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Full-Text Articles in Chemistry
A Theoretical Investigation On The Activation Of Small Molecules By A Disilenide: A Dft Prediction, Cem Burak Yildiz, Akin Azi̇zoğlu
A Theoretical Investigation On The Activation Of Small Molecules By A Disilenide: A Dft Prediction, Cem Burak Yildiz, Akin Azi̇zoğlu
Turkish Journal of Chemistry
Herein, we proposed several mechanistic scenarios for activation of small molecules (NH$_{3}$, CO$_{2}$, CS$_{2}$, H$_{2}$, CH$_{4}$, N$_{2}$, and N$_{2}$O) by a disilicon analogue of a vinyl anion (1H) using density functional theory (DFT) calculations. The DFT results established that all the possible reactions to yield a variety of potential products have an exergonic nature except for the activation of N$_{2}$ with the obtained overall energy of $\Delta $G = 33.6 kcal mol$^{-1}$. Moreover, the highest exergonic character was $\Delta $G = $-$95.8 kcal mol$^{-1}$ for N$_{2}$O. Therefore, the findings reveal that 1H can be considered a suitable candidate for activation …
The Promoted Synthesis Of Minoxidil By Magnetic Nanoparticles Of Cobalt Ferrite (Cofe$_{2}$O$_4$) As A Heterogeneous Reusable Catalyst, Ronak Eisavi, Fateme Ahmadi, Behzad Zeynizadeh, Mehri Kouhkan
The Promoted Synthesis Of Minoxidil By Magnetic Nanoparticles Of Cobalt Ferrite (Cofe$_{2}$O$_4$) As A Heterogeneous Reusable Catalyst, Ronak Eisavi, Fateme Ahmadi, Behzad Zeynizadeh, Mehri Kouhkan
Turkish Journal of Chemistry
Minoxidil (2,4-diamino-6-piperidinopyrimidine 3-oxide) was primarily recognized as a drug for reducing vascular resistance to blood flow. It was later introduced as a more important medicine for topical stimulation of hair growth and baldness reverting as well as treatment of androgenic alopecia through increasing prostaglandin endoperoxide synthesis. In this study, magnetic nanoparticles (MNPs) of spinel ferrites (MFe$_{2}$O$_{4}$, M = Co, Ni, Fe, Cu, and Zn) via solid-state grinding procedure were prepared and then characterized using X-ray diffraction, scanning electron microscopy, transmission electron microscopy, vibrating sample magnetometer, and Fourier transform infrared techniques. The prepared nanoferrites were utilized as efficient and green heterogeneous …
Stability Improvement By Crosslinking Of Previously Immobilized Glucose Oxidase On Carbon Nanotube-Based Bioanode, Tahsi̇n Bahar
Stability Improvement By Crosslinking Of Previously Immobilized Glucose Oxidase On Carbon Nanotube-Based Bioanode, Tahsi̇n Bahar
Turkish Journal of Chemistry
Bioanode stability with glucose oxidase was enhanced significantly by covalent crosslinking without substantial enzymatic activity and affinity loss. Initially, glucose oxidase was immobilized by aldehyde groups on the electrode that was developed using ferrocenecarboxaldehyde, polyethyleneimine, multiwall carbon nanotubes, and carbon cloth for biofuel cell applications. The glucose oxidase half-life was extended by more than 4 times, from 27.2 to 124.7 h, after the electrode was crosslinked. Enzymatic kinetic parameters were determined for the crosslinked enzyme and they were compared to the noncrosslinked immobilized enzyme parameters on the electrode. The apparent substrate affinity of the crosslinked enzyme electrode was decreased (i.e. …
Biodegradability Study Of Polypropylene Fibers Blended With Disposable Recycled Poly(Lactic Acid) Plastic Flakes, Mohammad Ali Tavanaie, Abolfazl Mahmudi Gevari
Biodegradability Study Of Polypropylene Fibers Blended With Disposable Recycled Poly(Lactic Acid) Plastic Flakes, Mohammad Ali Tavanaie, Abolfazl Mahmudi Gevari
Turkish Journal of Chemistry
Polymer blending as an efficient method for blending at least two~polymers is usually used to create new materials with desirable physical properties. This article focuses on the biodegradability evaluation of polypropylene (PP) fibers modified with disposable recycled poly(lactic acid) (r-PLA) plastic flakes. Biodegradable modified PP fibers containing 30% r-PLA were prepared by melt spinning process and evaluated with different methods of biodegradation assays. The soil burial test method, CO$_{2}$ evolution analysis, weight loss, mechanical properties, and average molecular weight measurements and analysis of surface morphological changes were performed for biodegradability evaluation of the modified PP fibers. Surface morphology of the …
