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Öğe Comparison of classic and microwave-assisted synthesis of benzo-thio crown ethers, and investigation of their ion pair extractions(Elsevier Science Bv, 2017) Calisir, Umit; Cicek, BakiMacrocyclic benzo-thio crown ethers and benzo-oxo crown ethers were prepared using an esterification ring closing method. These compounds were synthesised using 2,2'-dithiodibenzoyl chloride, and various glycols and dithiols, in the presence of pyridine base under a nitrogen atmosphere in chloroform. All reactions were performed under reflux condition with conventional heating and microwave (MW) irradiation. The synthesised macrocycles were characterised by FT-IR, H-1 NMR, C-13 NMR, LC-MS, and elemental analysis methods. Extraction studies have been performed on these original macrocycles using liquid-liquid ion-pair extraction with Li+, Na+, K+, Ni2+, Ca2+, Mg2+, Zn2+, Fe2+,Fe3+, Co3+, Pb2+, Cr3+, Ag+, and Cd2+.The KD, ext.%, AG and log KExt values were also calculated. While (U1-U7) ligands exhibits selectivity for Zn2+, Ag+, Ca2+, Pb2+, Fe3+, Cr3+, Co2+, Mg2+, Cd2+, and Ni2+ metal salts, they showed no selectivity for Li+, K+ and Na+ metal salts. Furthermore, Fe(3+)is the most selective cation for all ligands for competitive extraction. We also observed that microwave heating can have certain benefits over conventional ovens: reaction rate acceleration, milder reaction conditions, higher chemical yield, and lower energy usage. These ligands could be used as metal sensors, enzyme inhibitors, antimicrobial/antifungal agents, and in biological applications. (C) 2017 Elsevier B.V. All rights reserved.Öğe Comparison of Microwave-assisted Synthesis and Steglich Thioesterification for the Modification of Nanotubes(Bentham Science Publ Ltd, 2025) Aslan, Mehmet; Calisir, Umit; Cicek, BakiOrgano-modified carbon nanotubes have recently gained the interest of many research groups. The potential for applying a new generation of organo-modified carbon nanotubes in many technological fields reveals the importance of covalent modifications on nanotubes. In this study, using the microwave synthesis method, multi-walled carbon nanotube (MWCNT) thiophenol derivatives were obtained with a thioesterification reaction. For this purpose, MWCNT-COOH was obtained from MWCNT by oxidation, and MWCNT-COCl was synthesized from MWCNT-COOH. The MWCNT-CO-S-(ortho/meta/para-methyl/methoxy-phenyl) (MA1-MA6) compounds were synthesized through both microwave synthesis methods starting with MWCNT-COCl and Steglich ester reaction of MWCNT-COOH. Products were characterized using Fourier Transform-Infrared Spectroscopy (FTIR), Nuclear Magnetic Resonance (NMR), Thermogravimetric Analysis (TGA), and Transmission Electron Spectroscopy (TEM) methods. Furthermore, step numbers, reaction times, and temperatures of obtained molecules, MA1-MA6, were compared. Steglich esterification was found to be the most effective technique for creating these compounds. The photoluminescent characteristics of MWCNT, MWCNT-COOH, and MA1-MA6 compounds were examined. The intensity of the photoluminescence (PL) was found to vary with the location of the functional group. It was detected that the MA2 compound had the highest photoluminescence intensity (6.9x102 a.u.), while the MA1 compound had the second-highest photoluminescence intensity (6.9x102 a.u.). MA1 and MA2 were radiated at low wavelengths of 475-490 nm with high PL values. Possible transitions were n ->pi* transitions, with high PL values obtained because of the oxygen atom in the methoxy group. It is expected that these materials will find use in imaging devices operating at high temperatures, particularly because structures containing methoxy groups exhibit favourable photoluminescence properties.