi in Et2O at 0° to generate novel lithium compounds, aryl(2‐lithiophenyl)methanone O‐methyloximes 3 , which were allowed to react with nitriles to give the desired products 5 in moderate‐to‐fair yields. 相似文献
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Toshifumi Inouchi Dr. Takuya Nakashima Dr. Masaya Toba Prof. Tsuyoshi Kawai 《化学:亚洲杂志》2011,6(11):3020-3027
T‐shaped π‐conjugated molecules with an N‐methyl‐benzimidazole junction have been synthesized and their acid‐responsive photophysical properties owing to the change in the π‐conjugation system are discussed. T‐shaped π‐conjugated molecules consist of two orthogonal π‐conjugated systems including a phenyl thiophene extended from the 2‐position and alkyl phenylenes connected through various π‐spacers from the 4,7‐positions of the N‐methyl‐benzimidazole junction. The π‐spacers, such as thiophene, ethyne, and ethane, have an effect on the acid response of photophysical properties in terms of changes in conformation, excited‐state energy and charge‐transfer (CT) characteristics. In particular, the π‐conjugated molecule with ethynyl spacers exhibited a marked redshift in the fluorescence spectrum with a large Stokes shift upon the addition of acid, whereas the other molecules showed substantial quenching. The redshift in emission was studied in detail by temperature‐dependent fluorescence measurements, which indicated the transition to a CT state over the finite activation energy at the excited state. The change in the frontier molecular orbitals upon acid addition was further discussed by means of DFT calculations. 相似文献
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Akikazu Matsumoto Sachiyo Umehara Hiroyuki Watanabe Takayuki Otsu 《Journal of Polymer Science.Polymer Physics》1993,31(5):527-535
Poly(N-n-butylitaconimide) was prepared by radical polymerization in benzene and in bulk at 60°C and was subsequently fractionated at 30°C with benzene and methanol as solvent and nonsolvent, respectively. Relationships between molecular weight and intrinsic viscosity (Mark-Houwink-Sakurada equations) in tetrahydrofuran, benzene, and toluene at 30°C are established. From the Burchard-Stockmayer-Fixman plot, the characteristic ratio of this polymer is determined, and local chain conformation is discussed in relation to the termination process in radical polymerization. © 1993 John Wiley & Sons, Inc. 相似文献
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Reaction profiles and energetics for the reactions of substituted benzaldehydes with a series of different simple metal hydrides (BH(3), BMeH(2), BMe(2)H, AlH(3), and AlMe(2)H) are examined computationally. B3LYP/6-31G optimizations and MP2/6-311G single point energy calculations revealed that the Al reagents are more reactive than B reagents. Replacement of H with Me on BH(3) or AlH(3) makes the reduction transition state (TS) less stable. Accordingly the overall reactivity is in the order AlH(3) > AlMe(2)H > BH(3) > BMe(2)H. The Hammett rho value for substituted benzaldehydes (BAs) is negative for the initial complex formation and positive for the hydride-transfer step. The size and the sign of the apparent rho value depend on the relative stabilities of the separated reactants and the complex. The TS structures vary according to the Hammond postulate for substituted BAs and the variation is reflected in carbonyl-carbon and aldehyde-deuterium isotope effects. Comparison of the reaction profiles of the monomer and dimer reagents reveals that the real reacting species is the monomer in the gas phase for BH(3) but the dimer for BMe(2)H. 相似文献
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Naomi Daikuhara Sachiyo Yamaki Surattana Amnuoypol Naoki Saito 《Tetrahedron letters》2009,50(29):4276-314
Two new bistetrahydroisoquinoline marine natural products, renieramycins T (1) and U (2), were isolated from the Thai blue sponge Xestospongia sp. and their structures were elucidated by comparing spectral data with those of renieramycin M (3a) and ecteinascidin 770 (4a). These compounds are the first reported examples of novel ecteinascidin-renieramycin hybrid natural products. Renieramycin T (1) showed strong cytotoxicity to several human cancer cell lines, its IC50 values ranging from 4.7 to 98 nM. 相似文献
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Sachiyo Terada 《European Journal of Combinatorics》2000,21(8):1073
We show that for the split and non-split extensions ofFq2bySL (2, q) (q = 2e,e ≥ 3), the group association schemes have the same parameters but are not isomorphic. For the split and non-split extensions ofFq2by the standard Borel subgroup of SL(2,q ) (q = 2e, e ≥ 3), the group association schemes are shown to be isomorphic. 相似文献
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Le Hoang Lam Tomoko Shimamura Sachiyo Manabe Munetaka Ishiyama Hiroyuki Ukeda 《Analytical sciences》2008,24(8):1057-1060
A newly synthesized substrate, 3-hydroxybutyrylglycyl-glycyl-glycine (3HB-GGG), was applied to the assay of ACE-inhibiting activity to overcome the smaller selectivity and sensitivity of the conventional method. In this study, an ACE-inhibiting assay was improved by the use of a water-soluble tetrazolium salt, 4-[3-(4-iodophenyl)-2-(4-nitrophenyl)-2H-5-tetrazolio]-1,3-benzene disulfonate sodium salt (WST-1), for the detection of 3-hydroxybutyrate, derived from 3HB-GGG. The optimized conditions were as follows: 0.333 mM NAD(+), 0.333 mM WST-1, 0.1 mM EDTA, 0.633 U ml(-1) diaphorase, and 0.700 U ml(-1) 3-hydroxybutyrate dehydrogenase. The developed assay was efficiently applicable to evaluate the ACE-inhibiting activity of practical ACE inhibitors. 相似文献