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Synthesis, Characterization, Crystal Structures, And Antibacterial Activity Of Some New 1-(3,4,5-Trimethoxybenzoyl)-3-Aryl Thioureasreas, Aamer Saeed, Rasheed Ahmad Khera, Naeem Abbas, Muhammad Latif, Imran Sajid, Ulrich Flörke
Synthesis, Characterization, Crystal Structures, And Antibacterial Activity Of Some New 1-(3,4,5-Trimethoxybenzoyl)-3-Aryl Thioureasreas, Aamer Saeed, Rasheed Ahmad Khera, Naeem Abbas, Muhammad Latif, Imran Sajid, Ulrich Flörke
Turkish Journal of Chemistry
Synthesis of some novel 1-(3,4,5-trimethoxy)benzoyl-3- arylthiourea derivatives (1a-o) was accomplished in 2 steps. The synthetic route involves the reaction of 1-(3,4,5-trimethoxy)benzoyl chloride with potassium thiocyanate in 1:1 molar ratio in acetone to afford the corresponding isothiocyante followed by treatment with suitably substituted anilines. The structures of the products were established by elemental analyses, IR, ^1H- and ^{13}C-NMR, and mass spectroscopy and for 1b and 1m from single crystal X-ray diffraction data. All of the synthesized compounds (1a-o) were screened for antibacterial activity against gram positive and gram negative bacterial strains and were found to exhibit low activity towards the tested …
Molecular Recognition Of Aromatic Amines By Coumarin Substituted Azacrown Ether, Hiten Mehta, Harjinder Kaur, Shobhana Menon
Molecular Recognition Of Aromatic Amines By Coumarin Substituted Azacrown Ether, Hiten Mehta, Harjinder Kaur, Shobhana Menon
Turkish Journal of Chemistry
New chromogenic azacrown ether N[7-hydroxy-4-methyl-coumarin-8-methylene]-4-azadibenzo-18-crownether (HMCMADCE) was synthesised through the condensation reaction of 4-azadibenzo-18-crown- 6ether, 4-methyl,7-hydroxy coumarin and formaldehyde was used to investigate its behaviour towards the aromatic amines. All the aromatic primary amines gave specific colours in aqueous medium. The functional group recognition behaviour is further extended to study the estimation of the aromatic primary amine in commercial drug samples. The amines can be estimated in the presence of several functional groups like phenolic-OH, secondary and tertiary aromatic amines as well as aliphatic amines.
Synthesis Of Some New Biheterocyclic Triazole Derivatives And Evaluation Of Their Antimicrobial Activity, Hakan Bektaş, Ahmet Demi̇rbaş, Nesli̇han Demi̇rbaş, Şengül Alpay Karaoğlu
Synthesis Of Some New Biheterocyclic Triazole Derivatives And Evaluation Of Their Antimicrobial Activity, Hakan Bektaş, Ahmet Demi̇rbaş, Nesli̇han Demi̇rbaş, Şengül Alpay Karaoğlu
Turkish Journal of Chemistry
2-{3-(4-Substitutedbenzyl)-4-[2-(1H-indol-3-yl)ethyl]-5-oxo-4,5- dihydro-1H-1,2,4-triazol-1-yl}-N'-(aryl-methylene)acetohydrazides (5a-g), 4-amino-2-{-(4-substitutedbenzyl)-5-oxo-4,5-dihydro-1H-1,2,4-triazol- 1-yl}-N'-(arylmethylene)acetohydrazides (6a,b), and 4-[2-(1H-indol- 3-yl)ethyl]-5-(4-substitutedbenzyl)-2-{5-(phenylamino)-1,3,4-thiadiazol- 2-yl]methyl}-2,4-dihydro-3H-1,2,4-triazol-3-ones (8a,b) were synthesized starting from 4-alkyl-5-(4-substitutedbenzyl)-2,4-dihydro- 3H-1,2,4-triazol-3-ones (2a-c) by several steps and their structures were well characterized by elemental analyses, IR, ^1H-NMR, ^{13}C-NMR, and mass spectral studies. They were also screened for their microbial activities. The obtained antimicrobial activity results revealed that 12 among the 24 compounds tested displayed variable growth inhibition effects on the tested gram-positive and gram-negative bacterial strains. None of the compounds showed antifungal activity against yeast-like fungi.