Synthesis And Characterization Of Polycaprolactone-Based Segmented Polyurethanes, Aysun Güney, Aysel Kiziltay, Nesri̇n Hasirci, Tuğba Endoğan Tanir
Synthesis And Characterization Of Polycaprolactone-Based Segmented Polyurethanes, Aysun Güney, Aysel Kiziltay, Nesri̇n Hasirci, Tuğba Endoğan Tanir
Turkish Journal of Chemistry
Segmented polyurethanes were synthesized by the reactions of poly($\varepsilon $-caprolactone) (PCL)-diol and 1,6-hexamethylene diisocyanate through bulk polymerization without using solvent, initiator, or catalyst. Phase separation and hydrogen bond formation between hard segments or between hard and soft segments were examined by Fourier transform infrared spectroscopy (FTIR)-ATR and X-ray diffraction (XRD), while physical and mechanical properties were studied by atomic force microscope, differential scanning calorimeter, dynamic mechanical analysis, and tensile tester. When the diisocyanate content was increased, deconvolution results of FTIR-ATR in C$=$O and N-H regions demonstrated better miscibility of the segments and XRD results showed a significant decrease in the …
An Insight Into The Therapeutic Potential Of Piperazine-Based Anticancer Agents, Kamran Walayat, Noor Ul Amin Mohsin, Sana Aslam, Matloob Ahmad
An Insight Into The Therapeutic Potential Of Piperazine-Based Anticancer Agents, Kamran Walayat, Noor Ul Amin Mohsin, Sana Aslam, Matloob Ahmad
Turkish Journal of Chemistry
The piperazine ring system is among the medicinally important nitrogen-containing heterocyclic ring systems and is exploited for the synthesis of various drug molecules. A number of FDA-approved anticancer drugs contain piperazine rings and thus it is considered as an attractive scaffold having extraordinary potential for the development of new anticancer agents. In recent decades there has been an alarming increase in the number of people suffering from cancerous diseases all over the world, which resulted in an extraordinary increase in research reports on new anticancer drug candidates. The aim of this article is to highlight the structural parameters imparting anticancer …
1,2-Dibromotetrachloroethane: An Efficient Reagent For Many Transformations By Modified Appel Reaction, Selçuk Eşsi̇z, Ari̇f Daştan
1,2-Dibromotetrachloroethane: An Efficient Reagent For Many Transformations By Modified Appel Reaction, Selçuk Eşsi̇z, Ari̇f Daştan
Turkish Journal of Chemistry
An efficient and facile method has been developed for the synthesis of alkyl bromides from various alcohols under mild conditions using a triphenylphosphine (PPh$_{3})$/1,2-dibromotetrachloroethane (DBTCE) complex in excellent yields and very short time (5 min). This method can also be applied for the transformation of chiral alcohols to their corresponding bromides in very high enantiomeric excess. The PPh$_{3}$/DBTCE complex is also successfully applied to ring-opening reactions of cyclic ethers in mild conditions. Esterification, amidation, and formation of acid anhydrides under very mild experimental conditions are also successfully accomplished by following a modification of the Appel reaction protocol in this work.
Chemistry Of Endemic \Textit{Tanacetum Mucroniferum} Hub.-Mor. {\&} Grierson Extracts And Three New Sesquiterpene Lactones, Hüseyi̇n Servi̇, Nezhun Gören
Chemistry Of Endemic \Textit{Tanacetum Mucroniferum} Hub.-Mor. {\&} Grierson Extracts And Three New Sesquiterpene Lactones, Hüseyi̇n Servi̇, Nezhun Gören
Turkish Journal of Chemistry
Tanacetum mucroniferum Hub.-Mor. & Grierson was collected from Sakaltutan in Erzincan Province of Turkey. Comparative phytochemical investigation was carried out on the ethyl acetate and methanol extracts of the plant. The secondary metabolites were isolated and purified by chromatographic methods such as column chromatography, medium pressure liquid chromatography, high-performance thin-layer chromatography, and preparative thin-layer chromatography. The extracts of the aerial parts of Tanacetum mucroniferum yielded three new sesquiterpene lactones and some known compounds, namely two sesquiterpene lactones, six flavonoids, three coumarins, and one triterpene. Structures of isolated compounds were determined by IR, UV, $^{1}$H NMR, APT, COSY, HSQC, HMBC, NOESY, …
The Effect Of Washing On Stabilized And Unstabilized Low-Density Polyethylene Films Naturally Weathered In A Sub-Saharan Region (Ghardaia, Algeria, Souad Behissa, Salem Fouad Chabira, Nourelhouda Benmiloud, Mohamed Sebaa