Öğe Investigation of in vitro and in silico effects of some novel carbazole Schiff bases on human carbonic anhydrase isoforms I and II(Taylor & Francis Inc, 2022) Camadan, Yasemin; Cicek, Baki; Adem, Sevki; Calisir, Umit; Akkemik, EbruCarbonic anhydrases (CAs, EC4.2.1.1) are metalloenzymes that catalyse reversible hydration reaction of carbon dioxide to bicarbonate and protons. In recent years, there has been a great interest in inhibitors/activators of carbonic anhydrase isoenzymes. Therefore, we investigated the effects of four different carbazole Schiff base derivatives, which are believed to have a potential to be used as a drug, on human carbonic anhydrase (hCA) isoenzymes I and II under in vitro conditions. The IC50 values of carbazole Schiff base derivatives were found to be in the range of 32.09-151.2 mu M for hCA isoenzyme I and 21.82-40.54 mu M for hCA isoenzyme II. Among all compounds, (E)-3-(((9-Octyl-9H-carbazole-3-yl)imino)methyl)benzene-1,2-diol (C3) had the strongest inhibitory effect on hCA isoenzyme II. It was determined that 2,3,4-trimethoxy and 4-hydroxy phenyl containing carbazole compounds have selective inhibition against hCA II isoenzyme. Docking studies were performed against hCA I and II receptors using induced-fit docking method. The compounds had affinity scores varying from -7.74 +/- 0.27 to -6.27 +/- 0.07 kcal/mol for hCA I and from -8.04 +/- 0.17 to -7.27 +/- 0.18 kcal/mol for hCA II. Communicated by Ramaswamy H. SarmaÖğe Microwave-assisted cross-coupling synthesis of aryl functionalized MWCNTs and investigation of hydrogen storage properties(Taylor & Francis Inc, 2021) Calisir, Umit; Cicek, Baki; Dogan, MehmetIn recent years, nanostructures have attracted the attention of many scientists due to their unique properties. Many properties of nanostructures can be improved by changing the surface. For this purpose, multi-walled carbon nanotubes (MWCNTs) were covalently modified using Suzuki-cross coupling reactions with microwave-assisted synthesis. First, the MWCNTs were brominated. Aryl functionalized MWCNTs were synthesized from the reaction of brominated MWCNTs with aryl boronic acid derivatives in the presence of palladium catalyst. Synthesized compounds were characterized by the techniques of Fourier-Transform Infrared Spectroscopy, Nuclear Magnetic Resonance, Thermogravimetric Analysis and Transmission Electron Microscopy. The hydrogen storage properties of the synthetic compounds were determined. The example with the highest hydrogen storage capacity was N2 and its hydrogen storage capacity was determined as 0.45 wt%. The hydrogen storage capacity of functionalized MWCNTs was consistent with the results of carbon nanomaterials in the literature.Öğe Microwave-Assisted Synthesis of Aromatic Thiadiazol Crown Ethers and Determination of Complexation Properties with Metal Ions by Application of Job?s Plot Method to Conductometry(Wiley-V C H Verlag Gmbh, 2022) Canbolat, Musa; Calisir, Umit; Cicek, BakiThe microwave-assisted synthesis technique, one of the pioneers of green chemistry, was used to synthesize aromatic thiadiazole crown ethers in this study. Thiadiazole crown ethers were synthesized by the cyclization reaction of 2-amino-5-mercapto-1,3,4-thiadiazole and mono-di-tri-tetra ethylene glycol dichloride compounds using the S(N)2 reaction mechanism in acetonitrile solvent and the presence of cesium carbonate base. FT-IR, H-1-NMR, C-13-NMR, LC-MS/MS spectroscopic techniques, and elemental analysis were used to characterize the synthesized compounds after purification. Furthermore, the conductivity behaviour of the synthesized compounds against metal salts (NaCl, KCl, MgCl2, CaCl2, ZnCl2, FeSO4, AgNO3, CoCl2) was determined using Job ' s Plot technique, which was adapted to conductometry. Interactions between ligands and ions were investigated. According to conductometric data, thiadiazole crown ethers showed significant complexations; M1 and M4 with Ca2+, M2 with Fe2+, and M3 with Co2+ ions.