Chelating Agent Free Solid Phase Extraction (Caf-Spe) Method For Separation And/Or Preconcentration Of Iron(Iii) Ions, Özcan Yalçinkaya, Orhan Murat Kalfa, Ali̇ Rehber Türker
Chelating Agent Free Solid Phase Extraction (Caf-Spe) Method For Separation And/Or Preconcentration Of Iron(Iii) Ions, Özcan Yalçinkaya, Orhan Murat Kalfa, Ali̇ Rehber Türker
Turkish Journal of Chemistry
This paper presents a chelating agent free solid phase extraction (CAF-SPE) method for the separation and/or preconcentration of trace iron(III) ions. This method is based on the sorption of Fe(III) ions without using any chelating agent onto Amberlyst 36 resin. A good relative standard deviation (3%), high recovery (>95%), high enrichment factor (100), and low detection limit (0.32 \mu g L^{-1}) were obtained. The adsorption capacity of resin was 117 mg g^{-1} for iron(III). The method was applied for the determination of iron various in water and commercial tea bag samples. The accuracy of the method was confirmed by …
Highly Stereoselective And Efficient Synthesis Of The Dopa Analogue In Pepticinnamin E Via Enantioselective Hydrogenation Of Dehydroamino Acids, Dequn Sun
Turkish Journal of Chemistry
An efficient and new method was developed to prepare the dopa analogue 11 in natural pepticinnamin via catalytic hydrogenation of dehydroamino acids (DDAA) with a good yield and ee. Product 11 is a key intermediate towards the total synthesis of pepticinnamin E and its analogues.
Synthesis And Antimicrobial Activity Of N-Alkyl Substituted P-Methyl (E)-3- And 4-Azachalconium Bromides, Nuretti̇n Yayli, Gülbi̇n Misir, Nuran Yayli, Ahmet Yaşar, Emi̇ne Demi̇r, Zi̇hni̇ Demi̇rbağ
Synthesis And Antimicrobial Activity Of N-Alkyl Substituted P-Methyl (E)-3- And 4-Azachalconium Bromides, Nuretti̇n Yayli, Gülbi̇n Misir, Nuran Yayli, Ahmet Yaşar, Emi̇ne Demi̇r, Zi̇hni̇ Demi̇rbağ
Turkish Journal of Chemistry
Twenty new N-alkyl substituted p-methyl (E)-3- and 4-azachalcones (1a-j, 2a-j){3-[(1E)-3-(4-methylp-henyl)-3- oxoprop-1-en-1-yl]-1-alkyl (C_{5-12,_{14-15) pyridinium bromides (1a-j) and 4-[(1E)-3-(4-methylp-henyl)-3-oxoprop-1-en-1-yl]-1-alkyl (C_{5-12,_{14-15) pyridinium bromides (2a-j)} were synthesized and tested for antimicrobial activities against Staphylococcus aureus, Staphylococcus epidermidis, Bacillus subtilis, Enterococcus faecalis, Proteus vulgaris, and Escherichia coli. They showed good antimicrobial activity especially against the gram-positive bacteria tested with minimal inhibitory concentration (MIC) values less than 4.7 \mu g/mL in most cases. The optimum length of the alkyl chain for better and broader activity is situated in the range of 8-12 carbon atoms in the series of compounds 1a-j, 2a-j. The non-alkylated compounds 1-2 were …
Performance Evaluation Of Platinum-Based Catalysts For The Development Of Proton Exchange Membrane Fuel Cells, Abdul Sattar Ali Khan, Riaz Ahmed, Muhammad Latif Mirza
Performance Evaluation Of Platinum-Based Catalysts For The Development Of Proton Exchange Membrane Fuel Cells, Abdul Sattar Ali Khan, Riaz Ahmed, Muhammad Latif Mirza
Turkish Journal of Chemistry
Platinum-based catalysts are considered the most efficient catalysts for triggering electrochemical reactions in proton exchange membrane (PEM) fuel cells. In the present study, commercial catalysts containing 10% and 30% Pt supported on Vulcan XC-72 carbon were studied to assess their performance in PEM fuel cells. Both catalysts consisted of Pt particles of almost the same size. The utility of these catalysts in PEM fuel cells was studied by finding the real surface area and rate of electro-oxidation of methanol in 0.5 M H_2SO_4 by using cyclic voltammetry. The methanol oxidation reaction was used for characterization of catalysts of PEM fuel …
