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Articles 12631 - 12660 of 13177
Full-Text Articles in Entire DC Network
Synthesis And Characterization Of 4-(Alkylaminoisonitrosoacetyl)Diphenyl Ether And Some Of Their Metal Complexes, Ahmet Coşkun, Funda Yilmaz
Synthesis And Characterization Of 4-(Alkylaminoisonitrosoacetyl)Diphenyl Ether And Some Of Their Metal Complexes, Ahmet Coşkun, Funda Yilmaz
Turkish Journal of Chemistry
4-(Chloroacetyl)diphenyl ether (I) was synthesized from chloroacetyl chloride and diphenyl ether in the presence of AlCl_3 as catalyst in a Friedel-Crafts reaction. Subsequently, its keto oxime (II) derivative was prepared. Then 3 new substituted 4-(alkylaminoisonitrosoacetyl)diphenyl ether ligands derived from 4-(phenoxy)phenyloxylohydroxymoyl chloride and corresponding amines were synthesized. The following aromatic and aliphatic amines were used for the ligands ethanolamine, 2-amino-4-methylphenol, and 2-(aminomethyl) pyridine. Mononuclear or binuclear Co(II), Ni(II), Cu(II), and Cd(II) complexes of the ligands were synthesized. The structures of these ligands were identified by FT-IR, ^1H-NMR, and ^{13}C-NMR spectral data and elemental analysis, and the structures of the complexes were …
Cyanoacetamide Derivatives As Synthons In Heterocyclic Synthesis, Ahmed Ali Fadda, Samir Bondock, Ramy Rabie, Hassan Ali Etman
Cyanoacetamide Derivatives As Synthons In Heterocyclic Synthesis, Ahmed Ali Fadda, Samir Bondock, Ramy Rabie, Hassan Ali Etman
Turkish Journal of Chemistry
This review presents a systematic and comprehensive survey of the methods of preparation and the chemical reactivity of cyanoacetamide derivatives. These compounds are important intermediates for the synthesis of a variety of otherwise difficult to obtain synthetically useful and novel heterocyclic systems.
Microcontact Printing Of An Alkylsilane Monolayer On The Surface Of Glass, Gülşi̇n Arslan, Mustafa Özmen, İmren Hatay, İlkay Hi̇lal Gübbük, Mustafa Ersöz
Microcontact Printing Of An Alkylsilane Monolayer On The Surface Of Glass, Gülşi̇n Arslan, Mustafa Özmen, İmren Hatay, İlkay Hi̇lal Gübbük, Mustafa Ersöz
Turkish Journal of Chemistry
This paper describes the use of microcontact printing (\mu CP) for patterning of self-assembled monolayers (SAMs) of (3-aminopropyl)-triethoxysilane (APTES) and octadecyltrichloro silane (OTS) on the surface of glass and functionalization of alkylsilane monolayers. After activation of the glass surface, which was patterned with OTS using a poly(dimethylsiloxane) (PDMS) stamp, the remaining bars of the surfaces were treated with APTES and then treated with a dye solution. The characterization of printed silane compounds was confirmed using fluorescence microscopy on the basis of the reaction between terminal amine groups of APTES and thionylchloride of Rhodamine-B dye. Quantitative 3-dimensional profiling was performed for …
A Hydrogen Ion-Selective Poly(Vinyl Chloride) Membrane Electrode Based On Calix[4]Arene As A Perchlorate Ion-Selective Electrode, Esi̇n Canel, Sevcan Erden, Ayça Demi̇rel Özel, Sahahabuddin Memon, Mustafa Yilmaz, Esma Kiliç
A Hydrogen Ion-Selective Poly(Vinyl Chloride) Membrane Electrode Based On Calix[4]Arene As A Perchlorate Ion-Selective Electrode, Esi̇n Canel, Sevcan Erden, Ayça Demi̇rel Özel, Sahahabuddin Memon, Mustafa Yilmaz, Esma Kiliç
Turkish Journal of Chemistry
