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Öğe A comprehensive MCDM assessment for economic data: success analysis of maximum normalization, CODAS, and fuzzy approaches(Springer, 2024) Baydas, Mahmut; Yilmaz, Mustafa; Jovic, Zeljko; Stevic, Zeljko; Ozuyar, Sevilay Ece Gumus; Ozcil, AbdullahThe approach of evaluating the final scores of multi-criteria decision-making (MCDM) methods according to the strength of association with real-life rankings is interesting for comparing MCDM methods. This approach has recently been applied mostly to financial data. In these studies, where it is emphasized that some methods show more stable success, it would be useful to see the results that will emerge by testing the approach on different data structures more comprehensively. Moreover, not only the final MCDM results but also the performance of normalization techniques and data types (fuzzy or crisp), which are components of MCDM, can be compared using the same approach. These components also have the potential to affect MCDM results directly. In this direction, in our study, the economic performances of G-20 (Group of 20) countries, which have different data structures, were calculated over ten different periodic decision matrices. Ten different crisp-based MCDM methods (COPRAS, CODAS, MOORA, TOPSIS, MABAC, VIKOR (S, R, Q), FUCA, and ELECTRE III) with different capabilities were used to better visualize the big picture. The relationships between two different real-life reference anchors and MCDM methods were used as a basis for comparison. The CODAS method develops a high correlation with both anchors in most periods. The most appropriate normalization technique for CODAS was identified using these two anchors. Interestingly, the maximum normalization technique was the most successful among the alternatives (max, min-max, vector, sum, and alternative ranking-based). Moreover, we compared the two main data types by comparing the correlation results of crisp-based and fuzzy-based CODAS. The results were very consistent, and the Maximum normalization-based fuzzy integrated CODAS procedure was proposed to decision-makers to measure the economic performance of the countries.Öğe Phase Solubility Studies of Poorly Soluble Drug Molecules by Using O-Phosphorylated Calixarenes as Drug-Solubilizing Agents(AMER CHEMICAL SOC, 2012) Bayrakci, Mevlut; Ertul, Seref; Yilmaz, MustafaThis study is the first report on the solubilizing effect of O-phosphorylated calix[n]arenes that form complexes with neutral molecules such as nifedipine, niclosamide, and furosemide by host-guest complexation. These complexation studies were carried out by using the phase solubility technique. From the obtained results, it was observed that the solubility of guest molecules such as nifedipine, niclosamide, and furosemide was significantly increased in the presence of host molecules tetrakis-O-(diethoxyphosphoryl)-p-tert-butylcalix[4]arene (1), tetrakis-O-(diethoxyphosphoryl)-calix[4]arene (2), bis-O-(diethoxyphosphoryl)-p-tert-butylcalix[4]arene (3), bis-O-(diethoxyphosphoryl)-calix[4]arene (4), and octakis-O-(diethoxyphosphoryl)-p-tert-butylcalix[8]arene (5). The increase in solubility of drugs by the calixarene host 1 to 5 was most probably due to inclusion complexation between drug molecules and cavities of the calixarene skeleton similar to drug-cyclodextrin complexes.Öğe Removal of Phosphate Anions from Aqueous Solutions by Using Macrocyclic Receptors-Based Polyether, Lactone and Lactam Derivatives(TAYLOR & FRANCIS INC, 2011) Ertul, Seref; Bayrakci, Mevlut; Yilmaz, MustafaIn this study, the phosphate anions extraction efficiency of a series of receptors-based lactones 1a-d, 2, and 3, polyethers 4 and 5, lactam derivatives 6a-b, 7a-b, and 8a-d towards phosphate anion was evaluated by solvent extraction. It was observed that compounds 7a-b exhibited higher affinity toward phosphate ions than the other receptors. The extraction of phosphate anions by these compounds 7a-b indicates that the partially protonated amino groups play the major role for the formation of hydrogen bonds and electrostatic interactions at low pH. Furthermore, the effect of the polyethylene linkage and cavity of crown moieties on anion extraction was investigated. To evaluate the selectivity of receptors 6a-b and 7a-b, we also examined the retention of phosphate anions in the presence of Cl-, [image omitted], and [image omitted] anions at pH 1.5.