Öğe Synthesis and optical characterization of novel carbazole Schiff bases(Elsevier Science Bv, 2018) Cicek, Baki; Calisir, Umit; Tavasli, Mustafa; Tulek, Remziye; Teke, AliIn this study, newly substituted carbazole derivatives of S1; (Z)-4-((9-isobutyl-9H-carbazol-3-ylimino) methyl)phenol, S2; (Z)-9-butyl- N-(2,3,4-trimethoxybenzylidine)-9H-carbazol-3-amine, S3; (Z)-4-((9-octyl-9H-carbazol-3-ylimino)methyl)benzene-1,2-diol and S4; (Z)-3-((9-octyl-9H-carbazol-3-ylimino) methyl)benzene-1,2-diol compounds are synthesized by using condensation reaction between carbazole amines and aromatic aldehydes. All synthesized carbazole Schiff bases are purified by crystallizing from chloroform. The structural and optical characterizations of synthesized compounds are investigated by FT-IR (Fourier Transform-Infrared Spectroscopy), H-1 NMR (Proton Nuclear Magnetic Resonance),C-13 NMR (Carbon Nuclear Magnetic Resonance), LC-MS (Liquid Chromatography-Mass Spectrometry) and temperature dependent PL (Photoluminescence) measurements.. The formations of synthesized Schiff bases were confirmed by FF-IR, NMR and microanalysis. Due to stronger pi-conjugation and efficient charge transfer from host material, the broad and complex bands centered at about similar to 2.16 and similar to 1.76 eV are observed in PL spectra for all samples. Their relative intensities depend on functional groups associated with the carbazole. These newly synthesized Schiff bases could be considered as an active emissive layer for organic light emitting diodes. (C) 2017 Elsevier B.V. All rights reserved.Öğe Synthesis of thiol-glycol-functionalized carbon nanotubes and characterization with FTIR, TEM, TGA, and NMR technics(Springer International Publishing Ag, 2020) Calisir, Umit; Cicek, BakiCarbon nanotube is one of the important topics of interest in the nanotechnology science. Many scientists have been interested in surface-modified nanotubes for decades. In this study, multi-walled carbon nanotubes (MWCNTs) were functionalized with polyethylene glycol and dithiols in esterification reactions. The MWNTs were first carboxylate-functionalized. The carboxylated MWCNTs were acyl chlorite substituted. The functionalized MWNTs were used as the precursor to esterification of polyethylene glycols and thiols. The reactions were performed catalysts or non-catalysts, solvent-free and solvent media, using microwave-assisted and classical methods. The synthesized compounds were characterized by FTIR, TGA, TEM and NMR techniques. We investigate the advantage of microwave synthesis method in terms of time and solvent in Green Chemistry. The obtained compounds exhibit very interesting results in their complexes with metals due to containing free hydroxyl and thiol groups.Öğe Synthesis, activatory effects, molecular docking and ADME studies as rabbit muscle pyruvate kinase activators of ureido phenyl substituted 1,4-dihydropyridine derivatives(Springer, 2024) Kaya, Mustafa Oguzhan; Demirci, Tuna; Calisir, Umit; Ozdemir, Oguzhan; Kaya, Yesim; Arslan, MustafaIn this study, the activation of pyruvate kinase enzyme in vitro via different urea substituents in the para position as functional groups of 1,4-dihydropyridine derivatives synthesized by Hantzsch reaction method was investigated. Elemental analysis, 1H-NMR, 13C-NMR and FT-IR spectroscopy were used to identify the ureido phenyl substituted 1,4-dihydropyridine derivatives. Virtual screening based on molecular docking supported the results of possible in vitro pyruvate kinase (PK) activators among the synthesized substances. The results showed that all compounds successfully activated PK. The strongest activator effect was shown by ethyl-4-(4-(4-(3-(3-methoxyphenyl)thioureido)phenyl)-2,7,7-trimethyl-5-oxo-1,4,5,6,7,7,8-hexahydroquinolin-3 (7) with an AC50 value of 87.70 mu M. In molecular docking studies, full compatibility (- 3016.93 FF), binding affinities (Delta G = - 8.58 kcal/mol), LUMO-HOMO energy gap (Delta E = 7.85 eV) in Density functional theory (DFT) studies and drug similarity score of the compounds were found to be 0.69. These results shed light on the therapeutic potential of the produced compounds to treat PK-related diseases.