A hydrogen ion-selective electrode was prepared using 5,11,17,23-tetra-tert-butyl-25,26,27,28-tetracyanometoxy-calix[4]arene and the possibility of its use as a perchlorate ion-selective electrode was investigated using its characteristic of becoming perchlorate sensitive in acidic regions. The electrode of the optimum characteristic had a composition of 1% ionophore, 66% o-NPOE, and 33% PVC. This electrode exhibited a linear response over the range 1.0 \times 10^{-1}-1.0 \times 10^{-5} M of perchlorate with a slope of 48.7 \pm 0.5 mV per p[ClO_4]. The effects of the pH and the membrane composition were also investigated. The lifetime of the electrode was at least 4 months and its response …
Synthesis Of Some New 4-Oxo-4h-Chromene Derivatives Bearing Nitrogen Heterocyclic Systems As Antifungal Agents, Tarik El-Sayed Ali, Salah Abdel-Aghfaar Abdel-Aziz, Hafez Metwali El-Shaaer, Faten Ismail Hanafy, Ali Zaky El-Fauomy
Synthesis Of Some New 4-Oxo-4h-Chromene Derivatives Bearing Nitrogen Heterocyclic Systems As Antifungal Agents, Tarik El-Sayed Ali, Salah Abdel-Aghfaar Abdel-Aziz, Hafez Metwali El-Shaaer, Faten Ismail Hanafy, Ali Zaky El-Fauomy
Turkish Journal of Chemistry
Some new 4-oxo-4H-chromone derivatives bearing nitrogen heterocyclic systems were achieved by treatment of 3-[(4-aminophenylimino) methyl]-6-chloro-4-oxo-4H-chromene (2) with some aldehydes, cyclic oxygen, and halogen compounds, followed by heterocyclization. Significant antifungal activities were observed for some of the prepared compounds. Structures of all products were confirmed by elemental analysis, IR, ^1H-NMR, and mass spectra.
Synthesis And Antimicrobial Evaluation Of Novel Di-Triazoles And 4-Arylidene Amino 4,5 Dihydro-1h-[1,2,4] Triazole-5-One Derivatives, Yasemi̇n Ünver, Esra Düğdü, Kemal Sancak, Mustafa Er, Şengül Alpay Karaoğlu
Synthesis And Antimicrobial Evaluation Of Novel Di-Triazoles And 4-Arylidene Amino 4,5 Dihydro-1h-[1,2,4] Triazole-5-One Derivatives, Yasemi̇n Ünver, Esra Düğdü, Kemal Sancak, Mustafa Er, Şengül Alpay Karaoğlu
Turkish Journal of Chemistry
A series of novel di-[3(thiophen-2-yl-methyl)-4,5-dihydro-1H- [1,2,4]triazole-5-one-4yl]n-alkanes (2a-h) were obtained by the reaction of N'-1-ethoxy-2-thiophen-2-yl-ethylydene hydrazino carboxylic acid ethyl ester (1) and diamines. Compound 3 was reacted with aldehydes and 4-(arylidene-amino)-3-thiophen-2-yl-methyl-4,5-dihydro-1H-[1,2,4] triazole-5-ones (4, 5, and 8) with Schiff base character were synthesized. (4-(arylidene-amino)-5-oxo-3-thiophen-2-yl-methyl-4,5- dihydro-1H-[1,2,4]triazole-1-yl)-acetic acid ethyl esters (6, 7, and 9) were obtained by the reaction of 4-(arylidene-amino)-3-thiophen-2-yl- methyl-4,5-dihydro-1H-[1,2,4]triazole-5-ones (4, 5, and 8) and ethyl bromoacetate. The structures of the new compounds were inferred through IR, ^1H/^{13}C NMR, elemental analyses, and mass spectral data. Compound 8i was characterized by IR, ^1H/^{13}C NMR, elemental analyses, mass, and X-ray spectral techniques. Geometry optimization …
Preparation Of 1,5-Diketones By Addition Of Cyclohexanone To Chalcones Under Solvent-Free Phase Transfer Catalyst Condition, Mustafa Ceylan, Hayretti̇n Gezegen
Preparation Of 1,5-Diketones By Addition Of Cyclohexanone To Chalcones Under Solvent-Free Phase Transfer Catalyst Condition, Mustafa Ceylan, Hayretti̇n Gezegen
Turkish Journal of Chemistry
Eight different chalcone-1,5-diketone derivatives (5a-h) were prepared by the reaction of chalcone derivatives (3a-h) with cyclohexanone under the solvent-free phase transfer catalyst condition with modarate to high yields. The mechanistic pathway of the reaction can be explained by the Michael-type addition of cyclohexanone to chalcone derivatives (3a-h).