The Effect Of Washing On Stabilized And Unstabilized Low-Density Polyethylene Films Naturally Weathered In A Sub-Saharan Region (Ghardaia, Algeria, Souad Behissa, Salem Fouad Chabira, Nourelhouda Benmiloud, Mohamed Sebaa
Turkish Journal of Chemistry
The effect of washing stabilized and unstabilized blown extruded films of low-density polyethylene (LDPE) used for greenhouse coverings naturally weathered in a sub-Saharan facility at Ghardaia (Algeria) for 19 and 6 months, respectively, was studied. A comparison between unwashed and daily washed samples was done. The changes in the films' properties were followed at regular intervals using various characterization methods (physicochemical and mechanical). Although in both cases the chemical species formed due to the weathering were qualitatively the same, they essentially differed in their concentrations, namely they were higher for the washed samples than for the unwashed ones. Inversely, the …
Effect Of Brij 35 And Saponin Surfactants On Adsorption Of Diethylstilbestrol As An Emerging Estrogenic Contaminant By Clinoptilolite In Batch And Fixed-Bed Column Experiments, Reyhaneh Saadi, Reza Fazaeli, Leila Vafajoo, Iraj Naser
Effect Of Brij 35 And Saponin Surfactants On Adsorption Of Diethylstilbestrol As An Emerging Estrogenic Contaminant By Clinoptilolite In Batch And Fixed-Bed Column Experiments, Reyhaneh Saadi, Reza Fazaeli, Leila Vafajoo, Iraj Naser
Turkish Journal of Chemistry
In this study, natural clinoptilolite was modified by saponin and Brij 35 surfactants to remove diethylstilbestrol (DES) from wastewater in batch and continuous systems. The optimum pH, amount of adsorbent, contact time, and temperature were 11, 10 g/L, 12 h, and 35 $^{\circ}$C, respectively, for the process. The equilibrium data agreed well with the Langmuir isotherm for natural clinoptilolite (NC), natural clinoptilolite modified by Brij 35 (NC-Brij), and natural clinoptilolite modified by saponin surfactants (NC-saponin) compared to other isotherms. The maximum adsorption capacities resulting from the Langmuir isotherm for NC, NC-Brij, and NC-saponin were 8.012, 23.64, and 39.525 mg/g, respectively. …
Gas Sensing With Hexafluoroisopropanol Substituted Phthalocyanines And Vic-Dioximes: A Comparative Study, Mika Harbeck, Zafer Şen, Di̇lek Erbahar, Gülay Gümüş, Emel Musluoğlu
Gas Sensing With Hexafluoroisopropanol Substituted Phthalocyanines And Vic-Dioximes: A Comparative Study, Mika Harbeck, Zafer Şen, Di̇lek Erbahar, Gülay Gümüş, Emel Musluoğlu
Turkish Journal of Chemistry
Phthalocyanines (Pcs) are established sensitive materials for chemical gas sensors due to their superb sensing characteristics and the achievable manifold in their analyte interaction properties. Their sorption properties are determined by the metal ion center and substituents attached to the periphery of the ring system. Similarly, vic-dioximes can be modified in their sorption properties and employed as sensitive materials. In this work, a nickel Pc and various vic-dioximes functionalized with the same hexafluoroisopropanol moiety are assessed and compared in their gas-sensing properties using the quartz crystal microbalance for the first time. This specific substituent is selected for its hydrogen bond …
Magnetic Solid-Phase Extraction Based On Coriolus Versicolor-Immobilized $\Gamma $-Fe$_{2}$O$_{3}$ Nanoparticles For Preconcentration And Determination Of Al(Iii) In Water And Food Samples, Sadi̇n Özdemi̇r, Mustafa Serkan Yalçin, Ersi̇n Kilinç, Mustafa Soylak
Magnetic Solid-Phase Extraction Based On Coriolus Versicolor-Immobilized $\Gamma $-Fe$_{2}$O$_{3}$ Nanoparticles For Preconcentration And Determination Of Al(Iii) In Water And Food Samples, Sadi̇n Özdemi̇r, Mustafa Serkan Yalçin, Ersi̇n Kilinç, Mustafa Soylak
Turkish Journal of Chemistry
A method for preconcentration of Al(III) prior to its determination by inductively coupled plasma-optical emission spectrometry (ICP-OES) was developed because the sensitivity of ICP-OES is insufficient for trace-level measurement of Al(III). The method is based on the use of Coriolus versicolor}-immobilized $\gamma $-Fe$_{2}$O$_{3}$ magnetic nanoparticles as a solid phase sorbent. The best experimental conditions were found as pH 6.0, 2.0 mL/min flow rate, 100 mg amount of C. versicoloron 150 mg of $\gamma $-Fe$_{2}$O$_{3}$ nanoparticles, and 500 mL of sample volume. The Al(III) absorbed on biosorbent was eluted with 5.0 mL of 1.0 mol/L HCl. Limit of detection, limit of …