Synthesis, Structural Determination, And Biological Activity Of New 7-Hydroxy-3-Pyrazolyl-4h-Chromen- 4-Ones And Their O-\Beta-D-Glucosides, Kishor Hatzade, Vijay Taile, Pravin Gaidhane, Vishwas Ingle
Synthesis, Structural Determination, And Biological Activity Of New 7-Hydroxy-3-Pyrazolyl-4h-Chromen- 4-Ones And Their O-\Beta-D-Glucosides, Kishor Hatzade, Vijay Taile, Pravin Gaidhane, Vishwas Ingle
Turkish Journal of Chemistry
A convenient route to synthesize some new medicinally important 7-hydroxy-3-pyrazolyl chromones (3a-i) is described. The interaction of 7-hydroxy-3-formyl chromone (1) with various substituted acetophenones and further cyclization with hydrazine hydrate in an aprotic solvent followed by condensation with 2, 3, 4, 6-tetra-o-acetyl-\alpha-dglucopyranosyl bromide afforded 2, 3, 4, 6-tetra-o-acetyl-\beta-d-glucopyranosyloxy-3-(3-aryl-1H-pyrazol-5- yl)-4H-chromen-4-ones (4a-i). Later deacetylation with anhydrous zinc acetate in methanol gave 7-o-\beta-d-glucopyranosyloxy-3-(3-aryl- 1H-pyrazol-5-yl)-4H-chromen-4-ones (5a-i). These compounds were evaluated for their in vitro antimicrobial and anti-oxidant activity. The structures of these newly synthesized o-glucosides were established by IR, NMR, mass spectra, elemental analysis, and chemical analysis.
Composition Of The Essential Oils Of Pinus Nigra Arnold From Turkey, Ekrem Sezi̇k, Osman Üstün, Bülent Demi̇rci̇, Kemal Hüsnü Can Başer
Composition Of The Essential Oils Of Pinus Nigra Arnold From Turkey, Ekrem Sezi̇k, Osman Üstün, Bülent Demi̇rci̇, Kemal Hüsnü Can Başer
Turkish Journal of Chemistry
Essential oil composition of the needles of Pinus nigra Arnold collected from different localities in Turkey was investigated by GC and GC/MS. The main components in the oils were \alpha-pinene, \beta-pinene, \beta-caryophyllene, and germacrene D.
Isolation And Identification Of A New Acetildenafil Analogue Used To Adulterate A Dietary Supplement: Dimethylacetildenafil, Ali̇ Hakan Göker, Maksut Coşkun, Mehmet Alp
Isolation And Identification Of A New Acetildenafil Analogue Used To Adulterate A Dietary Supplement: Dimethylacetildenafil, Ali̇ Hakan Göker, Maksut Coşkun, Mehmet Alp
Turkish Journal of Chemistry
A new sildenafil analogue was found to have been added illegally to a dietary supplement marketed for the enhancement of sexual function. The structure was determined as 5-(2-ethoxy-5- {[4-(3,5-dimethyl)piperazin-1-yl]-acetyl}phenyl)-1,6-dihydro-1-methyl-3- propyl-7H-pyrazolo [4,3-d]pyrimidin-7-one. Owing to the inclusion of a dimethyl group in acetildenafil, the detected compound was called dimethylacetildenafil. The sample was purified with column chromatography. The IR, LC/MS (ESI), and completely assigned NMR data of dimethylacetildenafil are reported for the first time. The structure was compared with that of acetildenafil and the results showed that the ethyl substitution at the 4-position of the piperazine ring had been replaced by a 3,5-dimethyl …
Simultaneous Determination Of Cu(Ii) And Pd(Ii) As 4-Phenylpiperazinecarbodithioate Complex Using H-Point Standard Addition Method And Derivative Spectrophotometry, Varinder Kaur, Ashok Kumar Malik, Neelam Verma
Simultaneous Determination Of Cu(Ii) And Pd(Ii) As 4-Phenylpiperazinecarbodithioate Complex Using H-Point Standard Addition Method And Derivative Spectrophotometry, Varinder Kaur, Ashok Kumar Malik, Neelam Verma
Turkish Journal of Chemistry
