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151.
Ali İhsan Öztürk Fatih Aslan Ökkeş Yılmaz Mehmet Alğın Mustafa Arslan H. İbrahim Mutlu 《Phosphorus, sulfur, and silicon and the related elements》2013,188(5):585-595
Abstract Hexa(4-bromo-2-formyl-phenoxy)cyclotriphosphazene (2) and hexa(4-chloro-2- formyl-phenoxy)cyclotriphosphazene (3) were obtained from the reactions of hexachloro- cyclotriphosphazene (1) with 5-bromosalicylaldehyde and 5-chlorosalicylaldehyde in the presence of (C2H5)3N and K2CO3 at room temperature, respectively. The new two organocyclotriphosphazenes bearing formyl groups were reacted with 4-cyano aniline, 2-phenyl aniline, 4-aceto aniline, 5-chloro-2-hydroxy aniline, 2-hydroxy aniline, 4-hydroxy aniline, 2-(4-morpholino)ethyl amine, 4-carboxy aniline, 4-carbomoyl aniline, 2-mercapto aniline, and 5-amino isoquonoline to prepare cyclotriphosphazene derivatives containing a Schiff base at room temperature. However, fully phenoxy-substituted cyclotriphosphazenes containing a Schiff base were isolated from the reactions of the compound 2 and 3 with 5-chloro-2-hydroxy aniline, 2-hydroxy aniline, 4-hydroxy aniline, and 2-(4-morpholino)ethyl amine. The structures of the synthesized compounds were characterized by elemental analysis, IR, and NMR (1H, 13C, 31P) spectroscopy. According to the results of the analysis, all synthesized compounds were found to be fully substituted organocyclotriphosphazenes, such as hexa[4-bromo-2-(5-chloro-2-hydroxy-pheyliminomethyl)phenoxy]cyclotriphosphaze (2a). All cyclotriphosphazene derivatives synthesized gave fluorescence emission peaks in range between 300 nm and 410 nm. 相似文献
152.
153.
Cemil İbiş Nihal Yılmaz 《Phosphorus, sulfur, and silicon and the related elements》2013,188(12):2543-2548
Compounds 3a–c, 4a, b, 5a–c, and 6a, c were obtained from the reactions of perchlorobutadiene (1) with 1,4-butanedithiol (2a), 1,5-pentanethiol (2b), and 2.2′-(ethlene-dioxyl)diethanethiol (2c) in ethanol in the presence of sodium hydroxide. Compounds 7a, b were obtained from the reactions of thioethers 3a, b with m-chlorperbenzoic acid in CHCl 3 . 相似文献
154.
Selin Çelebi Esin İbibikcan Senem Kiralp Kayahan Başak Yiĝitsoy Levent Toppare 《高分子科学杂志,A辑:纯化学与应用化学》2013,50(8):739-744
Immobilization of invertase in conducting copolymer matrix of 2,5-di(thiophen-2-yl)-1-p-tolyl-1H-pyrrole with pyrrole (poly(DDTP-co-Py)) was achieved via electrochemical polymerization. Kinetic parameters, Michaelis-Menten constant, Km and the maximum reaction rate, Vmax were investigated. Operational stability and temperature optimization of the enzyme electrodes were also examined. Immobilized invertase reveals maximum activity at 50°C and; pH 8 and pH 4 for two copolymer matrices. Although the same two monomers are utilized for the copolymer synthesis, the way the copolymer is produced results in quite different responses in terms of enzyme activity, optimum pH and kinetic parameters. Excellent operational stability of the enzyme electrodes enables their repetitive use in the determination of invert sugar. 相似文献
155.
