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91.
Two novel organotin supramolecular coordination polymers (SCP), namely, 3[Me3SnCu(CN)2·(EN)2], 1 and 3[Ph3SnCu(CN)2·(3-mpy)2], 2 are obtained by the reactions of K3[Cu(CN)4], ethyl nicotinate (EN) or 3-methylpyridine (3-mpy) and Me3SnCl or Ph3SnCl in H2O/acetonitrile solution at room temperature. 2D-layers are constructed via H-bonds between the parallel 1D-puckered chains which contain nanometer-sized [-CN(R3Sn)NC-] spacers connecting the tetrahedral (T-4) copper sites. The network structures of 1 and 2 consist of infinite layers connected by interlayer H-bonds forming 3D-framworks. 2 is the first compound in this family containing the Ph3Sn cation. The electronic absorption spectra of 1 and 2 reveal a broad band at 320 nm due to CT transition while the emission spectra exhibit high energy bands at 400-460 nm due to metal-centered (MC) transitions and low energy bands at 485-530 nm corresponding to MLCT. The 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay was used to determine the in vitro antitumor effects of the SCP 1 and 2 on human breast cancer cell line, ZR-75-1. Cell cycle analysis revealed that the SCP 1 and 2 induced apoptosis in ZR-75-1 breast cancer cell line through activating caspase-3. Moreover, in vivo model, the compound SCP 2 suppressed tumor growth developed mammary carcinoma by 52.3%. Taken together, our novel compounds selectivity exhibit specific in vivo and in vitro antitumor effects.  相似文献   
92.
The aim of the present study was to determine the content of capsaicin and dihydrocapsaicin in Capsicum samples collected from city markets in Riyadh (Saudi Arabia), calculate their pungency in Scoville heat units (SHU) and evaluate the average daily intake of capsaicin for the population of Riyadh. The investigated samples consisted of hot chillies, red chillies, green chillies, green peppers, red peppers and yellow peppers. Extraction of capsaicinoids was done using ethanol as solvent, while high performance liquid chromatography (HPLC) was used for separation, identification and quantitation of the components. The limit of detection (LOD) of the method was 0.09 and 0.10 μg/g for capsaicin and dihydrocapsaicin, respectively, while the limit of quantification (LOQ) was 0.30 and 0.36 μg/g for capsaicin and dihydrocapsaicin, respectively. Hot chillies showed the highest concentration of capsaicin (4249.0 ± 190.3 μg/g) and the highest pungency level (67984.60 SHU), whereas green peppers had the lowest detected concentration (1.0 ± 0.9 μg/g); green peppers, red peppers and yellow peppers were non pungent. The mean consumption of peppers for Riyadh city population was determined to be 15.5 g/person/day while the daily capsaicin intake was 7.584 mg/person/day.  相似文献   
93.
This paper is dedicated to a study of different extensions of the classical knapsack problem to the case when different elements of the problem formulation are subject to a degree of uncertainty described by random variables. This brings the knapsack problem into the realm of stochastic programming. Two different model formulations are proposed, based on the introduction of probability constraints. The first one is a static quadratic knapsack with a probability constraint on the capacity of the knapsack. The second one is a two-stage quadratic knapsack model, with recourse, where we introduce a probability constraint on the capacity of the knapsack in the second stage. As far as we know, this is the first time such a constraint has been used in a two-stage model. The solution techniques are based on the semidefinite relaxations. This allows for solving large instances, for which exact methods cannot be used. Numerical experiments on a set of randomly generated instances are discussed below.  相似文献   
94.