A new, simple, inexpensive, and sensitive method for the simultaneous spectrophotometric determination of Cu(II) and Pd(II) by H-point standard addition method and derivative spectrophotometry is described. 4- Phenylpiperazinecarbodithioate (PPDTC) in an anionic micellar solution of SLS was used as a reagent at pH 4. The experimental parameters, such as pH, type of surfactant, concentration of reagent, and surfactant used, were optimized to minimize the errors. The linear ranges of the method were 0.1-10 and 0.1-11 \mu g mL^{-1} for Cu(II) and Pd(II), respectively. The results of applying H-point standard addition and fourth derivative spectrophotometry showed that Cu(II) and Pd(II) can …
Synthesis And Characterization Of Non-Symmetric Tetradentate Complexes Of Zn(Ii), Co(Ii), And Cu(Ii), Maryam Lashanizadegan, Shima Seraj
Synthesis And Characterization Of Non-Symmetric Tetradentate Complexes Of Zn(Ii), Co(Ii), And Cu(Ii), Maryam Lashanizadegan, Shima Seraj
Turkish Journal of Chemistry
The non-symmetrical tetradentate Schiff-base H_2L was obtained using the half-unit N-(1-hydroxy-2-acetophenone)-1-amino- 2-phenyleneimine (HL) with 2-hydroxyl-1-naphthaldehyde. ZnL, CoL, and CuL complexes were prepared and characterized by ^1H-NMR, IR, electronic, and atomic absorption spectra. The single crystal X-ray structure of CuL was determined. Crystal data for CuL are triclinic space group P-1, a = 8.3933 (17) Å, b = 11.197 (2) Å, c = 13.381 (3) Å, \alpha = 95.29 (3)°, \beta = 94.37 (3)°, \gamma = 95.82 (3)°, and z = 2.
Direct Reductive Amination Of Carbonyl Compounds Using Sodium Borohydride-Silica Chloride, Heshmatollah Alinezhad, Mahmood Tajbakhsh, Neda Hamidi
Direct Reductive Amination Of Carbonyl Compounds Using Sodium Borohydride-Silica Chloride, Heshmatollah Alinezhad, Mahmood Tajbakhsh, Neda Hamidi
Turkish Journal of Chemistry
A simple and convenient procedure for reductive amination of aldehydes and ketones using sodium borohydride in the presence of silica chloride as an active, inexpensive, recoverable, and recyclable catalyst is described. The reactions were carried out with equimolar amounts of amine and carbonyl compound using silica chloride-sodium borohydride in THF at room temperature.
Synthesis And Antimicrobial Activities Of 2-(5-Mercapto)-1,3-Oxadiazol-2-Ylmethyl-1,2,4-Triazol-3-One Derivatives, Nesli̇han Demi̇rbaş, Ahmet Demi̇rbaş, Hakan Bektaş, Şengül Alpay Karaoğlu, Deni̇z Şahi̇n
Synthesis And Antimicrobial Activities Of 2-(5-Mercapto)-1,3-Oxadiazol-2-Ylmethyl-1,2,4-Triazol-3-One Derivatives, Nesli̇han Demi̇rbaş, Ahmet Demi̇rbaş, Hakan Bektaş, Şengül Alpay Karaoğlu, Deni̇z Şahi̇n
Turkish Journal of Chemistry
The synthesis of 4-amino-2-[(5-mercapto-1,3,4-oxadiazol-2- yl)methyl]-5-(4-methylphenyl)-2,4-dihydro-3H-1,2,4-triazol-3-one (2) and 4-amino-2-[(4-amino-5-mercapto-4H-1,2,4-triazol-3-yl)methyl]- 5-(4-methylphenyl)-2,4-dihydro-3H-1,2,4-triazol-3-one (5) was performed starting from 2-[4-amino-3-(4-methylphenyl)-5-oxo-4,5- dihydro-1H-1,2,4-triazol-1-yl]acetohydrazide (1). The treatment of 2 and 5 with 4-fluorobenzaldehyde (for 8) or salicylaldehyde (for 6) afforded the corresponding Schiff bases (6 and 8). The condensation of 5 with phenacyl bromide produced 4-amino-5-(4-methylphenyl)-2- [(6-phenyl-7H-[1,2,4]triazolo[3,4-b][1,3,4]thiadiazin-3-yl)methyl]- 2,4-dihydro-3H-1,2,4-triazol-3-one (7). The alkylation of 2 and 8 was carried out by using methyl iodide in basic media. Compounds 3 and 10a,b were prepared by aminoalkylation of 2 and 8 with 4-fluorophenyl piperazine, morpholine, or 4-methyl piperazine in the presence of formaldehyde. The synthesized compounds were screened for their antimicrobial activities …
Picolyl Substituted N-Heterocyclic Carbene/Palladium Catalyzed Heck Reactions, Murat Yi̇ği̇t, Beyhan Yi̇ği̇t, İsmai̇l Özdemi̇r, Engi̇n Çeti̇nkaya