Investigation Of Solid State Synthesis And Characterizations Of Novel Sodium Rare-Earth Oxyphosphates, Semi̇h Seyyi̇doğlu, Maci̇t Özenbaş, Ayşen Yilmaz
Investigation Of Solid State Synthesis And Characterizations Of Novel Sodium Rare-Earth Oxyphosphates, Semi̇h Seyyi̇doğlu, Maci̇t Özenbaş, Ayşen Yilmaz
Turkish Journal of Chemistry
A new orthorhombic phase of Na_2LaOPO_4 (sodium lanthanum oxyphosphate), and novel Na_2NdOPO_4 (sodium neodymium oxyphosphate), Na_2SmOPO_4 (sodium samarium oxyphosphate) were synthesized by solid state reactions of Na_2CO_3, NH_4H_2PO_4, and Ln_2O_3 (Ln = La, Nd, and Sm). The unit cell dimensions were calculated using their X-ray powder diffraction data, which were a = 13.60(1), b = 12.71(1), and c = 6.96(1) Å, a = 13.466(5), b = 12.547(6), and c = 6.932(5) Å, and a = 13.54(1), b = 12.577(8), and c = 7.047(5) Å, respectively, and the probable space group was Pmm2. Using the same procedure orthorhombic Na_2DyOPO_4 (sodium dysprosium …
Electrocatalytic Oxidation Of Hydroxylamine At A Quinizarine Modified Glassy Carbon Electrode: Application To Differential Pulse Voltammetry Detection Of Hydroxylamine, Mohammad Mazloumardakani, Payam Ebrahimi Karami, Hossein Naeimi, Bibifatemeh Mirjalili
Electrocatalytic Oxidation Of Hydroxylamine At A Quinizarine Modified Glassy Carbon Electrode: Application To Differential Pulse Voltammetry Detection Of Hydroxylamine, Mohammad Mazloumardakani, Payam Ebrahimi Karami, Hossein Naeimi, Bibifatemeh Mirjalili
Turkish Journal of Chemistry
The electrocatalytic behavior of hydroxylamine was studied on a glassy carbon electrode modified by electrodeposition of quinizarine, using cyclic voltammetry, chronoamperometry, and rotating disk voltammetry as diagnostic techniques. Cyclic voltammetry showed that the catalytic current of the system depends on the concentration of hydroxylamine. The magnitude of the peak current for quinizarine increased sharply in the presence of hydroxylamine and proportional to hydroxylamine concentration. The diffusion coefficient of hydroxylamine and the catalytic rate constant for the catalytic reaction of quinizarine with hydroxylamine were also estimated using a rotating disk electrode experiment. The kinetics parameters of this process were calculated, and …
Preparation And Potentiometric Study Of Promethazine Hydrochloride Selective Electrodes And Their Use In Determining Some Drugs, Nabil S. Nassory, Shahbaz A. Maki, Bashaer A. Al-Phalahy
Preparation And Potentiometric Study Of Promethazine Hydrochloride Selective Electrodes And Their Use In Determining Some Drugs, Nabil S. Nassory, Shahbaz A. Maki, Bashaer A. Al-Phalahy
Turkish Journal of Chemistry
Promethazine hydrochloride selective electrodes were constructed based on promethazine-phosphotun- gstic acid ion pair in PVC matrix membrane. The plasticizers used were di-butyl phosphate (DBP), tri-n-butyl phosphate (TBP), o-nitro phenyl octyl ether (ONPOE), and di-n-butyl phthalate (DBPH). The electrodes based on DBP, TBP, and ONPOE gave the same linear range between 1 x 10^{-4} and 1 x 10^{-1} M, while the one based on DBPH ranged between 5 x 10^{-4} and 1 x 10^{-1}M. The slopes for linear range ranged from 40 to 56 mV/decade with correlation coefficients lying between 0.9984 and 0.9993. The best detection limit was 2 x 10^{-5}M …
The Synthesis And Antimicrobial Activity Of \\\\Gamma-Butyrolactone Derivatives, Slobodan Sukdolak, Slavica Solujic-Sukdolak, Nenad Vukovic, Tanja Milosevic
The Synthesis And Antimicrobial Activity Of \\\\Gamma-Butyrolactone Derivatives, Slobodan Sukdolak, Slavica Solujic-Sukdolak, Nenad Vukovic, Tanja Milosevic
Turkish Journal of Chemistry
