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61.
Hakan Gker Süreyya
lgen Rahmiye Ertand HÜLya Akgün Süheyla
zbey Engin Kendi GÜL Topu 《Journal of heterocyclic chemistry》1995,32(6):1767-1773
The title compounds, 1,2-dialkyl-benzimidazole-5(6)-carboxylic acids 34–45 were prepared at four steps; 1) preparation of mono amide derivatives 1–11 by the reaction of methyl 3,4-diaminobenzoate and substituted phenyl or phenoxyacetic acid chlorides; 2) preparation of the methyl benzimidazolecarboxyl-ates 12–22 , with zinc chloride and dry hydrogen chloride gas; 3) alkaline hydrolysis of the esters 23–33 ; and 4) substitution of the imidazole ring with benzyl or p-fluorobenzyl bromide, in alkali medium. 2-Aryl-benzimidazole-5(6)-carboxylic acids 50–53 were prepared via the oxidative condensation of 3,4-diaminobenzoic acid and aromatic aldehydes with cupric ion. 相似文献
62.
Sıla Çetinkaya Burcu B Keskin Halit Üster 《The Journal of the Operational Research Society》2014,65(9):1371-1379
We consider a two-stage distribution system, where the first stage consists of potential distribution centres (DCs) and the second stage consists of geographically dispersed existing retailers. Our goal is to determine the set of open DCs and assignment of open DCs to retailers simultaneously with inventory decisions of retailers. In addition to the DC-specific fixed facility location costs, we explicitly model the inventory replenishment and holding costs at the retailers and truckload transportation costs between the DCs and the retailers. The transportation costs are subject to truck/cargo capacity, leading to an integrated location-inventory problem with explicit cargo costs. We develop a mixed-integer nonlinear model and analyse its structural properties leading to exact expressions for the so-called implied facility assignment costs and imputed per-unit per-mile transportation costs. These expressions analytically demonstrate the interplay between strategic location and tactical inventory/transportation decisions in terms of resulting operational costs. Although both the theory and practice of integrated logistics have recognized the fact that strategic and tactical decisions are interrelated, to the best of our knowledge, our paper is the first to offer closed-form results demonstrating the relationship explicitly. We propose an efficient solution approach utilizing the implied facility assignment costs and we demonstrate that significant savings are realizable when the inventory decisions and cargo costs are modelled explicitly for facility location purposes. 相似文献
63.
We consider the multi-period location planning problem of emergency medical service (EMS) stations. Our objective is to maximize the total population serviced by two distinct stations within two different response time limits over a multi-period planning horizon. Our aim is to provide a backup station in case no ambulance is available in the closer station and to develop a strategic plan that spans multiple periods. In order to solve this problem, we propose a Tabu Search approach. We demonstrate the effectiveness of the proposed approach on randomly generated data. We also implement our approach to the case of Istanbul to determine the locations of EMS stations in the metropolitan area. 相似文献
64.
65.
Decolorization Potential of Some Reactive Dyes with Crude Laccase and Laccase-Mediated System 总被引:2,自引:0,他引:2
Samet Şaşmaz Serap Gedikli Pınar Aytar Gökhan Güngörmedi Ahmet Çabuk Evrim Hür Arzu Ünal Nazif Kolankaya 《Applied biochemistry and biotechnology》2011,163(3):346-361
In this study, decolorization of dyestuffs, such as Reactive Red 198, Rem Blue RR, Dylon Navy 17, Rem Red RR, and Rem Yellow
RR was studied using laccase and laccase-mediated system. The laccases are known to have an important potential for remediation
of pollutants. Among these dyestuffs, decolorization of Rem Blue RR and Dylon Navy 17 was performed with crude laccase under
optimized conditions. Vanillin was selected as laccase mediator after screening six different compounds with Rem Yellow RR,
Reactive Red 198, and Rem Red RR as substrates. However, Rem Yellow RR was not decolorized by either laccase or laccase-mediated
system. It is observed that the culture supernatant contained high laccase activity after treatment with catalase that was
responsible for the decolorization. Besides, culture supernatant with high laccase activity as enzyme source was treated with
catalase; in this way, the hypothesis that laccase was the enzyme responsible for decolorization was supported. The Rem Blue
RR was decolorized with 64.84% under the optimum conditions and Dylon Navy 17 with 75.43% with crude laccase. However, using
the laccase and vanillin, the decolorization of Reactive Red 198 and Rem Red RR was found to be 62% and 68%, respectively.
Our study demonstrated that the decolorization abilities of laccase and/or laccase mediator systems were based on the types
of mediator, the dye structure, and the standard experimental conditions. Also, the electrochemical behaviors of some samples
were studied. The redox potentials of these samples were determined using cyclic voltammetry on glassy carbon electrode in
phosphate buffer (pH 6) solution. 相似文献
66.
Lengyel L Gyóllai V Nagy T Dormán G Terleczky P Háda V Nógrádi K Sebok F Urge L Darvas F 《Molecular diversity》2011,15(3):631-638
Aromatic or heteroaromatic ring precursors with 2–3 identical functionalities are often used in sequential derivatization
depending on the reactivity difference or the selective execution of the reaction such as nucleophilic aromatic substitution.
Continuous flow chemistry offers an enhanced parameter space (pressure and temperature) with rapid parameter optimization
that ensures selectivity in many cases. We developed a flow chemistry procedure to carry out a stepwise aromatic nucleophilic
substitution of difluoro-benzenes having an activating group in meta position to the fluorines. The mono-aminated products were obtained in high yield and selectivity in an extremely short reaction
time, while applying higher temperature, longer reaction zone (or time), and employing higher excess of another amine reactant,
the subsequent introduction of the second amino group was also successfully achieved leading to an unsymmetrically substituted
3,5-diamino-benzonitrile library. 相似文献
67.
Hüseyin Ünver Mustafa Yıldız Nazan Ocak Tahsin Nuri Durlu 《Journal of chemical crystallography》2008,38(2):103-108
Abstract Schiff base 3-[(2-morpholinoethylimino)methyl]benzene-1,2-diol has been synthesized from the reaction of 4-(2-aminoethyl)morpholine
with 2,3-dihydroxybenzaldehyde. The title compound has been characterized by elemental analysis, IR, 1H-NMR, 13C-NMR and UV–visible techniques. The structure of the compound also has been examined crystallographically. For the compound
exist as dominant form of enol-imines in both the solutions and solid state. The crystal structure has been solved by direct
methods and refined by full-matrix least squares. The title compound crystallize in the monoclinic space group P21/n with a = 12.085(1), b = 8.256(1), c = 13.650(1) ?, β = 108.56(1)°, V = 1291.1(2) ?3, D
x
= 1.288 g cm−3, respectively (R
1 = 0.0336 and wR
2 = 0.0922 for 2117 reflections [I > 2σ(I)].
Index abstract Intramolecular hydrogen bonding is important on the tautomeric properties and the type of aldehyde plays a vital role of the
enol-imine and keto-amine properties of the Schiff base ligand.
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