Öğe Synthesis, characterizations of aryl-substituted dithiodibenzothioate derivatives, and investigating their anti-Alzheimer's properties(Taylor & Francis Inc, 2023) Calisir, Umit; Camadan, Yasemin; Cicek, Baki; Akkemik, Ebru; Eyupoglu, Volkan; Adem, SevkiThe main objective of the present study was to synthesize potential inhibitor/activators of AChE and hCA I-II enzymes, which are thought to be directly related to Alzheimer's disease. Dithiodibenzothioate compounds were synthesized by thioesterification. Six different thiolate compounds produced were characterized by H-1-, C-13-NMR, FT-IR, LC-MS/MS methods. HOMO-LUMO calculations and electronic properties of all synthesized compounds were comprehensively illuminated with a semi-empirical molecular orbital (SEMO) package for organic and inorganic systems using Austin Model 1 (AM1)-Hamiltonian as implemented in the VAMP module of Materials Studio. In addition, the inhibition effects of these compounds for AChE and hCA I-II in vitro conditions were investigated. It was revealed that TE-1, TE-2, TE-3, TE-4, TE-5, and TE-6 compounds inhibited the AChE under in vitro conditions. TE-1 compound activated the enzyme hCA I while TE-2, TE-3 TE-4 compounds inhibited it. TE-5 and TE-6, on the other hand, did not exhibit a regular inhibition profile. Similarly, TE-1 activated the hCA II enzyme whereas TE-2, TE-3, TE-4, and TE-5 compounds inhibited it. TE-6 compound did not have a consistent inhibition profile for hCA II. Docking studies were performed with the compounds against AChE and hCA I-II receptors using induced-fit docking method. Molecular Dynamics (MD) simulations for best effective three protein-ligand couple were conducted to explore the binding affinity of the considered compounds in semi-real in-silico conditions. Along with the MD results, TE-1-based protein complexes were found more stable than TE-5. Based on these studies, TE-1 compound could be considered as a potential drug candidate for AD. Communicated by Ramaswamy H. SarmaÖğe Synthesis, inhibition effects, molecular docking and theoretical studies as Paraoxonase 1 (PON1) inhibitors of novel 1,4-dihydropyridine substituted sulfonamide derivatives(Springer Birkhauser, 2023) Kaya, Mustafa Oguzhan; Demirci, Tuna; Ozdemir, Oguzhan; Calisir, Umit; Sonmez, Fatih; Arslan, MustafaThe novel sulfonamide substitute 1,4-dihydropyridine derivatives were synthesized by the method of Hantzsch reaction. They have been characterized by FT-IR spectroscopy, H-1-NMR, C-13-NMR, and elemental analysis. PON1 which is an antioxidant enzyme has important functions in cardiovascular systems. The enzyme has been purified using a two-step method such as ammonium sulfate precipitation and sepharose-4B-l-tyrosine-9-aminophenanthrene hydrophobic interaction chromatography. The results demonstrated that all the synthesized compounds inhibited PON1 enzyme. The best inhibition effect was observed in compound (1) for PON1 enzyme (IC50: 8.04 mu M, K-i: 5.43 mu M). The free radical scavenging for PON1 was discovered as 20.16 mg/mL, while drug score value was reported as 0.13 for compound (1). Furthermore, the lowest binding energy (-1.31 kcal/mol) determined by molecular docking for PON1 enzyme and the lowest LUMO-HOMO gap ( increment E = 3.12 eV) were calculated for compound (1).Öğe The determination of the carbonic anhydrases activators in vitro effect of mixed donor crown ethers(Wiley, 2018) Akkemik, Ebru; Cicek, Baki; Camadan, Yasemin; Calisir, Umit; Onbasioglu, ZekaiCarbonic anhydrases (CAs) play an important function in various physiological and pathological processes. Therefore, many researchers work in this field in order to design and synthesize new drugs. Both inhibitors and activators of CAs, which are associated with the diagnosis and treatment of many diseases, are very important. The emergence of the use of CA activators in the treatment of Alzheimer has led many scholars to work on this issue. In this study, CA activators and inhibitors are determined. The crown ethers compounds (1, 2, 3, 6, 7, 8, and 9) were found to cause activation on enzyme activities of hCA I and II. The AC(50) values on hCA I and II of the compounds are in the range of 4.6565-374.979M. The 4 (IC50; 1.301 and 3.215M for hCA I and II) and 5 (IC50; 73.96 and 378.5M for hCA I and II) compounds were found to cause inhibition on enzyme activities of hCA I and II.