Silylation Of Epoxidized Soybean Oil With Triethoxysilanes, Synthesis And Characterization Of Their Polyurethanes, Aynur Özşeker, Kemal Karadeni̇z, Mustafa Yasi̇n Şen
Silylation Of Epoxidized Soybean Oil With Triethoxysilanes, Synthesis And Characterization Of Their Polyurethanes, Aynur Özşeker, Kemal Karadeni̇z, Mustafa Yasi̇n Şen
Turkish Journal of Chemistry
Silylation of epoxidized soybean oil (ESBO) was carried out by epoxy ring opening reaction of methoxy and ethoxy silane compounds. $^{1}$H NMR and FTIR spectra confirmed that two novel bio-based polyols, PSiTh and PSiAm, were obtained through the ring opening of epoxy by the mercapto and amino moieties of MPTMS and APTES, respectively. Polyurethanes of these polyols were prepared using 4,4'- methylene-bis(phenyl isocyanate) (MDI) to incorporate silanol groups into polymer network and were labeled as PUSiTh and PUSiAm, respectively. To see the impact of silanol and phosphorous groups on flame retardant properties, the chain extended polyurethanes, PUSiThCE and PUSiAmCE were …
Crystal Structure And Hirshfeld Surface Analysis Of 1,2-Ethylene-Bis (Para-Methyl Pyridinium) Dichromate As A New Selective And Mild Agent In Oxidation Of Alcohols, Mostafa Gholizadeh, Mehrdad Pourayoubi, Mohammad Reza Houssiendokht, Hadi Amiri Rudbari, Masoumeh Farimaneh, Anahid Saneei, Giuseppe Bruno
Crystal Structure And Hirshfeld Surface Analysis Of 1,2-Ethylene-Bis (Para-Methyl Pyridinium) Dichromate As A New Selective And Mild Agent In Oxidation Of Alcohols, Mostafa Gholizadeh, Mehrdad Pourayoubi, Mohammad Reza Houssiendokht, Hadi Amiri Rudbari, Masoumeh Farimaneh, Anahid Saneei, Giuseppe Bruno
Turkish Journal of Chemistry
1,2-Ethylene-bis(para-methyl pyridinium) dichromate, (C$_{14}$H$_{18}$N$_{2})$[Cr$_{2}$O$_{7}$], is used as a new oxidizing agent in conversion of some alcohols to their corresponding carbonyl compounds in CH$_{3}$CN solvent and also under solvent-free conditions. In both procedures, high conversion percentages are observed. However, a much shorter reaction time is achieved in solvent-free conditions. For allylic alcohols, the C=C bond is not oxidized and the examined saturated alcohol in this work (i.e. cyclo-hexanol) remains intact, which illustrates the mild nature of reagent used. The structure of the reagent is investigated by single-crystal X-ray diffraction analysis. The C--H$\cdots$O and O$\cdots \pi$ interactions are the most important features …
New Diazo-Containing Phenolic Oximes: Structural Characterization, Computational Studies, And Solvent Extraction Of Cu(Ii), Ni(Ii), And Zn(Ii) Ions, Muharrem Karabörk, Hi̇lal Kirpik, Koray Sayin, Muhammet Köse
New Diazo-Containing Phenolic Oximes: Structural Characterization, Computational Studies, And Solvent Extraction Of Cu(Ii), Ni(Ii), And Zn(Ii) Ions, Muharrem Karabörk, Hi̇lal Kirpik, Koray Sayin, Muhammet Köse
Turkish Journal of Chemistry
In the current study, four new phenolic oxime ligands (HL1ox-HL4ox) containing diazo groups (-N$=$N-) were synthesized and used for liquid-liquid extraction of heavy metal ions [Cu(II), Ni(II), and Zn(II)]. The new compounds were characterized by analytical and spectroscopic methods. Solid-state structures of HL1ox-HL3ox were determined by single-crystal X-ray diffraction studies. Hirshfeld surface analysis of the compounds was performed to determine the contribution of different intermolecular contacts to the stability of the structures. The HL1ox-HL4ox ligands showed higher extraction performance for Cu(II) ion than Ni(II) and Zn(II) ions. The effect of pH on extraction capacity was investigated and the oxime compounds …
Synthesis Of Novel Azo Linkage-Based Schiff Bases Including Anthranilic Acid And Hexanoic Acid Moieties: Investigation Of Azo-Hydrazone And Phenol-Keto Tautomerism, Solvatochromism, And Ionochromism, Özlem Özdemi̇r
Turkish Journal of Chemistry
Two new azo-Schiff base receptors (L$_{{1}}$ and L$_{{2}})$ containing azo and azomethine groups with a conjugated group (benzyl ring of anthranilic acid, in L$_{{1}})$ and electron-donating group (alkyl chain of hexanoic acid, in L$_{{2}})$ were synthesized and characterized. Azo-hydrazone/phenol-keto tautomerism and solvatochromism were investigated. Studying their sensing ability towards cations (Co$^{2+}$, Cu$^{2+}$, Zn$^{2+}$, Ni$^{2+}$, Pb$^{2+}$, Cd$^{2+}$, Mn$^{2+}$, Fe$^{3+}$, Cr$^{3+}$, and Al$^{3+})$, high sensitivity and selectivity were recorded for Fe$^{3+}$ by naked eye and UV-Vis spectra in DMF-aqueous HEPES buffer (v:v, 1:1, pH 6.8). The color of L$_{{1}}$ and L$_{{2}})$ solutions instantly changed from yellow to deep orange and pale orange. …