In this study the binary and ternary complexes of copper(II) with substituted 1,10-phenanthrolines [s-phen: 1,10-phenanthroline (phen), 4,7-dimethyl-1,10-phenanthroline (dmphen) and 5-nitro-1,10-phenanthroline (nphen)] and l-amino acids [aa: l-phenylalanine (phe), l-tyrosine (tyr) and l-tryptophan (trp)] have been investigated using potentiometric methods in 0.1 mol·L?1 KCl aqueous ionic media at 298.2 K. The protonation constants of the ligands and the stability constants of the binary and ternary complexes of Cu(II) with the ligands were calculated from the potentiometric data using the “BEST” software package. It was inferred that the aromatic 1,10-phenanthrolines act as a primary ligand in the ternary complexes, while the oxygen and nitrogen donor-containing amino acids are secondary ligands. The observed values of Δlog10 K indicate that the ternary complexes are more stable than the binary ones, suggesting no interaction takes place between the ligands in the ternary complexes. The magnitudes of the measured stability constants of all of the ternary complexes are in the order [Cu(s-phen)(trp)]+ > [Cu(s-phen)(tyr)]+ > [Cu(s-phen)(phe)]+, which is identical to the sequence found for the binary complexes of Cu(II) with the amino acids. When the substituted 1,10-phenanthroline is changed, the stability constants of the ternary complexes decrease in the following order: [Cu(dmphen)(aa)]+ > [Cu(phen)(aa)]+ > [Cu(nphen)(aa)]+. 相似文献
156.
The [3,3′(4H,4′H)‐bi‐2H‐1,3‐oxazine]‐4,4′‐diones 3a – 3i were obtained by [2+4] cycloaddition reactions of furan‐2,3‐diones 1a – 1c with aromatic aldazines 2a – 2d (Scheme 1). So, new derivatives of bi‐2H‐1,3‐oxazines and their hydrolysis products, 3,5‐diaryl‐1H‐pyrazoles 4a – 4c (Scheme 3), which are potential biologically active compounds, were synthesized for the first time. 相似文献
157.
158.
Necmettin Yildirim Mehmet Çiftçi Ö. İrfan Küfrevioğlu 《Journal of mathematical chemistry》2002,31(1):121-130
This paper describes a general methodology to handle closed multi enzyme systems using mixture of symbolic (which depends on the Gröbner Basis technique) and numerical computation methods. The applicability of the proposed method has been examined for the closed three-enzyme system of rabbit heart creatine kinase (EC 2.7.3.2), yeast hexokinase (EC 2.7.1.1) and human erythrocyte glucose 6-phosphate dehydrogenase (EC 1.1.1.49) using experimental data. 相似文献
159.
Hatice Gül İnce İlarslan Gülen Başcanbaz-Tunca 《Mediterranean Journal of Mathematics》2016,13(5):2577-2592
In this paper, we deal with Bernstein-type operators defined by Cárdenas-Morales et al. as \({B_{n}(f \circ \tau^{-1}) \circ \tau}\), where \({B_{n}}\) is the nth Bernstein polynomial (Comput Math Appl 62(1):158–163, 2011). Assuming that \({\tau}\) and f are absolutely continuous functions on \({[0, 1]}\) and inf \({\tau ^{\prime} (x) \geq m > 0}\) as well as \({\tau (0) = 0}\) and \({\tau (1) = 1,}\) we study the convergence of Bernstein-type operators to f in variation seminorm. Moreover, we give a Voronovskaja-type formula and a Jackson-type estimate in the sense of Bardaro et al. (Analysis 23:299–340, 2003). 相似文献
160.
1,3-二烷基咪唑啉/Pd催化卤代芳烃的Heck和Suzuki反应 总被引:1,自引:0,他引:1
Sedat YASAR lsmail OEZDEMiR Bekir CETINKAYA 《催化学报》2008,29(2):185-190
合成并表征了一种新型的有空间需求的N-杂环卡宾前驱体 1,3-二烷基咪唑啉盐. 这些咪唑啉盐与乙酸钯结合形成的高活性催化剂,可在温和条件下催化氯代和溴代芳烃的He ck和Suzuki交叉偶联反应. 相似文献