Picolyl Substituted N-Heterocyclic Carbene/Palladium Catalyzed Heck Reactions, Murat Yi̇ği̇t, Beyhan Yi̇ği̇t, İsmai̇l Özdemi̇r, Engi̇n Çeti̇nkaya
Turkish Journal of Chemistry
Novel 1,3-dialkylimidazolinium and 1,3- dialkyltetrahydropyrimidinium hexafluorophosphate salts as N-heterocyclic carbene precursors were prepared by reacting N,N'-dialkylethandiamine or N,N'-dialkylpropandiamine, triethyl orthoformate, and ammonium hexafluorophosphate. The salts were characterized spectroscopically and tested in homogeneous Heck reactions.
Convenient Synthesis Of Monomeric Steroids From Steroidal Oxalate Dimers Using Flash Vacuum Pyrolysis (Fvp), Lutfun Nahar, Alan Turner, Satyajit Sarker
Convenient Synthesis Of Monomeric Steroids From Steroidal Oxalate Dimers Using Flash Vacuum Pyrolysis (Fvp), Lutfun Nahar, Alan Turner, Satyajit Sarker
Turkish Journal of Chemistry
Flash vacuum pyrolysis (FVP) or thermolysis (FVT), an environmentally friendly method for studying organic reaction mechanisms as well as synthesis, was applied to a series of oxalate dimers (1, 3, 5, 7, 9, 11, 13, and 15) to synthesise monomeric enes, dienes, and a triene (2, 4, 6, 8, 10, 12, 14, and 16). All steroidal monomers were identified by spectroscopic means.
Synthesis, Characterisation, And Structural Elucidation By Spectral Investigation (Ft-Ir, Multinuclear Nmr, Mass Spectrometry) Of Biologically Active Organotin(Iv) Compounds Containing Germanium, Muhammad Kaleem Khosa, Muhammad Mazhar, Saqib Ali, Sarim Dastgir
Synthesis, Characterisation, And Structural Elucidation By Spectral Investigation (Ft-Ir, Multinuclear Nmr, Mass Spectrometry) Of Biologically Active Organotin(Iv) Compounds Containing Germanium, Muhammad Kaleem Khosa, Muhammad Mazhar, Saqib Ali, Sarim Dastgir
Turkish Journal of Chemistry
A new series of di and tri-organotin(IV) compounds containing germanium with the general formula R_{4-n}SnL_n was synthesised by reaction of 3-triphenylgermanyl-3,3-dimethylpropionic acid with organotin(IV) oxides and organotin(IV) chloride in 2:1 and 1:1 molar ratio, respectively, where R~=~CH_3, C_2H_5, n-C_4H_9, n-C_8H_{17}, and C_6H_5 n = 1 or 2 and L~=~triphenylgermanyl acid anion (GeC_{23} H_{23} O_2^-). These compounds were characterised by elemental analyses, FT-IR, multinuclear NMR (^1H, ^{13}C, ^{119}Sn), and mass spectrometry. The geometry around the tin atom was determined and compared in both solution and solid states. The spectroscopic results indicated that all the diorganotin(IV) compounds containing germanium possess trigonal-bipyramidal structures …
A Theoretical Study Of The Effects Of Polar Substitution On The Activation Barriers For Internal Rotation Around The C-N Bond In P-Substituted Nitrosobenzenes: Comparison Of Dft And Mp2 Calculations, Şafak Özhan Kocakaya, Necmetti̇n Pi̇ri̇nççi̇oğlu
A Theoretical Study Of The Effects Of Polar Substitution On The Activation Barriers For Internal Rotation Around The C-N Bond In P-Substituted Nitrosobenzenes: Comparison Of Dft And Mp2 Calculations, Şafak Özhan Kocakaya, Necmetti̇n Pi̇ri̇nççi̇oğlu
Turkish Journal of Chemistry
The activation barriers for internal rotation around the C-N bond in p-substituted nitrosobenzenes were calculated using the density functional theory (DFT) and second-order Møller-Plesset (MP2) methods with the 6-31+g(d) basis set. The polarisable continuum model (PCM) was used to model the solvent effect. An explicit water molecule was also introduced to form a hydrogen bond with the nitrosogroup and its effect on the barrier was studied by DFT. The barriers were well-correlated with Hammett sigma^+ rather than sigma values, meaning a strong resonance effect. The MP2 method produces better and comparable results with the few available experimental values.