This paper examines the synthesis of \gamma-butyrolactone compounds 2, 3, 4, 5, and 9, and their potential antimicrobial nature and ability. The structures of all the compounds mentioned above were determined and confirmed with elemental analyses, and IR, ^1H-NMR, and ^{13}C-NMR spectroscopy. The in vitro antimicrobial activity of compounds 2, 3, 4, 5, and 9 was examined and evaluated against the following pathogens: Enterobacter aerogenes, Enterobacter cloacae, Escherichia coli, Pseudomonas aeruginosa, Staphylococcus aureus, Staphylococcus epidermidis, Streptococcus agalactiae, Aspergillus niger, and Candida albicans. Compound 5 (20 mg/mL) demonstrated high antimicrobial activity against S. epidermidis, which was closely comparable to the antimicrobial …
Synthesis And Selective Extractant Properties Of A Calixarene Thioether Derivative And Its Oligomeric Analogue, Gülderen Uysal Akkuş, Selma Aslan, F. Fulya Taktak, Shahabuddin Memon
Synthesis And Selective Extractant Properties Of A Calixarene Thioether Derivative And Its Oligomeric Analogue, Gülderen Uysal Akkuş, Selma Aslan, F. Fulya Taktak, Shahabuddin Memon
Turkish Journal of Chemistry
Herein we report the synthesis of a novel calix[4]arene thioether derivative (4) and its oligomeric analogue (5). The liquid-liquid extraction properties of these compounds towards the selected metal cations were evaluated, and it was concluded, based on our observations, that these compounds demonstrated remarkable affinity towards the selected metal cations. Nevertheless, is a good extractant and very selective for Hg^{2+} ions, whereas, in the case of its oligomeric analogue 5, the situation is quiet different. It was observed that 5 could not efficiently retain the parent selective behavior by extracting all of the selected metal ions from the aqueous to …
Hydrogenation Of Citral Over Pt And Pt-Sn Catalysts, Hi̇lal Aykaç, Selahatti̇n Yilmaz
Hydrogenation Of Citral Over Pt And Pt-Sn Catalysts, Hi̇lal Aykaç, Selahatti̇n Yilmaz
Turkish Journal of Chemistry
Hydrogenation of citral on monometallic (Pt) and bimetallic (Pt-Sn) catalysts was investigated. It was found that the catalyst activities and product distributions were different over Na-Y and Clino supports. Among monometallic catalysts, Pt/Na-Y was more selective to citronellol (3.9%) and unsaturated alcohols, geraniol and nerol, (14.1%). Sn addition increased the catalyst activities. However, its effect on product distribution differed. Yield of geraniol+nerol changed from 5.1% to 19.7% over Clino. However, selectivity to unsaturated alcohols over Na-Y decreased when it was prepared as a bimetallic catalyst support. Unsaturated alcohol formation was favored when there was a metal support interaction over monometallic …
Production Of (S)-(-)-1-(1´-Napthyl) Ethanol By Rhodotorula Glutinis Isolate Using Ram Horn Peptone, Esabi̇ Başaran Kurbanoğlu, Kani̇ Zi̇lbeyaz, Namudar I. Kurbanoğlu, Mesut Taşkin, Hamdullah Kiliç
Production Of (S)-(-)-1-(1´-Napthyl) Ethanol By Rhodotorula Glutinis Isolate Using Ram Horn Peptone, Esabi̇ Başaran Kurbanoğlu, Kani̇ Zi̇lbeyaz, Namudar I. Kurbanoğlu, Mesut Taşkin, Hamdullah Kiliç
Turkish Journal of Chemistry
The bioreduction of 1-acetonaphthone 1 by locally isolated Rhodotorula glutinis strains using ram horn peptone (RHP) gave (S)-(-)-1-(1´-naphthyl) ethanol (2), an important pharmaceutical intermediate. R. glutinis strains were isolated from the water of fermented Salix leaves. Optimum fermentation conditions for the production of 2 were 200 rpm, 32 °C, and pH 6.5. The production of 2 with excellent enantiomeric excess (>99%), and good conversion (100%) and yield (78%) under optimum conditions was achieved up to preparative scale via a fermenter. Wide temperature, pH, time, and agitation ranges did not affect the enantiomeric excess (ee) of the bioreduction product. A …
Preparation, Characterization, And Potentiometric Titrations Of Some New Di-[3-(3-Alkyl/Aryl-4,5-Dihydro-1h-1,2,4-Triazol-5-One-4-Yl)-Azomethinphenyl] Isophthalate/Terephthalate Derivatives, Haydar Yüksek, Özlem Gürsoy Kol
