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101.
Prof. Zhijian Chen Yong Liu Wolfgang Wagner Dr. Vladimir Stepanenko Dr. Xiangkui Ren Dr. Soichiro Ogi Prof. Frank Würthner 《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2017,129(21):5823-5827
A new amphiphilic BF2-azadipyrromethene (aza-BODIPY) dye 1 has been synthesized using a CuI-catalyzed “click” reaction. For this dye, two self-assembly pathways that lead to different type of J-aggregates with distinct near-infrared optical properties have been discovered. The metastable off-pathway product displays a broad, structureless absorption band while the thermodynamically stable on-pathway aggregate exhibits the characteristic spectral features of a J-aggregate, that is, red-shifted intense absorption band with significantly narrowed linewidth. The morphology and structure of the aggregates were studied by atomic force microscopy, transmission and scanning electron microscopy. The aggregation processes of 1 were investigated by temperature- and concentration-dependent UV/Vis spectroscopy and evaluated by models for cooperative self-assembly. 相似文献
102.
Some new N-monocarbamoyl symmetrical diamines have been prepared by the addition of symmetrical amines to isocyanates or isothiocyanates. 2,6-Diaminopyridine (1), (1R,2R)-1,2-diaminocyclohexane [(1R,2R)-2], meso-1,2-diaminocyclohexane (meso-2), or (1R,2R)-1,2-diphenylethylenediamine (3) were used as the starting symmetrical diamine frameworks. All of the newly synthesized compounds were subjected to an evaluation of antiviral activity with herpes simplex virus (HSV)-1. N-Monocarbamoyl 2,6-diaminopyridines (5a, b) showed significant antiviral activity (EC(50)=17.0, 6.2 microg/ml) comparable to that of N-monododecanoyl 2,6-diaminopyridine (A2). As a result, compound 5a showed a better selectivity index (CC(50)/EC(50) = ca. 10.0) than that of A2. 相似文献
103.
Ando K Akai Y Kunitomo J Yokomizo T Nakajima H Takeuchi T Yamashita M Ohta S Ohishi T Ohishi Y 《Organic & biomolecular chemistry》2007,5(4):655-663
A novel seven-membered lactam formation method has been established by intramolecular ring closure reaction of 4-bromo-(E)-3-[(2-alkylvinyl)carbonylamino]benzo[b]furans under Heck coupling conditions. A number of furo[2,3,4-jk][2]benzazepin-4(3H)-ones, tricyclicbenzo[b]furans, have been prepared by this method and evaluated for their leukotriene B(4) (LTB(4)) receptor and poly(ADP-ribose)polymerase-1 (PARP-1) inhibitory activities. 相似文献
104.
Soichiro Kyushin Masanobu Ikarugi Kazutoshi Takatsuna Midori Goto Hideyuki Matsumoto 《Journal of organometallic chemistry》1996,510(1-2):121-133
Dibenzo[b,e]-7,7,8,8-tetraalkyl-7,8-disilabicyclo[2.2.2]octa-2,5-dienes (1: R = tBuCH2; 2: R = iPr) were prepared by the reaction of ClR2SiSiR2Cl with lithium anthracenide in 1,2-dimethoxyethane (DME) at room temperature. The structure of 1 was determined by X-ray crystallography. Crystal data for 1: monoclinic, rC2/c, A = 12.941(2), B = 14.601(1), C = 35.109(6) Å, β = 94.957(7)°, V = 6609(2) Å3, Z= 8, R = 0.048, Rw = 0.053 for 4037 reflections. Compounds 1 and 2 show the bathochromic shift of 1La and 1Lb bands in UV spectra and exhibit considerably low oxidation potentials due to effective σ-π conjugation. Compounds 1 and 2 form charge-transfer complexes with tetracyanoethylene (TCNE). In the case of 1, the charge-transfer complex (1: TCNE = 2: 1) could be isolated as crystals and the structure was determined by X-ray crystallography. Crystal data for the 1-TCNE complex: monoclinic, C2/c, A= 10.267(2), b = 36.077(4), C = 20.022(4) Å, β = 100.680(8)°, V = 7288(2) Å3, Z = 4, R = 0.045, Rw = 0.077 for 4120 reflections. The action of transition metal chlorides on 2 resulted in [4+2] cycloreversion to form CliPr2SiSiiPr2Cl and anthracene. 相似文献
105.
