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Articles 6721 - 6750 of 10319
Full-Text Articles in Physical Sciences and Mathematics
On Injective And Subdirectly Irreducible S-Acts Over Left Zero Semigroups, Gholamreza Moghaddasi
On Injective And Subdirectly Irreducible S-Acts Over Left Zero Semigroups, Gholamreza Moghaddasi
Turkish Journal of Mathematics
The aim of this paper is to characterize subdirectly irreducible S-acts over left zero semigroups. Also we compute the number of such acts and specify cogenerators acts over left zero semigroups. To do these we first take another look at the description of injective hulls of the separated S-acts over left zero semigroups.
L^P Regularity Of Some Weighted Bergman Projections On The Unit Disc, Yunus Ergi̇n Zeytuncu
L^P Regularity Of Some Weighted Bergman Projections On The Unit Disc, Yunus Ergi̇n Zeytuncu
Turkish Journal of Mathematics
We show that weighted Bergman projections, corresponding to weights of the form M(z)(1- z ^2)^\alpha, where \alpha > -1 and M(z) is a radially symmetric, strictly positive and at least C^2 function on \overline{D}, are L^p regular.
Superinjective Simplicial Maps Of The Complexes Of Curves On Nonorientable Surfaces, Elmas Irmak
Superinjective Simplicial Maps Of The Complexes Of Curves On Nonorientable Surfaces, Elmas Irmak
Turkish Journal of Mathematics
We prove that each superinjective simplicial map of the complex of curves of a compact, connected, nonorientable surface is induced by a homeomorphism of the surface, if (g, n) \in {(1, 0), (1, 1), (2, 0), (2, 1), (3, 0)} or g + n \geq 5, where g is the genus of the surface and n is the number of the boundary components.
Simultaneous Proximinality Of Vector Valued Function Spaces, Mona Khandaqji, Fadi Awawdeh, Jamila Jawdat
Simultaneous Proximinality Of Vector Valued Function Spaces, Mona Khandaqji, Fadi Awawdeh, Jamila Jawdat
Turkish Journal of Mathematics
A characterization of best simultaneous approximation of Köthe spaces of vector-valued functions is given. This characterization is a generalization of some analogous theorems for Orlicz Bochner spaces.
Generalization Of Some Properties Of Banach Algebras To Fundamental Locally Multiplicative Topological Algebras, Ali Zohri, Ali Jabbari
Generalization Of Some Properties Of Banach Algebras To Fundamental Locally Multiplicative Topological Algebras, Ali Zohri, Ali Jabbari
Turkish Journal of Mathematics
In this article we generalized some properties of Banach algebras, to a new class of topological algebras namely fundamental and fundamental locally multiplicative topological algebras (abbreviated by FLM). Also the new notion of sub-multiplicatively metrizable topological algebra is given and some well known spectral properties of Banach algebras are generalized to such kind of algebras.
Hypercyclic Tuples Of The Adjoint Of The Weighted Composition Operators, Rahmat Soltani, Bahram Khani Robati, Karim Hedayatian
Hypercyclic Tuples Of The Adjoint Of The Weighted Composition Operators, Rahmat Soltani, Bahram Khani Robati, Karim Hedayatian
Turkish Journal of Mathematics
An n-tuple of commuting operators, (T_1,T_2,...,T_n) on a Hilbert space \cal H is said to be hypercyclic, if there exists a vector x \in \cal H such that the set {T_1^{k_1} T_2^{k_2}... T_n^{k_n}x : k_i \geq 0, i=1,2,...n} is dense in \cal H. In this paper, we give sufficient conditions under which the adjoint of an n-tuple of a weighted composition operator on a Hilbert space of analytic functions is hypercyclic.
Generalized Berwald Metrics, Esmaeil Peyghan, Akbar Tayebi
Generalized Berwald Metrics, Esmaeil Peyghan, Akbar Tayebi
Turkish Journal of Mathematics
In this paper, we consider a class of Finsler metrics called generalized Berwald metrics which contains the class of Berwald metrics as a special case. We prove that every generalized Berwald metrics with non-zero scalar flag curvature or isotropic Berwald curvature is a Randers metric. Then we prove that on generalized Berwald metrics, the notions of generalized Landsberg and Landsberg curvatures are equivalent.