Preparation, Characterization, And Potentiometric Titrations Of Some New Di-[3-(3-Alkyl/Aryl-4,5-Dihydro-1h-1,2,4-Triazol-5-One-4-Yl)-Azomethinphenyl] Isophthalate/Terephthalate Derivatives, Haydar Yüksek, Özlem Gürsoy Kol
Turkish Journal of Chemistry
3-Alkyl(Aryl)-4-amino-4,5-dihydro-1H-1,2,4-triazol-5-ones (2) reacted with di-(3-formylphenyl) isophthalate (3) and di-(3-formylphenyl) terephthalate (6) to afford the corresponding 6 novel di-[3-(3-alkyl/aryl-4,5-dihydro-1H-1,2,4-triazol-5-one-4-yl)- azomethinphenyl] isophthalates (4) and 6 novel di-[3-(3-alkyl/aryl-4,5- dihydro-1H-1,2,4-triazol-5-one-4-yl)-azomethinphenyl] terephthalates (7), respectively. The acetylation reactions of compounds 4 and 7 were investigated, and 5 and 8 type compounds were obtained, respectively. The new compounds synthesized were characterized by using IR, ^1H-NMR, ^{13}C-NMR, and UV spectral data together with elemental analysis. In addition, to investigate the effects of solvents and molecular structure upon acidity, compounds 4 and 7 were titrated potentiometrically with tetrabutylammonium hydroxide in 5 non-aqueous solvents (isopropyl alcohol, tert-butyl alcohol, N,N-dimethylformamide, acetone, …
Comparison Of Catalytic Activities Of Carbon Supported Pt And Pt-Ru Catalysts For Methanol Oxidation In Neutral And Basic Media By Cyclic Voltammetry, Abdul Sattar Ali Khan, Riaz Ahmed, Muhammad Latif Mirza
Comparison Of Catalytic Activities Of Carbon Supported Pt And Pt-Ru Catalysts For Methanol Oxidation In Neutral And Basic Media By Cyclic Voltammetry, Abdul Sattar Ali Khan, Riaz Ahmed, Muhammad Latif Mirza
Turkish Journal of Chemistry
The catalytic activities of an equal amount of 3 different carbon supported catalysts containing 10% Pt, 20% Pt + 10% Ru, and 30% Pt were evaluated in neutral and basic media for methanol oxidation by cyclic voltammetry. The prominent oxidation peak for methanol appeared in the forward anodic sweep at around 1.0 V in neutral medium, while in basic medium it appeared at significantly lower potential close to 0.2 V. The peak current for methanol oxidation was higher on a catalyst containing higher Pt loading. The comparison of polarization behavior of 20% Pt + 10% Ru and 30% Pt catalysts …
New Flame-Retardant Poly(Ester-Imide)S Containing Phosphine Oxide Moieties In The Main Chain: Synthesis And Properties, Khalil Faghihi
New Flame-Retardant Poly(Ester-Imide)S Containing Phosphine Oxide Moieties In The Main Chain: Synthesis And Properties, Khalil Faghihi
Turkish Journal of Chemistry
Six new flame-retardant poly(ester-imide)s (9a-f) with high inherent viscosity and containing phosphine oxide moieties in the main chain were synthesized from the polycondensation reaction of N,N-(3,3-diphenylphenyl phosphine oxide) bistrimellitimide diacid chloride (7) with 6 aromatic diols (8a-f) by 2 different methods:--solution and microwave-assisted polycondensation. The results showed that compared to solution polycondensation, the microwave-assisted polycondensation reaction using a domestic microwave oven proceeded rapidly and was completed within about 9-12 min. All of the obtained polymers were fully characterized by means of elemental analysis, viscosity measurement, solubility testing, and FT-IR spectroscopy. Thermal properties and flame retardant behavior of the PEIs (9a-f) …
Hidden Structure Revealed, Minkyu Lee
Hidden Structure Revealed, Minkyu Lee
Theses
This MFA Thesis is based on the aesthetic philosophy that all forms and structures are essentially made from cubes. This premise has inspired and shaped my explorations over the last two years of graduate study. Shape and meaning of ‘cubes’ can be simplified to the smallest molecular units of objects. The geometric forms I construct reflect this. I have mostly created vessel-oriented forms, but now I find that I can also make sculptures that reflect the same point of view. The shape of the earth is a theme and inspiration for this thesis project. Craters, which show their inner side, …