3d-Qsar/Hqsar-Based Analysis Of Bioconcentration And Molecular Modification Of Monophenyl Aromatic Compounds, Qing Li, Wenwen Gu, Yu Li
3d-Qsar/Hqsar-Based Analysis Of Bioconcentration And Molecular Modification Of Monophenyl Aromatic Compounds, Qing Li, Wenwen Gu, Yu Li
Turkish Journal of Chemistry
Comparative molecular field analysis (CoMFA) and comparative molecular similarity indices analysis (CoMSIA) of three-dimensional quantitative structure-activity relationship (3D-QSAR) models were conducted using 36 aromatic compound congeners as the training set and eight aromatic compound congeners as the test set. Logarithms of experimental bioconcentration data (logBCF) were used as dependent variables and the physicochemical properties of the aromatic compound congeners were used as independent variables. Furthermore, the molecular holographic quantitative structure--activity relationship (HQSAR) model constructed by the HQSAR module in Sybyl software was used to establish a method to find molecular activity substitution sites of bioconcentration potential by coupling the molecule …
Gold-Assembled Silica-Coated Cobalt Nanoparticles As Efficient Magnetic Separation Units And Surface-Enhanced Raman Scattering Substrate, Lütfi̇ye Sezen Yildirim, Murat Kaya, Mürvet Volkan
Gold-Assembled Silica-Coated Cobalt Nanoparticles As Efficient Magnetic Separation Units And Surface-Enhanced Raman Scattering Substrate, Lütfi̇ye Sezen Yildirim, Murat Kaya, Mürvet Volkan
Turkish Journal of Chemistry
Magnetic and optical bifunctional nanoparticles that combine easy separation, preconcentration, and efficient SERS capabilities have been fabricated with high sensitivity and reproducibility through a low-cost method. These gold nanoparticles attached on magnetic silica-coated cobalt nanospheres (Co@SiO$_{2}$/AuNPs) display the advantage of strong resonance absorption due to gaps at nanoscale between neighboring metal nanoparticles bringing large field enhancements, known as "hot spots". The prepared particles can be controlled by using an external magnetic field, which makes them very promising candidates in biological applications and Raman spectroscopic analysis of dissolved organic species. The magnetic property of the prepared particles lowers the detection limits …
Computational Investigation Of Influenza A Virus M2 Protein Inhibition Mechanism By Ion Channel Blockers, Mehmet Özbi̇l
Computational Investigation Of Influenza A Virus M2 Protein Inhibition Mechanism By Ion Channel Blockers, Mehmet Özbi̇l
Turkish Journal of Chemistry
The M2 protein of the influenza A virus, responsible for flu, is a homotetramer transmembrane protein, forming a transmembrane ion channel, where His 37s act as pH sensors and Trp 41s and Asp 44s act as channel gates. Opening of this channel leads to transfer of virus RNA into the human host. Thus, blocking this transfer is an important pharmaceutical strategy to stop infection. As a result of viral drug resistance, commercially available channel inhibitors, rimantadine (RIM) and amantadine (AMA), are not as effective as they used to be. Understanding binding sites and outcomes of binding will lead to new …
New Flavonoid Glycosides Conjugates: Synthesis, Characterization, And Evaluation Of Their Cytotoxic Activities, Sawssen Souiei, Fatima Bousejra-El Garah, Mohamed Amine Belkacem, Mansour Znati, Jalloul Bouajila, Hichem Ben Jannet
New Flavonoid Glycosides Conjugates: Synthesis, Characterization, And Evaluation Of Their Cytotoxic Activities, Sawssen Souiei, Fatima Bousejra-El Garah, Mohamed Amine Belkacem, Mansour Znati, Jalloul Bouajila, Hichem Ben Jannet
Turkish Journal of Chemistry
A series of novel halogenated 3-hydroxyflavones (3HFs) were prepared by reacting halogenated hydroxyacetophenones with the appropriate aromatic aldehyde. Glycosylation of 3HFs with acetobromoglucose and deprotection of the acetyl protective groups afforded the desired 3-$O$-flavonoids glycosides in satisfactory yields. All the prepared compounds were tested for their cytotoxic activity against HCT-116, MCF-7, and OVCAR-3 human cancer cell lines. The 3HFs exhibited higher cytotoxic activities compared with the glycosylated flavonoids. Overall, the structure-activity relationship study showed that the introduction of glycoside moiety at the C-3 OH position does not improve the bioactivity.