Bruhat-Chevalley Order On The Rook Monoid, Mahi̇r Bi̇len Can, Lex E. Renner
Bruhat-Chevalley Order On The Rook Monoid, Mahi̇r Bi̇len Can, Lex E. Renner
Turkish Journal of Mathematics
The rook monoid R_n is the finite monoid whose elements are the 0-1 matrices with at most one nonzero entry in each row and column. The group of invertible elements of R_n is isomorphic to the symmetric group S_n. The natural extension to R_n of the Bruhat-Chevalley ordering on the symmetric group is defined in [1]. In this paper, we find an efficient, combinatorial description of the Bruhat-Chevalley ordering on R_n. We also give a useful, combinatorial formula for the length function on R_n.
Lower Bounds For The Maximum Genus Of 4-Regular Graphs, Ding Zhou, Rongxia Hao, Weili He
Lower Bounds For The Maximum Genus Of 4-Regular Graphs, Ding Zhou, Rongxia Hao, Weili He
Turkish Journal of Mathematics
This paper investigates the maximum genus and upper embeddability of connected 4-regular graphs. We obtain lower bounds on the maximum genus of connected 4-regular simple graphs and connected 4-regular graphs without loops in terms of the Betti number. The definition of the Betti number is referred to [Gross and Tucker, Topological Graph Theory, New York, 1987]. Furthermore, we give examples that show that these lower bounds are tight.
Multiplication Modules With Krull Dimension, Mahmood Behboodi, Maryam Molakarimi
Multiplication Modules With Krull Dimension, Mahmood Behboodi, Maryam Molakarimi
Turkish Journal of Mathematics
In ring theory, it is shown that a commutative ring R with Krull dimension has classical Krull dimension and satisfies k.dim(R)=cl.k.dim(R). Moreover, R has only a finite number of distinct minimal prime ideals and some finite product of the minimal primes is zero (see Gordon and Robson [9, Theorem 8.12, Corollary 8.14, and Proposition 7.3]). In this paper, we give a generalization of these facts for multiplication modules over commutative rings. Actually, among other results, we prove that if M is a multiplication R-module with Krull dimension, then: (i) M is finitely generated, (ii) R has finitely many minimal prime …
Essential Normality For Certain Weighted Composition Operators On The Hardy Space H^2, Mahsa Fatehi, Bahram Khani Robati
Essential Normality For Certain Weighted Composition Operators On The Hardy Space H^2, Mahsa Fatehi, Bahram Khani Robati
Turkish Journal of Mathematics
We characterize the essentially normal weighted composition operators C_{\psi,\varphi} on the Hardy space H^2, whenever \varphi is a linear-fractional transformation and \psi \in A(D). Also we investigate the essential normality problem for some other weighted composition operators on H^2.
On Similarity Of Powers Of Shift Operators, Masoumeh Faghih Ahmadi, Karim Hedayatian
On Similarity Of Powers Of Shift Operators, Masoumeh Faghih Ahmadi, Karim Hedayatian
Turkish Journal of Mathematics
Let M_z and B denote, respectively, the multiplication operator and the backward shift operator on a weighted Hardy space. We present sufficient conditions so that M_{z^n} is similar to \bigoplus_1^nM_z, and B^n is similar to \bigoplus_1^nB. The first part generalizes a result obtained by Yucheng Li.
An Identity Between The M-Spotty Weight Enumerators Of A Linear Code And Its Dual, İrfan Şi̇ap
An Identity Between The M-Spotty Weight Enumerators Of A Linear Code And Its Dual, İrfan Şi̇ap
Turkish Journal of Mathematics
The m-spotty byte error control codes provide a good source for detecting and correcting errors in semiconductor memory systems using high density RAM chips with wide I/O data (e.g. 8, 16, or 32 bits). m-spotty byte error control codes are very suitable for burst correction. Here, we introduce the m-spotty weights and m-spotty weight enumerator of linear codes over the ring F_2+uF_2 and prove a MacWilliams type identity.