Synthesis And Characterizations Of Some New 4h-1,2,4-Triazole Derivatives, Nesli̇han Demi̇rbaş, Ahmet Demi̇rbaş, Şule Ceylan, Deni̇z Şahi̇n
Synthesis And Characterizations Of Some New 4h-1,2,4-Triazole Derivatives, Nesli̇han Demi̇rbaş, Ahmet Demi̇rbaş, Şule Ceylan, Deni̇z Şahi̇n
Turkish Journal of Chemistry
3-[(5-Amino-1,3,4-thiadiazol-2-yl)methyl]-4-ethoxycarbonylamino-5-alkyl-4H-1,2,4-triazoles (2a,b) were obtained from the reaction of 3-cyanomethyl-5-alkyl-4-ethoxycarbonylamino-4H-1,2,4-triazoles (1a,b) with thiosemicarbazide in the presence of trifluoroacetic acid. The treatment of the obtained compounds (2a,b) with acetic anhydride for 1 h afforded 3-[(5-acetylamino-1,3,4-thiadiazol-2-yl)methyl]-4-ethoxycarbonylamino-5-alkyl-4H-1,2,4-triazoles (3a,b). The synthesis of 4-ethoxycarbonylamino-3-[(2,3-dihydro-1,3-benzoxazol-2-yl)methyl]-5-(4-methylbenzyl)-4H-1,2,4-triazole (4) was performed by the treatment of 3-[(5-acetylamino-1,3,4-thiadiazol-2-yl)methyl]-4-ethoxycarbonylamino-5-(4-methylbenzyl)-4H-1,2,4-triazole (3a) with o-aminophenol under nitrogen atmosphere for 50 h. The reaction of compounds 1a,b with salicylaldehyde in the presence of sodium ethoxide yielded 2-{4-[(ethoxycarbonyl)amino]-5-alkyl-4H-1,2,4-triazol-3-yl}-3-(2-hydroxyphenyl)-acrylonitriles (5a,b). The acetylations of compounds 5a,b with acetic anhydride for 5 h resulted in the formation of 2-{4-[acetyl(ethoxycarbonyl)amino]-5-alkyl-4H-1,2,4-triazol-3-yl}-3-[2-(acetyloxy)phenyl]-acrylic acids (6a,b). On the other hand, the treatment of compounds 5a,b with …
New Polyamides Based On Bis(P-Amidobenzoic Acid)-P-Phenylene Diacrylic Acid And Hydantoin Derivatives: Synthesis And Characterization, Khalil Faghihi
New Polyamides Based On Bis(P-Amidobenzoic Acid)-P-Phenylene Diacrylic Acid And Hydantoin Derivatives: Synthesis And Characterization, Khalil Faghihi
Turkish Journal of Chemistry
Bis(p-amidobenzoic acid)-p-phenylene diacrylic acid (6) as a new monomer containing p-phenylenediacryloyl moiety was synthesized by using a 3-step reaction. At first p-phenylenediacrylic acid (3) was prepared by reaction of terephthal aldehyde (1) with malonic acid (2) in the presence of pyridine, and then diacid 3 was converted to p-phenylenediacryloyl chloride (4) by reaction with thionyl chloride. Finally bis(p-amidobenzoic acid)-p-phenylene diacrylic acid (6) was prepared by the condensation reaction of phenylenediacryloyl chloride (4) with p-aminobenzoic acid (5). Then 6 new polyamides (8a-f) containing p-phenylenediacryloyl and hydantoin moiety in the main chain were prepared by the direct polycondensation reaction of bis(p-amidobenzoic acid)-p-phenylene …
New Polyamides Derived From 2,5-Bis[(4-Carboxyanilino) Carbonyl] Pyridine And Hydantoin Derivatives: Synthesis And Characterization, Khalil Faghihi, Zohreh Mozaffari
New Polyamides Derived From 2,5-Bis[(4-Carboxyanilino) Carbonyl] Pyridine And Hydantoin Derivatives: Synthesis And Characterization, Khalil Faghihi, Zohreh Mozaffari
Turkish Journal of Chemistry
We synthesized 2,5-bis[(4-carboxyanilino) carbonyl] pyridine (4) as a new monomer containing pyridyl moiety by using a 2-step reaction. At first 2,5-pyridine dicarboxylic acid (1) was converted to 2,5-pyridine dicarbonyl dichloride (2). Then, diacid 4 was prepared by a condensation reaction of diacid chloride (2) with p-aminobenzoic acid (3). Then, 6 new polyamides (6a-f) were synthesized through the polycondensation reaction of 2,5-bis[(4-carboxyanilino) carbonyl] pyridine (4) with 6 different derivatives of hydantoins (5a-f) in a medium consisting of N-methyl-2-pyrrolidone, triphenyl phosphite, calcium chloride, and pyridine. The polycondensation reaction produced a series of novel polyamides containing pyridyl moiety in the main chain in …
Partial Regeneration Of Ni-Based Catalysts For Hydrogen Production Via Methane Cracking, Reyyan Koç, Erdoğan Alper, Eric Croiset, Ali Elkamel