Y Takeda K Kawagoe A Yokomizo Y Yokomizo T Hosokami Y Shimoto Y Tabuchi Y Ogihara Y Honda K Kawarabayashi M Iseri S Yokohama 《Chemical & pharmaceutical bulletin》1999,47(6):755-771
In order to improve the biological characteristics of DA-3934 (5), a novel gastrin/cholecystokinin (CCK)-B receptor antagonist, phenoxyacetic acid derivatives replacing the N-methyl-N-phenylcarbamoylmethyl moiety of 5 with various alkyl chains have been synthesized and their biological activity evaluated. The relationship between the structure of these compounds and their human gastrin receptor binding affinity showed that there should be the optimal size among the various N-alkyl chains. Also a significant increase in the receptor binding affinity was achieved by several compounds. Among those compounds, 2-[3-[3- [N-cyclohexylmethyl-N-[2-(N-methyl- N-phenylcarbamoylmethoxy)phenyl]carbamoylmethyl]ureido]pheny l]acetic acid (22c) and (+/-)-2-[3-[3-[N-[2-(N-methyl-N- phenylcarbamoylmethoxy)phenyl]-N-(3-methylpentyl)carbamoy lmethyl]ureido] phenyl]acetic acid (22h) exhibited high affinity for human gastrin receptors and were also more potent inhibitors in a pentagastrin-induced gastric acid secretion model than the parent compound, 5. The ED50 values of these compounds when administered intraduodenally to rats were 0.12 and 0.63 mg/kg, respectively. 相似文献
106.
107.
108.
We consider the Cauchy problem for quadratic nonlinear Klein‐Gordon systems in two space dimensions with masses satisfying the resonance relation. Under the null condition in the sense of J.‐M. Delort, D. Fang, and R. Xue (J. Funct. Anal. 211 (2004), no. 2, 288–323), we show the global existence of asymptotically free solutions if the initial data are sufficiently small in some weighted Sobolev space. Our proof is based on an algebraic characterization of nonlinearities satisfying the null condition. © 2012 Wiley Periodicals, Inc. 相似文献
109.
Mibu Nobuko Ohata Tomonori Sano Marina Zhou Jian-Rong Yokomizo Kazumi Aki Hatsumi Sumoto Kunihiro 《Journal of Thermal Analysis and Calorimetry》2019,135(5):2807-2811
Journal of Thermal Analysis and Calorimetry - In our search for new bioactive compounds that interfere with the sugar recognition process, we have designed and synthesized C3- and Cs-symmetrical... 相似文献
110.
Matsumoto M Inukai J Tsutsumi E Yoshimoto S Itaya K Ito O Fujiwara K Murata M Murata Y Komatsu K 《Langmuir : the ACS journal of surfaces and colloids》2004,20(4):1245-1250
Scanning tunneling microscopy (STM) and low-energy electron diffraction were used to reveal the structures of ordered adlayers of [2+2]-type C60-C60 fullerene dimer (C120) and C60-C70 cross-dimer (C130) formed on Au(111) by immersingit in abenzene solution containing C120 or C130 molecules. High-resolution STM images clearly showed the packing arrangements and the electronic structures of C120 and C130 on the Au(111) surface in ultrahigh vacuum. The (2 square root3 x 4square root3)R30 degrees, (2square root3 x 5square root3)R30 degrees, and (7 x 7) structures were found for the C120 adlayer on the Au(111) surface, whereas C130 molecules were closely packed on the surface. Each C60 or C70 monomer cage was discerned in the STM image of a C130 molecule. 相似文献