Four-Component Synthesis Of 1,3,4-Oxadiazole Derivatives From N-Isocyaniminotriphenylphosphorane, Aromatic Carboxylic Acids, Aromatic Bis-Aldehydes, And Secondary Amines, Ali Ramazani, Zahra Karimi, Ali Souldozi, Yavar Ahmadi
Four-Component Synthesis Of 1,3,4-Oxadiazole Derivatives From N-Isocyaniminotriphenylphosphorane, Aromatic Carboxylic Acids, Aromatic Bis-Aldehydes, And Secondary Amines, Ali Ramazani, Zahra Karimi, Ali Souldozi, Yavar Ahmadi
Turkish Journal of Chemistry
The 1:1 iminium intermediate generated by the addition of a secondary amine to aromatic bis-aldehydes (isophthalaldehyde and terphthalaldehyde) is trapped by the N-isocyaniminotriphenylphosphorane in the presence of a aromatic carboxylic acid derivative, which leads to the formation of corresponding iminophosphorane intermediate. Then disubstituted 1,3,4-oxadiazole derivatives are formed via intramolecular aza-Wittig reaction of the iminophosphorane intermediates. The reactions were completed in neutral conditions at room temperature and the corresponding disubstituted 1,3,4-oxadiazole derivatives were produced in excellent yields.
Synthesis Of \Alpha-Aminonitriles Catalyzed By Montmorillonite K10 In The Presence Of Dicationic Phosphonium Salt In Water Under Ultrasonic Effect, Çi̇ğdem Yildirim, Çi̇ğdem Yolaçan, Feray Aydoğan
Synthesis Of \Alpha-Aminonitriles Catalyzed By Montmorillonite K10 In The Presence Of Dicationic Phosphonium Salt In Water Under Ultrasonic Effect, Çi̇ğdem Yildirim, Çi̇ğdem Yolaçan, Feray Aydoğan
Turkish Journal of Chemistry
The synthesis of \alpha-aminonitriles was successfully accomplished by the 1-pot 3-component reaction of several aldehydes with (S)-\alpha-phenylethylamine and sodium cyanide in water in the presence of montmorillonite K10 and dicationic phosphonium salt under ultrasonic effect with good yields and moderate diastereoselectivities.
Comparative Photodecolorization Of Red Dye By Anatase, Rutile (Tio_2), And Wurtzite (Zno) Using Response Surface Methodology, Shahab Khameneh Asl, Sayad Khatib Sadrnezaad, Mansour Keyanpour-Rad, Deni̇z Üner
Comparative Photodecolorization Of Red Dye By Anatase, Rutile (Tio_2), And Wurtzite (Zno) Using Response Surface Methodology, Shahab Khameneh Asl, Sayad Khatib Sadrnezaad, Mansour Keyanpour-Rad, Deni̇z Üner
Turkish Journal of Chemistry
Treatment of dye pollution containing C.I. Acid Red 14 (AR14) by a coupled photocatalytic process was studied. Titanium dioxide, in the form of anatase and rutile, and zinc oxide, were used as photocatalysts. The investigated photocatalysts were Aldrich-produced nanopowders with crystallites of a mean size of 20-30 nm and a specific surface area of about 50 m^2/g. A comparison of TiO_{2(anatase)}, TiO_{2(rutile)}, TiO_{2(a,r)}, and ZnO for the decolorization of the AR14 solution was performed. Results showed that color removal followed the decreasing order of TiO_{2(a,r)}, ZnO > TiO_{2(a,r)} > TiO_{2(a)}, ZnO > TiO_{2(r)}, ZnO >TiO_{2(a,r)} > TiO_{2(a)} > ZnO > TiO_{2(r)}. Response surface methodology (RSM) was …
A Dft Study On The Structural And Optical Properties And Cation Selectivities Of Some Metal-Coumarin-Crown Ether Complexes, Emi̇ne Esra Kasapbaşi, Mi̇ne Yurtsever
A Dft Study On The Structural And Optical Properties And Cation Selectivities Of Some Metal-Coumarin-Crown Ether Complexes, Emi̇ne Esra Kasapbaşi, Mi̇ne Yurtsever
Turkish Journal of Chemistry
Macrocyclic ethers are well-known molecules because of their high cation-binding capacities. They form stable complexes with alkaline and soil alkaline metals through strong oxygen bridges in solution. For enhanced optical properties, a new series of crown ethers was synthesized with a coumarin ring fused to it. The effects of the position of the coumarin ring, the type of the substituent on the coumarin ring, and the size of the crown on the optical properties of the material were studied according to the density functional theory (DFT) method at the B3LYP/6-31g(d) level of theory in the gas phase as well as …