Partial Regeneration Of Ni-Based Catalysts For Hydrogen Production Via Methane Cracking, Reyyan Koç, Erdoğan Alper, Eric Croiset, Ali Elkamel
Turkish Journal of Chemistry
Methane cracking has the potential to produce high purity, carbon monoxide-free hydrogen suitable for application in PEM fuel cells. The 2 products of the reaction are molecular hydrogen and solid carbon. The carbon appears in the form of carbon filaments whose growth is hindered by carbon encapsulation leading to total deactivation of the catalyst. Several attempts have been made to regenerate the catalyst, mainly by gasifying the carbon filament in air or steam. Our work on 5-wt% Ni/\gamma-Al_2O_3 indicated that after complete gasification of the carbon the catalyst lost nearly all its activity toward methane cracking. However, if the gasification …
Zinc Perchlorate Hexahydrate Catalyzed Mono- And Bis-Transesterification Of Malonic Esters, Servet Tural
Zinc Perchlorate Hexahydrate Catalyzed Mono- And Bis-Transesterification Of Malonic Esters, Servet Tural
Turkish Journal of Chemistry
Commercially available zinc perchlorate hexahydrate [Zn(ClO_4)_2.6H_2O] was found to be a highly effective catalyst for the transesterification of malonic esters with alcohols. The treatment of methyl-, ethyl-, or \alpha-substituted malonic esters with primary or secondary alcohols in the presence of a catalytic amount of zinc perchlorate results in good to high yields of the corresponding esters (68%-99%). Mono-transesterification products are also obtained in moderate to good yields (22%-42%). The reaction was also carried out with 2-mono- and di-substituted malonic esters, and in the case of 2-mono- and di-substituted malonic esters, the reaction time is, in some cases, shorter, in which …
Characterization And Antimicrobial Activity Of Organotin(Iv) Complexes Of 2-[(2´,6´-Diethylphenylamido)]Benzoates And 3-[(2´,6´-Diethylphenylamido)]Propanoates, Saira Shahzadi, Khadija Shahid, Saqib Ali, Mohammad Bakhtiar
Characterization And Antimicrobial Activity Of Organotin(Iv) Complexes Of 2-[(2´,6´-Diethylphenylamido)]Benzoates And 3-[(2´,6´-Diethylphenylamido)]Propanoates, Saira Shahzadi, Khadija Shahid, Saqib Ali, Mohammad Bakhtiar
Turkish Journal of Chemistry
New organotin(IV) complexes with 2-[(2',6'-diethylphenylamido)] benzoic acid (HL^1) and 3-[(2',6' -diethylphenylamido)]propanoic acid (HL^2) were synthesized by the reaction of di- and triorganotin salts in the presence of triethylamine as base or dioctyltin oxide using a Dean and Stark trap for the removal of azeotropic water. All complexes were characterized by elemental analysis, IR, NMR, and mass spectral studies, and proof that tin-ligand coordination involves only the carboxylate group and complexes show hexa-coordinated geometry in solid state. Multinuclear NMR data show that triorganotin complexes exhibit 4-coordinated geometry while diorganotin complexes show a coordination number greater than 4, probably 5 or 6 …
Synthesis And Characterization Of Novel Polyamide And Polyhydrazides Based On The 6,6´-Disubstituted-2,2´-Bipyridine, Abdurrahman Şengül, Hülya Arslan
Synthesis And Characterization Of Novel Polyamide And Polyhydrazides Based On The 6,6´-Disubstituted-2,2´-Bipyridine, Abdurrahman Şengül, Hülya Arslan
Turkish Journal of Chemistry
The monomers namely 6,6'-dicarbonylchloride-2,2'-bipyridine (1) and 6,6'-dihydrazine-2,2'-bipyridine (2) were synthesized and characterized thoroughly. The polyhydrazides (PHZ1 and PHZ2) were obtained by direct polycondensation of 2 with terephtaloylchloride (TPCl}), and novel polyamide (PA1) by direct polycondensation of 1 with hexametyhlenediamine (HMDA}). Polymers with low PDIs were generated in all cases (PD \sim 1.02-1.3). The polymers were characterized by ^1H and ^{13}C NMR, FT-IR, and Gel Permission Chromatography (GPC).