Thiation of 1 by LR gave the corresponding 3,5‐dithioxo derivative 2 and the trimer 3 . Methylation of 1 afforded the S‐methyl derivative 4 . Compound 1 was fused with 6‐bromo‐2‐phenyl‐benzo[1,3‐d]oxazin‐4‐one ( 5 ) and gave 6 . Condensation of 1 with some acid derivatives 7a , 7b , 7c , 7d and/or 8a , 8b , 8c yielded thiadiazolo‐triazine derivatives 9a , 9b , 9c , 9d and 10a , 10b , 10c . Compounds 9a , 9c and 10c were hydrolyzed to furnish 11a , 11b , 11c Acetylation of 14 afforded mono‐ and diacetyl‐derivatives 15 and 16 . Benzoylation of 14 afforded mono‐ and dibezoyl‐derivatives 17 and 18 . 14 with some aromatic aldehydes yielded 9a , 9b , 9c . Reacting 14 with phenyl (iso‐ and/or isothio‐) cyanate gave the urea derivatives 20a , 20b . Thiation of 14 with P4S10 furnished 21 . The newly synthesized compounds were tested as antimicrobial agents. J. Heterocyclic Chem., (2011)  相似文献   
95.
This paper aims to evaluate a comprehensive numerical model based on solving rate equations of a thulium-doped silica-based fiber amplifier. The pump power and thulium-doped fiber (TDF) length for single-pass thulium-doped fiber amplifiers (TDFA) are theoretically optimized to achieve the optimum gain and noise figure (NF) at the center of S-band region. The 1064 nm pump is used to provide both ground-state and excited state absorptions for amplification in the S-band region. The theoretical result is in agreement with the published experimental result.  相似文献   
96.
Abstract

A simple and sensitive spectrophotometric method is described for the determination of buclizine hydrochloride in bulk and tablets form. The method is based on the formation of charge-transfer complex between buclizine, as n-donor, and iodine, as Δ acceptor, which measured spectrophotometrically at 295 and 355 nm. A Job's plot indicated a 1:1 complex between the drug and iodine and Beer's law was obeyed in a concentration range of 4–30 μg ml?1. A more detailed investigation of the complex was made with respect to its association constant and the free energy change. The method is simple and sensitive and has been applied successfully to the analysis of laboratory-made tablets without any interference from the tablet excipients. To validate the method, the results obtained were compared statistically with a newly developed uv-derivative spectrophotometric method. The charge-transfer method was favored due to its higher sensitivity, cheap coast and available equipments.  相似文献   
97.
New guest dye cations within the channel cavities of supramolecular hosts are studied. The guest organic dyes are intercalated in the supramolecular hosts by a coprecipitation reaction to give new dye‐sensitizer coordination polymers. The absorption spectra for the dye molecules within the supramolecular hosts show intense bands in the region from 500 to 700 nm due to the presence of the dyes within the parallel channels in the monomeric forms. The properties of the resulting colored polymers were investigated by IR, UV–vis, fluorescence spectra and X‐ray powder diffraction, indicating the excitation energy transfer from neutral red or pyronine as donors to methylene blue or thionine as acceptors within a supramolecular system filled with a mixture of both dyes. The wide‐ranging tenability of these highly organized materials offers fascinating new possibilities for exploring excitation energy transfer phenomena, and challenges for developing new photonic devices. Copyright © 2005 John Wiley & Sons, Ltd.  相似文献   
98.
A series of fused and spiro pyrazolones, isoxazolines, pyrimidines, β‐lactams, and thiazolidinones incorporating 4‐amino‐2‐methyl‐5,10‐dioxo‐1,5,10,11‐tetrahydrobenz[g]quinoline 3‐carbonitrile 1 and 4‐amino‐2‐methyl‐5,6,11‐trioxo‐1,4,4a,5,6,11,12,12a‐octahydro‐1,12‐diazanaphthacene 3‐carbonitrile 2. 7,8a‐c, 15,16a‐c, 19,20a‐d, 21,22a‐d , have been synthesised by cyclocondensation addition reaction and cycloaddition reaction of hydrazines, hydroxylamine, urea, thiourea, monochloroacetyl chloride and mercaptoacetic acid with the synthesised 15,16a‐c and 17,18a‐c .  相似文献   
99.