Comparative Kinetic Studies On The Alkaline Hydrolysis Of Halogen Substituted Isocoumarins, Hafiz Badaruddin Ahmad, Muhammad Aslam Malana, Muhammad Yousaf, Muhammad Rehan, Mazhar Abbas
Comparative Kinetic Studies On The Alkaline Hydrolysis Of Halogen Substituted Isocoumarins, Hafiz Badaruddin Ahmad, Muhammad Aslam Malana, Muhammad Yousaf, Muhammad Rehan, Mazhar Abbas
Turkish Journal of Chemistry
Kinetics of the hydrolysis of 3-(2'-chloro-6'-fluorobenzyl) isocoumarin (1), 3-(4'-fluorophenyl)isocoumarin (3), 3-(2'- fluorophenyl)isocoumarin (5), 3-(2'-chlorophenyl)isocoumarin (7), and 3-(4'-chlorophenyl)isocoumarin (9) were studied spectrophotometrically in the presence of aqueous solution of potassium hydroxide. The rates of hydrolyses for these isocoumarins were compared. The data for isocoumarin (1) were further investigated to probe the reaction mechanism. The dependence of pseudo-first order rate constant k_{obs} on hydroxide ion concentration is fitted by the expression k_{obs} = k_o + k_1[OH] + k_2 [OH]^2, showing the formation of monoanionic and dianionic tetrahedral intermediates during the course of reaction. The magnitude of k_o shows significant participation of solvent …
A Simple And Efficient One-Pot Multicomponent Synthesis Of \Beta-Acetamido Carbonyl Compounds With Zn(Hso_4)_2 And Co(Hso_4)_2 As Catalysts, Ahmad Reza Momeni, Maryam Sadeghi, Motahareh Hadizadeh
A Simple And Efficient One-Pot Multicomponent Synthesis Of \Beta-Acetamido Carbonyl Compounds With Zn(Hso_4)_2 And Co(Hso_4)_2 As Catalysts, Ahmad Reza Momeni, Maryam Sadeghi, Motahareh Hadizadeh
Turkish Journal of Chemistry
Zn(HSO_4)_2 and Co(HSO_4)_2 has been used as efficient catalysts for the preparation of \beta-acetamido carbonyl compounds by Dakin-West reaction.
A Facile Method For The Preparation Of Poly(4-Vinylpyridine) Nanoparticles And Their Characterization, Nurettin Sahiner
A Facile Method For The Preparation Of Poly(4-Vinylpyridine) Nanoparticles And Their Characterization, Nurettin Sahiner
Turkish Journal of Chemistry
Submicron size particles were synthesized from 4-vinylpyridine (4-VP) using an oil-in-water emulsion system. Divinyl benzene (DVB) and ethylene glycol dimethacrylate (EGDMA) were utilized as crosslinkers for the synthesis of p(4-VP) hydrogel nanoparticles in sodium dodecyl sulfate (SDS) surfactant systems. Characterization of the particles was made by transmission electron microscopy (TEM) and dynamic light scattering (DLS) methods. To render a positive charge, p(4-VP) particles were reacted with 1-bromo butane (1-BB).