Surfactant-Sensitized Spectrophotometric Determination Of Hg(Ii) In Water Samples Using 2-(2-Thiazolylazo)- P-Cresol As Ligand And Cetylpyridinium Chloride As Cationic Surfactant, Ramazan Gürkan, Tuğba Çepken, Hali̇l İbrahi̇m Ulusoy
Surfactant-Sensitized Spectrophotometric Determination Of Hg(Ii) In Water Samples Using 2-(2-Thiazolylazo)- P-Cresol As Ligand And Cetylpyridinium Chloride As Cationic Surfactant, Ramazan Gürkan, Tuğba Çepken, Hali̇l İbrahi̇m Ulusoy
Turkish Journal of Chemistry
A new, reliable, surfactant-sensitized method is described for the spectrophotometric determination of total and dissolved inorganic mercury at trace levels. The method is based on the ternary complex formation of Hg(II) with 2-(2-thiazolylazo)-p-cresol and a cationic surfactant, cetylpyridinium chloride, at pH 9.5. The detection and quantification limits of the method with surfactant were 6 and 19 \mu g L^{-1}, while those of the method without surfactant were 22 and 67 \mu g L^{-1}, respectively. The method obeys Beer's law at up to approximately 10 mg L^{-1} Hg(II) in an aqueous surfactant medium. The relative errors and relative standard deviations of …
Synthesis, Characterization, And Microwave-Promoted Catalytic Activity Of Novel Benzimidazole Salts Bearing Silicon-Containing Substituents In Heck-Mizoroki And Suzuki-Miyaura Cross-Coupling Reactions Under Aerobic Conditions, Hasan Küçükbay, Ni̇hat Şi̇reci̇, Ülkü Yilmaz, Selma Deni̇z, Mehmet Akkurt, Zeli̇ha Baktir, Orhan Büyükgüngör
Synthesis, Characterization, And Microwave-Promoted Catalytic Activity Of Novel Benzimidazole Salts Bearing Silicon-Containing Substituents In Heck-Mizoroki And Suzuki-Miyaura Cross-Coupling Reactions Under Aerobic Conditions, Hasan Küçükbay, Ni̇hat Şi̇reci̇, Ülkü Yilmaz, Selma Deni̇z, Mehmet Akkurt, Zeli̇ha Baktir, Orhan Büyükgüngör
Turkish Journal of Chemistry
A number of benzimidazole derivatives (1-8) were synthesized and the catalytic activity of these compounds in a catalytic system including Pd(OAc)_2 and K_2CO_3 in DMF-H_2O was evaluated in Heck-Mizoroki and Suzuki-Miyaura cross-coupling reactions of aryl iodides, bromides, and chlorides with styrene and arylboronic acids under microwave irradiation and aerobic conditions. The yields of both the Heck-Mizoroki and the Suzuki-Miyaura cross coupling reactions with aryl iodides and aryl bromides were nearly quantitative. The synthesized 1-substituted benzimidazole (1) and benzimidazole salts (2-8) were identified by ^1H- and ^{13}C-NMR and IR spectroscopic methods, and micro analysis. The molecular structure of 7 was also …
Preparation And Antimicrobial Activity Evaluation Of Some Quinoline Derivatives Containing An Azole Nucleus, Muhammet Özyanik, Serpi̇l Demi̇rci̇, Hakan Bektaş, Nesli̇han Demi̇rbaş, Ahmet Demi̇rbaş, Şengül Alpay Karaoğlu
Preparation And Antimicrobial Activity Evaluation Of Some Quinoline Derivatives Containing An Azole Nucleus, Muhammet Özyanik, Serpi̇l Demi̇rci̇, Hakan Bektaş, Nesli̇han Demi̇rbaş, Ahmet Demi̇rbaş, Şengül Alpay Karaoğlu
Turkish Journal of Chemistry