Öğe Solubilizing effect of the p-phosphonate calix[n]arenes towards poorly soluble drug molecules such as nifedipine, niclosamide and furosemide(SPRINGER, 2012) Bayrakci, Mevlut; Ertul, Seref; Yilmaz, MustafaThis article reports the solubilization of the practically water insoluble drug molecules such as nifedipine, niclosamide and furosemide by guest:host inclusion complexation with p-phosphonates calix[n]arenes as drug soluble agent. This complexation studies were carried out by using the phase solubility technique. From the obtained results, it was observed that the solubility of drug molecules was significantly increased in the presence of calix[n]arene host molecules. The increase in solubility of drugs by the calix[n]arene was most probably due to inclusion complexation between drug molecules and cavities of the calixarene skeleton similar to drug:cyclodextrin complexes.Öğe Synthesis of di-substituted calix[4]arene-based receptors for extraction of chromate and arsenate anions(PERGAMON-ELSEVIER SCIENCE LTD, 2009) Bayrakci, Mevluet; Ertul, Seref; Yilmaz, MustafaThe article describes the synthesis of a family of novel calix[4]arene ionophores, 25,27-bis-(2-aminomethylpyridine-propoxy)-26,28-dihydroxycalix[4]arene (5a), 25,27-bis-(3-aminomethylpyridine-propoxy)-26,28-dihydroxycalix[4]arene (5b) and two chromogenic calix[4]arenes, 5,17-dinitro-25,27-bis-(2-aminomethylpyridine-propoxy)-26,28-dihydroxycalix[4]arene (5c), 5,17-dinitro-25,27-bis-(3-aminomethylpyridine-propoxy)-26,28-dihydroxycalix[4]arene (5d) bearing pyridinium units. In the synthesis, the upper and lower rims of p-tert-butylcalix[4]arene were modified in order to acquire binding sites for the recognition of arsenate and dichromate anions. It has been observed that protonated alkylammonium forms of the ionophores showed high affinity toward dichromate and arsenate anions. (C) 2009 Elsevier Ltd. All rights reserved.Öğe Synthesis of new water-soluble phosphonate calixazacrowns and their use as drug solubilizing agents(SPRINGER, 2012) Bayrakci, Mevlut; Ertul, Seref; Yilmaz, MustafaThis study presents the selective chloromethylation of calix[4](aza)crown ethers 2a-c, using chloromethyl n-octyl ether and SnCl4 in chloroform at room temperature in good yield for the first time. Chloromethylated products 2a-c are used as key intermediates to synthesize new water-soluble p-phosphonato calix[4](aza)crown ethers 5a-c. Liquid-liquid phase extraction and phase solubility studies with poor water soluble drug molecules such as nifedipine, niclosamide and furosemide are performed to evaluate their binding properties. Among the studied drugs, furosemide was the most effectively dissolved drug by p-phosphonato calix[4](aza)crown ethers 5a-c in water.Öğe Transportation of Poorly Soluble Drug Molecules from the Organic Phase to the Aqueous Phase by Using Phosphorylated Calixarenes(AMER CHEMICAL SOC, 2011) Bayrakci, Mevlut; Ertul, Seref; Yilmaz, MustafaThis study is the first report on the extraction of poorly soluble drug molecules such as nifedipine, niclosamide, and furosemide from the organic phase to the aqueous phase by water-soluble p-phosphonate calix[n]arene receptors via a liquid-liquid phase extraction process. These water-soluble calixarene derivatives were easily obtained from the reaction between their corresponding chloromethylated derivatives and trimethyl phosphite. From the liquid-liquid phase extraction studies, it was observed that the size of the p-phosphonate calix[n]arenes changed the extraction percentage of selected drug molecules.Öğe Upper rim-functionalized calix[4]arene-based L-proline as organocatalyst for direct asymmetric aldol reactions in water and organic media(PERGAMON-ELSEVIER SCIENCE LTD, 2014) Uyanik, Arzu; Bayrakci, Meylut; Eymur, Serkan; Yilmaz, MustafaThe synthesis of upper rim-functionalized calix[4]arene-based L-proline was described, and its catalytic efficiency as organocatalyst for the enantioselective aldol reaction in water was investigated. The results showed that the nature of the hydrophobic cavity of calixarene is critical for catalytic activity in water. The products of the reaction between various ketones and aldehydes with anti-configuration were obtained in high yields (up to 94%) with high diastereo- (up to 95:5 dr) and enantioselectivities (up to 80% ee). (C) 2014 Elsevier Ltd. All rights reserved.