Voltammetric Determination Of Ascorbic Acid And Dopamine Simultaneously At A Single Crystal Au(111) Electrode, Zekerya Dursun, Levent Peli̇t, Isao Taniguchi
Voltammetric Determination Of Ascorbic Acid And Dopamine Simultaneously At A Single Crystal Au(111) Electrode, Zekerya Dursun, Levent Peli̇t, Isao Taniguchi
Turkish Journal of Chemistry
A single-crystal Au(111) electrode was used for the simultaneous determination of dopamine (DA) and ascorbic acid (AA) in a phosphate buffer solution at pH 6.9. The single-crystal Au(111) electrode displayed excellent electrocatalytic activity for DA and AA oxidation in comparison to a Au disk electrode. Although the anodic peaks of both reagents overlapped on the Au disk electrode, the anodic peak potentials of DA and AA in their mixture were well separated since the peak potential of AA was shifted to more negative values by cyclic and differential pulse voltammetry. The oxidation peak current increased linearly with the concentration of …
A Simple Spectrophotometric Method For The Determination Of Iron(Ii) Aqueous Solutions, M. Jamaluddin Ahmed, Uttam Kumer Roy
A Simple Spectrophotometric Method For The Determination Of Iron(Ii) Aqueous Solutions, M. Jamaluddin Ahmed, Uttam Kumer Roy
Turkish Journal of Chemistry
An ultra-sensitive and highly selective non-extractive spectrophotometric method is presented for the rapid determination of iron(II) at trace levels using 2', 3, 4', 5, 7-Pentahydroxyflavone (morin) as a new spectrophotometric reagent in slightly acidic solution (0.0001-0.0002 M H_2SO_4). The reaction is instantaneous and absorbance remains stable for over 24 h (\lambda_{max} = 415 nm). The molar absorptivity was found to be 6.85 \times 10^4 L mol^{-1} cm^{-1}. Linear calibration graphs were obtained for 0.01-10 \mu g mL^{-1} of Fe^{II}. The stoichiometric composition of the chelate is 1:2 (Fe:morin). Large excesses of over 50 cations, anions, and complexing agents (e.g., tartrate, …
Preparation And Characterization Of Magnetic Chitosan Nanospheres, Doina Hritcu, Marcel I. Popa, Nuculina Popa, Vasile Badescu, Vera Balan
Preparation And Characterization Of Magnetic Chitosan Nanospheres, Doina Hritcu, Marcel I. Popa, Nuculina Popa, Vasile Badescu, Vera Balan
Turkish Journal of Chemistry
A method for the preparation of magnetite/chitosan composite nanoparticles was developed. Colloidal magnetite particles (Fe_3O_4 produced by co-precipitation and stabilized in suspension by adding a non-ionic surfactant (Pluronic F127) were subsequently covered with a layer of chitosan (CS) prepared by ionotropic gelation using sodium tripolyphosphate (STPP) as a crosslinking agent. The products were characterized in terms of the following parameters: size distribution and \zeta-potential (by laser diffraction analysis), surface morphology (TEM), composition (FTIR, elemental analysis), magnetic properties (magnetic susceptibility analysis), and concentration of surface functional groups (potentiometric titration). The synthesis parameters were optimized for obtaining uniformly distributed colloidally stable, biocompatible …
Synthesis And Antimicrobial Activity Of Dinaphtho[2,1-B]Furan-2-Yl-Methanone And Their Oxime Derivatives, Cumhur Kirilmiş, Murat Koca, Süleyman Servi̇, Seher Gür
Synthesis And Antimicrobial Activity Of Dinaphtho[2,1-B]Furan-2-Yl-Methanone And Their Oxime Derivatives, Cumhur Kirilmiş, Murat Koca, Süleyman Servi̇, Seher Gür
Turkish Journal of Chemistry
The reaction of 2-hydroxy-1-naphthaldehyde with 1,3-dichloroacetone and potassium carbonate was used to prepare dinaphtho[2,1-b]furan-2-yl-methanone (1) as starting reagents. In order to obtain dinaphtho[2,1-b]furan-2-yl-methanole (2), compound 1 was reduced with NaBH_4. N-oxime derivative of this compound (3) was synthesized by the reaction of the compound 1 with hydroxylamine. Alkyl and acyl substituted N-oxime ethers (4-11) were obtained by the reaction compound 3 with various halogen containing compounds. Compound 12 was obtained by reflux of the compound 11 with hydrazine monohydrate in ethanol. Compound 13 was synthesized by the reaction of the compound 11 with NaOH. The synthesized compounds were tested for …