Reactions of 2,5‐dibromothiophene, 1 , with [Pd2(dba)3]?dba [Pd(dba)2; dba = dibenzylideneacetone] in the presence of N‐donor ligands such as 2,2′‐bipyridine (bpy) and 4,4′‐di‐tert‐butyl‐2,2′‐bipyridine (dtbbpy) give arylpalladium complexes of cis‐[2‐(5‐BrC4H2S)PdBrL2], 2a, b [L2 = bpy ( 2a ), L2 = dtbbpy ( 2b )], and cis‐cis‐L2PdBr[2,5‐(C4H2S‐)PdBr(L2)], 3a, b [L2 = bpy ( 3a ), L2 = dtbbpy ( 3b )]. Treatment of cis complexes 2a, b and 3a, b with CO causes the insertion of CO into the Pd? C bond to give the aroyl derivatives of palladium complexes of cis‐[2‐(5‐BrC4H2S)COPdBrL2], 4a, b [L2 = bpy ( 4a ), L2 = dtbbpy ( 4b )], and cis‐cis‐[(L2)(CO)BrPdC4H2S‐PdBr(CO)(L2)], 5a, b [L2 = bpy ( 5a ) and L2 = dtbbpy ( 5b )], respectively. Treating complexes 2a, b with 1 mole equivalent of isocyanide XyNC (Xy = 2,6‐dimethylphenyl) gave iminoacyl complexes cis‐[2‐(5‐BrC4H2S)C?NXyPdBrL2], 6a, b [L2 = bpy ( 6a ), L2 = dtbbpy ( 6b )], and a 3‐fold excess of isocyanide XyNC (Xy = 2,6‐dimethylphenyl) gave triiminoacyl complexes [2‐(5‐BrC4H2S)(C?NXy)3 PdBr], 7 . Cyclization reactions of 6a, b with 3 mole equivalents of isocyanide XyNC (Xy = 2,6‐dimethylphenyl) or cyclization reaction of 7 with 1 mole equivalent of isocyanide XyNC (Xy = 2,6‐dimethylphenyl) both gave tetraiminoacyl complexes of [2‐(5‐BrC4H2S)(C?NXy)4PdBr], 8 , which was also obtained by the reaction of 1 or 2a, b with a 4‐fold excess of isocyanide XyNC with or without add Pd(dba)2. Similarly, complexes 3a and b were also reacted with 2 mole equivalents of isocyanide XyNC (Xy = 2,6‐dimethylphenyl) to give iminoacyl complexes cis‐cis‐[(L2)(CNXy)BrPdC4H2S‐PdBr(CNXy)(L2)], 10a, b [L2 = bpy ( 10a ), L2 = dtbbpy ( 10b )] and an 8‐fold excess of isocyanide XyNC (Xy = 2,6‐dimethylphenyl) afforded tetraiminoacyl complexes of [2,5‐(C4H2S)(C?NXy)8Pd2Br2], 11 . Complexes 2a, b and 3a, b reacted with TlOTf [(TfO = CF3SO3)] in CH2Cl2 to give 9a, b and 12a, b , respectively, in a moderate yield. Copyright © 2007 John Wiley & Sons, Ltd.  相似文献   
100.
The behaviour of 3,5-diamino-4-phenylazopyrazole toward a variety of reagents is reported. Several new 3,5-diaminopyrazole derivatives as well as amino derivatives of fused pyrazoles have been prepared.
Untersuchungen an 3,5-Diaminopyrazol-Derivaten
Zusammenfassung Es wird über das Verhalten von 3,5-Diamino-4-phenylazopyrazol gegenüber verschiedenen Agentien berichtet. Es wurden sowohl einige neue 3,5-Diaminooyrazol-Derivate als auch einige Aminoderivate von kondensierten Pyrazolen dargestellt.
  相似文献   
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