Acid-Activated Clay As Heterogeneous And Reusable Catalyst For The Synthesis Of Bioactive Cyclic Ketal Derivatives, Wided Hagui, Rym Essid, Sondes Amri, Nadia Fares, Mohamed Khabbouchi, Olfa Tabbene, Ferid Limam, Ezzedine Srasra, Neji Besbes
Acid-Activated Clay As Heterogeneous And Reusable Catalyst For The Synthesis Of Bioactive Cyclic Ketal Derivatives, Wided Hagui, Rym Essid, Sondes Amri, Nadia Fares, Mohamed Khabbouchi, Olfa Tabbene, Ferid Limam, Ezzedine Srasra, Neji Besbes
Turkish Journal of Chemistry
A new heterogeneous acid catalyst based on a natural resource, Tunisian clay (Clay-H0.5), has been prepared and characterized by FT-IR, FE-SEM, and powder X-ray diffraction (XRD), as well as chemical composition, cation exchange capacity, specific surface area, and pore volume. Acid treatment for 0.5 h enlarged the surface area from 78.24 to 186.10 m$^{2}$/g and pore volume (PV) from 0.186 to 0.281 cm$^{3}$/g. The catalytic activity of this material was investigated in ketalization reaction under mild solvent-free conditions. This achieved up to 92% isolated yield for only 10 wt.% of the catalyst. This environmentally friendly method has advantages such as …
Boric Acid As An Efficient And Green Catalyst For The Synthesis Of 2-Amino-4,6-Diarylnicotinonitrile Under Microwave Irradiation In Solvent-Free Conditions, Zahra Hosseinzadeh, Ali Ramazani, Nima Razzaghi-Asl, Katarzyna Slepokura, Tadeusz Lis
Boric Acid As An Efficient And Green Catalyst For The Synthesis Of 2-Amino-4,6-Diarylnicotinonitrile Under Microwave Irradiation In Solvent-Free Conditions, Zahra Hosseinzadeh, Ali Ramazani, Nima Razzaghi-Asl, Katarzyna Slepokura, Tadeusz Lis
Turkish Journal of Chemistry
Microwave irradiation has been used to improve the one-pot synthesis of substituted 2-amino-4,6-diarylnicoti- nonitrile in the presence of boric acid as an efficient and green catalyst under solvent-free conditions within 48--60 s. All the analogs that have not been reported previously were characterized by their melting points, IR, $^{1}$H NMR, and $^{13}$C NMR spectra. One of the structures was verified by the analysis of a single crystal. The reported synthetic procedure provided remarkable advantages such as short reaction times, excellent yield, facile workup, and the use of a green catalyst.
Design, Synthesis, And Evaluation Of The Antimycobacterial Activity Of 3-Mercapto-1,2,4-Triazole--Pyrrole Hybrids, Gheorghe Roman, Andra-Cristina Bostanaru, Valentin Nastasa, Mihai Mares
Design, Synthesis, And Evaluation Of The Antimycobacterial Activity Of 3-Mercapto-1,2,4-Triazole--Pyrrole Hybrids, Gheorghe Roman, Andra-Cristina Bostanaru, Valentin Nastasa, Mihai Mares
Turkish Journal of Chemistry
A series of 3-mercapto-1,2,4-triazole--pyrrole hybrids was designed as antimycobacterial agents by employing 5-(4-(1$H$-pyrrol-1-yl)phenyl)-4$H$-1,2,4-triazole-3-thiol as the scaffold onto which several types of moieties were introduced in the triazole ring at N-4 and N-2 and as substituents of the mercapto function. The aforementioned moieties are an allyl or a phenyl moiety at N-4; an aminomethyl group at N-2; or methyl, substituted benzyl, ethoxycarbonylmethyl, or substituted phenacyl at sulfur. Investigation of the compounds in the resulting library as growth inhibitors of Mycobacterium smegmatis showed that their minimum inhibitory concentration was higher than 64 mg/L.