Quinoline-2-carbohydrazide (2) obtained from quinaldic acid (1) was converted to the corresponding carbothioamide 3 and carboxamide 6 by treatment with benzyliso(thio)cyanate. The basic treatment of 3 and 6 yielded the corresponding 1,2,4-triazole derivatives 4 and 7. The synthesis of 5-(quinolin-2-yl)-1,3,4- oxadiazol-2-thiol (9) was performed from the reaction of 1 with CS_2 in basic media. The Mannich reaction of compounds 4, 7, and 9 resulted in the formation of aminoalkylated derivatives 5a-c, 8, and 10a,b. The condensation of 1 with thiosemicarbazide, carbohydrazide, or thiocarbohydrazide gave the corresponding 1,2,4-triazole derivatives (11-13). The treatment of 4-amino-5-(quinolin-2-yl)- 4H-1,2,4-triazole-3-thiol (13) with 4-chlorophenacyl bromide caused the …
Synthesis And Evaluation Of Enzyme Inhibitory Potential Of Some Derivatives Of Scopolamine, Durre Shahwar, Muhammad Asam Raza, Tania Khan
Synthesis And Evaluation Of Enzyme Inhibitory Potential Of Some Derivatives Of Scopolamine, Durre Shahwar, Muhammad Asam Raza, Tania Khan
Turkish Journal of Chemistry
This study was designed to synthesize and evaluate derivatives of scopolamine (1) as acetylcholine esterase and protease inhibitors. Scopolamine (1) was extracted from the aerial parts of Datura innoxia through bioassay guided fractionation. Five different derivatives of scopolamine (1) were synthesized, and identified through spectroscopic studies. Their acetylcholine esterase (AChE) and trypsin inhibitory potentials were determined through standard protocols and evaluated from the perspective of structure-activity relationship. The synthesized scopolamine derivatives (2-6) showed remarkable AChE inhibitory activity, except for scopoline (6). The results showed higher enzyme inhibition potential of the synthesized compounds (2-5) as compared to scopolamine (1). Maximum inhibition …
Copolymerization Of N-Vinyl Pyrrolidone With Methyl Methacrylate By Ti(Iii)-Dmg Redox Initiator, Ajithkumar Manayan Parambil, Yashoda Malagar Puttaiahgowda, Prasannakumar Shankarappa
Copolymerization Of N-Vinyl Pyrrolidone With Methyl Methacrylate By Ti(Iii)-Dmg Redox Initiator, Ajithkumar Manayan Parambil, Yashoda Malagar Puttaiahgowda, Prasannakumar Shankarappa
Turkish Journal of Chemistry
Redox copolymerization of N-vinyl-2-pyrrolidone (NVP) with methyl methacrylate (MMA) was carried out using titanium(III)-- dimethylglyoxime [Ti(III)-DMG] redox initiator in aqueous sulfuric acid-alcohol media. The resulting copolymer was characterized by FTIR, ^1H-NMR, and ^{13}C-NMR spectroscopic methods and elemental analysis. Thermal properties of the copolymer were determined by differential scanning calorimetric technique and thermogravimetric analysis. The reactivity ratios of the monomers were computed by Fineman-Ross, Kelen-Tudos, and extended Kelen-Tudos methods at lower conversion. The reactivity ratios obtained r_1 (MMA) 1.69 and r_2 (NVP) 0.03 showed richer content of MMA than NVP in the copolymer having extreme ideal behavior. The distribution of monomer …
Design And Synthesis Of New 1,2,4-Triazole Derivatives Containing Morpholine Moiety As Antimicrobial Agents, Deni̇z Şahi̇n, Hacer Bayrak, Ahmet Demi̇rbaş, Nesli̇han Demi̇rbaş, Şengül Alpay Karaoğlu
Design And Synthesis Of New 1,2,4-Triazole Derivatives Containing Morpholine Moiety As Antimicrobial Agents, Deni̇z Şahi̇n, Hacer Bayrak, Ahmet Demi̇rbaş, Nesli̇han Demi̇rbaş, Şengül Alpay Karaoğlu
Turkish Journal of Chemistry
2-Morpholine-4ylethyl-3H-1,2,4-triazole-3-ones (2a, 2b) were obtained from the condensation between the corresponding ethoxycarbonylhydrazones and 2-morpholinoethanamine. 2a was converted to acetohydrazide (4) via the formation of an ester derivative (3). Treatment of 2a and 2b with several aryl sulfonyl chlorides afforded the corresponding 2-arylsulfonyl-1,2,4-triazole-3-ones (5a-c and 6). The reaction of hydrazide (4) with benzyl iso- and benzyl isothiocyanate produced the corresponding carboxamide (8a) and carbothioamide (8b). The basic treatment of 8b yielded 5-mercapto-4H-1,2,4-triazol-3-yl)methyl]-2,4-dihydro-3H-1,2,4-triazol-3-one (10). The synthesis of 1,3-thiazol-2(3H)-ylidene-1,2,4-triazol-1- ylacetohydrazide (11) and 1,3-oxazole-2(3H)-ylidene-1,2,4-triazole- 1-yl)acetohydrazide (9) derivatives was performed from the reaction of 8a and 8b with substituted phenacyl bromides. All the newly synthesized …