Synthesis Of Vertilecanin C And Two New Derivatives Of Vertilecanin A Via Nicotinic Acid, Serpi̇l Demi̇rci̇, Süleyman Göksu, Murat Boztaş, Ferhan Tümer, Hasan Seçen
Synthesis Of Vertilecanin C And Two New Derivatives Of Vertilecanin A Via Nicotinic Acid, Serpi̇l Demi̇rci̇, Süleyman Göksu, Murat Boztaş, Ferhan Tümer, Hasan Seçen
Turkish Journal of Chemistry
Vertilecanin C and 2 new phenyl-substituted derivatives of vertilecanin A were synthesized. Lithiation of 5-benzoylpicolinamide with BuLi at -78 °C followed by treatment with methyl bromoacetate gave vertilecanin C [methyl 2-(3-benzoylpicolinamido)acetate], a natural product. Vertilecanin A type phenopicolinic acid derivatives were synthesized starting from nicotinic acid in 4 steps. Chlorination of nicotinic acid with SOCl_2 followed by treatment with anisole in the presence of AlCl_3 gave (4-methoxyphenyl)(pyridin-3-yl)methanone. The Minisci reaction of the ketone afforded 5-(4-methoxybenzoyl)picolinamide. TiCl_4-catalyzed acidic hydrolysis of the picolinamide gave 5-(4-methoxybenzoyl) picolinic acid, from which 5-(hydroxy(4-methoxyphenyl) methyl)picolinic acid was obtained by selective reduction with NaBH_4. The same reaction …
Efficient Synthesis Of Imidazole Derivatives: An Important Synthon For The Preparation Of Biologically Active Compounds, Asghar Davood, Eskandar Alipour, Abbas Shafiee
Efficient Synthesis Of Imidazole Derivatives: An Important Synthon For The Preparation Of Biologically Active Compounds, Asghar Davood, Eskandar Alipour, Abbas Shafiee
Turkish Journal of Chemistry
4(5)-Chloro-imidazole-5(4)-carboxaldehyde derivatives are important precursors for the preparation of biologically active compounds. We developed a simple, novel, and efficient method for the synthesis of these compounds. The chemistry described is amenable to large-scale use and is flexible enough to allow the preparation of analogs.
One-Step Synthesis Of Hyaluronic Acid-Based (Sub)Micron Hydrogel Particles: Process Optimization And Preliminary Characterization, Nurettin Sahiner, Xinqiao Jia
One-Step Synthesis Of Hyaluronic Acid-Based (Sub)Micron Hydrogel Particles: Process Optimization And Preliminary Characterization, Nurettin Sahiner, Xinqiao Jia
Turkish Journal of Chemistry
Hyaluronic acid (HA)-based (sub)micron hydrogel particles were synthesized by crosslinking virgin HA with divinyl sulfone (DVS) in sodium bis(2-ethylhexyl)sulfosuccinate (AOT) reverse micelle systems under basic conditions. Experimental parameters including HA molecular weight, solution concentration, and reaction time were systematically varied in order to obtain well defined hydrogel particles. The use of a cosurfactant, 1-heptanol (1-HP), had a profound effect on the reaction kinetics and the particle morphology. The resulting particles exhibit negative charges on their surfaces. In vitro biocompatibility study indicates that these particles do not cause severe death to the cultured fibroblasts. These HA-based hydrogel particles are promising candidates …
Synthesis And Antimicrobial Activity Of Some 3(2h)-Pyridazinone And 1(2h)-Phthalazinone Derivatives, Deni̇z S. Doğruer, Ti̇jen Önkol, Semi̇ha Özkan, Selda Özgen, M. Fethi̇ Şahi̇n
Synthesis And Antimicrobial Activity Of Some 3(2h)-Pyridazinone And 1(2h)-Phthalazinone Derivatives, Deni̇z S. Doğruer, Ti̇jen Önkol, Semi̇ha Özkan, Selda Özgen, M. Fethi̇ Şahi̇n
Turkish Journal of Chemistry
Some 3(2H)-pyridazinone and 1(2H)-phthalazinone derivatives were synthesized. The structures of these new compounds were confirmed by IR, ^1H-NMR, mass spectrum, and elemental analysis. The synthesized compounds were evaluated for their antibacterial activity against various gram-positive and gram-negative strains of bacteria and their clinical isolates and for their antimycobacterial activity against M. tuberculosis H37Rv. The results showed that the synthesized compounds were generally active against B. subtilis and its clinical isolate. Among the target compounds, compound 14c exhibited the best antibacterial activity, with a MIC value of 15.62 \mu g/mL against B. subtilis. Compound 15e had the highest antimycobacterial activity.