A Case Study Of Antiaromaticity: Carbomethoxy Cyclopropenyl Anion, Zi̇kri̇ Altun, Erdi̇ Ata Bleda, Carl Trindle
A Case Study Of Antiaromaticity: Carbomethoxy Cyclopropenyl Anion, Zi̇kri̇ Altun, Erdi̇ Ata Bleda, Carl Trindle
Turkish Journal of Chemistry
The simplest ideas of antiaromaticity refer to regular monocyclic systems and the eigenfunctions of the H\"{u}ckel Hamiltonian for 4n $\pi $ electrons in such systems. The antiaromaticity is expressed in the energy penalty for such idealized systems relative to the H\"{u}ckel energy for 2n noninteracting $\pi $ pairs. Observed systems seldom achieve the regular planar geometry assumed in this picture, owing to their ability to ease the antiaromaticity penalty by departures from the regular geometry and also by export of the 4n $\pi $ electrons' charge to substituents. In this report we estimate numerical values for the stabilization derived from …
An Exploration Of New Avenues Regarding Deep Tissue Penetration And Higher Singlet Oxygen Efficiencies: Novel Near-Ir Photosensitizers For Photodynamic Therapy, Ni̇sa Yeşi̇lgül, Bi̇lal Kiliç
An Exploration Of New Avenues Regarding Deep Tissue Penetration And Higher Singlet Oxygen Efficiencies: Novel Near-Ir Photosensitizers For Photodynamic Therapy, Ni̇sa Yeşi̇lgül, Bi̇lal Kiliç
Turkish Journal of Chemistry
A series of novel BODIPY-bearing electron-withdrawing groups at the meso position are reported here. According to the optical measurements, it may be clearly seen that the introduction of electron-donating groups into 3,5-positions and the presence of electron-withdrawing groups at the meso position of the BODIPY core resulted in spectacular bathochromic shifts (up to ∼ 304 nm), and the projected photosensitizers had absorption bands in the therapeutic window of the electromagnetic spectrum (600-900 nm). The absorption maxima of compounds 4,5,6, and 7 were at 886 nm, 890 nm, 760 nm, and 761 nm, respectively. The singlet oxygen generation experiments revealed that …
Intermolecular Complexes Of Halocyclopropenone Derivatives With The Hypohalous Acids Hof, Hocl, Hobr, And Hoi, Dariush Mirzaei, Abedien Zabardasti, Yaghoub Mansourpanah
Intermolecular Complexes Of Halocyclopropenone Derivatives With The Hypohalous Acids Hof, Hocl, Hobr, And Hoi, Dariush Mirzaei, Abedien Zabardasti, Yaghoub Mansourpanah
Turkish Journal of Chemistry
The intermolecular interactions between halocyclopropenone derivatives (HC$_{3}$OX; X $=$ I, Br, Cl, and F) and hypohalous acids (HOY; Y $=$ I, Br, Cl, and F) were studied via the MP2 method utilizing the aug-cc-pVTZ and aug-cc-pVTZ(-PP) basis sets. The three types of complexes were hydrogen bonds, halogen bonds, and complexes containing both hydrogen and halogen bonds. The results obtained indicated that interactions in the Type 1 complexes were stronger than those in Types 2 and 3. The H-O bonds revealed red shifts with complex formation in Types 1 and 2. The O-Y bonds displayed red shifts in the Type 3 …
Synthesis And Antitumor Activities Of 2-(Piperidin-4-Yl)-Thiazole-4-Carboxamides Analogues Of Tubulysins, Xiangfu Peng, Mingsha Shao, Shuchao Ma, Lei Yao
Synthesis And Antitumor Activities Of 2-(Piperidin-4-Yl)-Thiazole-4-Carboxamides Analogues Of Tubulysins, Xiangfu Peng, Mingsha Shao, Shuchao Ma, Lei Yao
Turkish Journal of Chemistry
}Tubulysins are a family of natural products that exhibit potent antitumor activities, which have attracted much attention from synthetic and medicinal chemists. Previous attempts to aromatize the Tuv part of tubulysin analogues led to a loss in antitumor activity, which suggested that the Ile and Tuv fragments of these analogues were adopting different conformations than the natural products. In this study, a series of 2-(piperidin-4-yl)-thiazole-4-carboxamides have been prepared to investigate whether an intramolecular H-bond between key NH and OH groups is responsible for the conformational control. The antitumor activities of these analogues have been screened using MDA-MB-231-breast, Siha-cervical, MCF7-breast, and …