Electrochemical And Optical Properties Of An Azo Dye Based Conducting Copolymer, Ati̇lla Ci̇haner, Fati̇h Algi
Electrochemical And Optical Properties Of An Azo Dye Based Conducting Copolymer, Ati̇lla Ci̇haner, Fati̇h Algi
Turkish Journal of Chemistry
The electrochemical and optical properties of a novel conducting copolymer called poly(2,5'-dimethyl-[4-(2,5-di-thiophen- 2-yl-pyrrol-1-yl)-phenyl]azobenzene-co-(3,4-ethylenedioxythiophene)) (poly(1-co-EDOT)) are reported. Electrochemically synthesized poly(1-co-EDOT) based on the azo dye has a well-defined and reversible redox couple (0.37 V vs. Ag/AgCl) with good cycle stability. The copolymer film exhibits high conductivity (13 S/cm) as well as electrochromic behavior (magenta when neutralized and transmissive sky blue when oxidized). Furthermore, electro-optically active copolymer film has a low band gap of 1.79 eV with a \pi-\pi* transition at 555 nm.
Partial Regeneration Of Ni-Based Catalysts For Hydrogen Production Via Methane Cracking Part Ii: Modeling And Optimization, Reyyan Koç, Erdoğan Alper, Eric Croiset, Ali Elkamel
Partial Regeneration Of Ni-Based Catalysts For Hydrogen Production Via Methane Cracking Part Ii: Modeling And Optimization, Reyyan Koç, Erdoğan Alper, Eric Croiset, Ali Elkamel
Turkish Journal of Chemistry
High purity, carbon monoxide-free hydrogen and filamentous carbon can be produced by thermo-catalytic cracking of methane. Carbon filaments continue to grow until the catalyst deactivates because of carbon encapsulation. Regeneration of catalyst is important to maintain a continuous process. Our work on optimization of the partial regeneration method showed that activity of the catalyst can be sustained for longer times by gasifying not all but some extent of the deposited carbon. In the previous work, a kinetic model was developed to be able to understand the reaction mechanism of deactivation of fresh catalyst at the molecular level. The objective of …
Three-Component Process For The Synthesis Of Some Pyrrole Derivatives Under Microwave Irradiation, Farhad Hatamjafari, Nasser Montazeri
Three-Component Process For The Synthesis Of Some Pyrrole Derivatives Under Microwave Irradiation, Farhad Hatamjafari, Nasser Montazeri
Turkish Journal of Chemistry
We report a short and efficient 3-component reaction for synthesis of a series of [1,2-b]pyrrole derivatives from ninhydrin, alkyl propiolates, and simple primary amines under solvent free and microwave irradiation. This method provides a new route to produce pyrrole derivatives in good to excellent yields.
Synthesis, Characterization, And Antibacterial Activity Of Some Transition Metals With The Schiff Base N-(2-Furanylmethylene)-3-Aminodibenzofuran, Aurora Reiss, Stelian Florea, Theodor Caproiu, Nicolae Stanica
Synthesis, Characterization, And Antibacterial Activity Of Some Transition Metals With The Schiff Base N-(2-Furanylmethylene)-3-Aminodibenzofuran, Aurora Reiss, Stelian Florea, Theodor Caproiu, Nicolae Stanica
Turkish Journal of Chemistry
This paper presents the structure and antibacterial properties of some complexes of Co(II), Ni(II), Cu(II), Zn(II), Cd(II), and Hg(II) with a new Schiff base N-(2-furanylmethylene)-3- aminodibenzofuran. The structure of each complex was characterized by spectroscopic methods (IR, UV-Vis, ^1H-NMR, and ESR), conductometric and magnetic data, and thermogravimetric and elementary analysis. According to these data, we propose an octahedral geometry for Co(II), Ni(II), and Cu(II) complexes, and a tetrahedral geometry for Zn(II), Cd(II), and Hg(II) complexes. Antibacterial activity of the ligand and its complexes was tested against selected bacteria. The ligand and all the complexes possess antimicrobial activity, and antimicrobial activity …