A Microwave-Assisted Highly Stereoselective One-Pot Wittig Reaction Under Solvent-Free Conditions, Kalyani Rajkumari, Bittu Lama, Lalthazuala Rokhum
A Microwave-Assisted Highly Stereoselective One-Pot Wittig Reaction Under Solvent-Free Conditions, Kalyani Rajkumari, Bittu Lama, Lalthazuala Rokhum
Turkish Journal of Chemistry
We report a novel microwave-assisted two-step, one-pot protocol for the synthesis of olefins (alkenes) via Wittig reaction. The reaction was carried out under solvent-free conditions using basic alumina both as a heterogeneous catalyst and a solid support. Varieties of aromatic aldehydes were converted into their corresponding olefins within 30-50 min with good to excellent yields. An excellent predominance of E-isomers over Z-isomers (up to 100% E-selectivity) for all the olefin products was observed. This showed the attractive stereocontrol of our reported protocol. In addition, owing to the solid-state nature of the reactions, our procedure prevented the need for tedious aqueous …
Effect Of Fe Substitution On The Partial Oxidation Of Methane To Syngas Over La$_{0.7}$Sr$_{0.3}$Co$_{1-Y}$Fe$_{Y}$O$_{3-\Delta}$ Perovskites, Adilah Aliyatulmuna, Perry Burhan, Bambang Prijamboedi, Hamzah Fansuri, Irmina Kris Murwani
Effect Of Fe Substitution On The Partial Oxidation Of Methane To Syngas Over La$_{0.7}$Sr$_{0.3}$Co$_{1-Y}$Fe$_{Y}$O$_{3-\Delta}$ Perovskites, Adilah Aliyatulmuna, Perry Burhan, Bambang Prijamboedi, Hamzah Fansuri, Irmina Kris Murwani
Turkish Journal of Chemistry
In this research, a series of La$_{0.7}$Sr$_{0.3}$Co$_{1-y}$Fe$_{y}$O$_{3-\delta }$ ($y =$ 0.0--0.4) was successfully synthesized by a solid-state reaction method and syngas production studies were performed using gas chromatography. Thermogravimetric analysis characterized the concentration of Fe$^{3+}$, which gave a low H$_{2}$/CO ratio over La$_{0.7}$Sr$_{0.3}$Co$_{1-y}$Fe$_{y}$O$_{3-\delta }$ without the presence of molecular oxygen. All samples possessed a purely rhombohedral structure. The incorporation of more Fe increased the lattice parameter and changed XRD peaks of the La$_{1-x}$Sr$_{x}$Co$_{0.8}$Fe$_{0.2}$O$_{3}$ from sharp and single to double. Among the catalyst powders tested for syngas production activity, La$_{0.7}$Sr$_{0.3}$Co$_{0.6}$Fe$_{0.4}$O$_{3-\delta }$ ($y =$ 0.4) had the low molar ratio of H$_{2}$/CO …
Electrochemical Oxidation Of Curcuminoids: An Experimental And Computational Investigation, Zeynep Kalaycioğlu, Nurgül Karadaş, Mehmet Emi̇n Çinar, Si̇bel Ayşil Özkan, Duri̇şehvar Özer Ünal, Ayşegül Gölcü, Fatma Bedi̇a Eri̇m
Electrochemical Oxidation Of Curcuminoids: An Experimental And Computational Investigation, Zeynep Kalaycioğlu, Nurgül Karadaş, Mehmet Emi̇n Çinar, Si̇bel Ayşil Özkan, Duri̇şehvar Özer Ünal, Ayşegül Gölcü, Fatma Bedi̇a Eri̇m
Turkish Journal of Chemistry
Curcuminoids, reported to have important biological properties, such as antioxidant, anti-Alzheimer, and antidiabetic properties, comprise curcumin (CRM; 1,7-bis [4-hydroxy-3-methoxyphenyl]-1,6-heptadiene-3,5-dione) and its derivatives demethoxycurcumin (DMC; (E,6E)-1-(3,4-dimethoxy-cyclohexyl)-7-(3,4-dimethoxyphenyl)hepta-1,6-diene-3,5-dione) and bisdemethoxycurcumin (BDMC; 1,7-bis[4-hydroxyphenyl]-1,6-heptadiene-3,5-dione). Their electrochemical oxidations are thoroughly explored by applying cyclic and differential pulse voltammetric techniques. The dependence of current intensities and potentials on pH, concentration, scan rate, and nature of the buffer was investigated. The outcome is supported by density functional theory computations indicating the transfer of 4-e$^{-}$/H$^{+}$, 6-e$^{-}$/H$^{+}$, and 8-e$^{-}$/H$^{+}$ couples involved in the oxidation mechanisms of CRM, DMC, and BDMC, respectively, leading to the formation of the same oxidized product.