Titrimetric Determination Of Anionic Surfactant Content In Anionic/Nonionic Surfactant Mixture Solution By Anionic Surfactant Selective Electrode, Junwei Wang, Zhiping Du, Wanxu Wang, Wei Xue
Titrimetric Determination Of Anionic Surfactant Content In Anionic/Nonionic Surfactant Mixture Solution By Anionic Surfactant Selective Electrode, Junwei Wang, Zhiping Du, Wanxu Wang, Wei Xue
Turkish Journal of Chemistry
A new polyvinyl chloride (PVC) membrane electrode for determining the concentration of sodium dodecylsulfate (SDS) based on a neutral ion pair complex of dodecyltrimethylammonium-dodecylsulfate (DTA^+DS^-) as ionophore is described in this paper. The construction and characteristic performance of the PVC membrane electrode displays a Nernstian slope of --56.9 \pm 0.3 mV/decade in the concentration range of 2.0 \times 10^{-6} to 3.2 \times 10^{-3} mol L^{-1} and a detection limit of 1.6 \times 10^{-6} mol L^{-1}. The lifetime of the electrode is more than 3 months without showing significant change in the values of slope or linear concentration range. The electrode …
Facile And Rapid Synthesis Of Some Novel Polysubstituted Imidazoles By Employing Magnetic Fe_3o_4 Nanoparticles As A High Efficient Catalyst, Bahador Karami, Khalil Eskandari, Abdolmohammad Ghasemi
Facile And Rapid Synthesis Of Some Novel Polysubstituted Imidazoles By Employing Magnetic Fe_3o_4 Nanoparticles As A High Efficient Catalyst, Bahador Karami, Khalil Eskandari, Abdolmohammad Ghasemi
Turkish Journal of Chemistry
Multicomponent, one-pot, highly efficient, and environmentally adapted synthesis of some novel polysubstituted imidazoles by the use of various aldehydes, benzil, aliphatic, and aromatic primary amines and ammonium acetate in the presence of Fe_3O_4 nanoparticles as catalyst under solvent-free condition is explained. A highly efficient role of Fe_3O_4 nanoparticles as catalyst in this synthesis was shown. By this advantage, several polysubstituted imidazoles as pharmaceutical important molecules can be prepared in high yield and high purity. This method is very easy and rapid for the synthesis of imidazole derivatives. All products were deduced from their IR and NMR spectroscopic data. The Fe_3O_4 …
Determination Of Ultratrace Amounts Of Dichloro-Nitrobenzene And Dichloro-Nitroaniline In Water Samples Using Solidified Floating Organic Drop Microextraction (Sfodme) And Gas Chromatography, Shayessteh Dadfarnia, Mohammad Mirzaei, Ali Mohammad Haji Shabani, Batoul Ramazanzadeh
Determination Of Ultratrace Amounts Of Dichloro-Nitrobenzene And Dichloro-Nitroaniline In Water Samples Using Solidified Floating Organic Drop Microextraction (Sfodme) And Gas Chromatography, Shayessteh Dadfarnia, Mohammad Mirzaei, Ali Mohammad Haji Shabani, Batoul Ramazanzadeh
Turkish Journal of Chemistry
Solidified floating organic drop microextraction (SFODME) in combination with gas chromatography with an electron capture detector was used for separation/enrichment and determination of 2,5-dichloro-nitrobenzene, 2,3-dichloro-nitrobenzene, and 2,6-dichloro-4-nitroaniline in water samples. The main parameters affecting the performance of SFOME, such as solvent volume, extraction time, stirring rate, extraction temperature, sample volume, nature of the solvent and ionic strength were optimized. Under the optimum experimental conditions, good relative standard deviations of 7.5%, 6.9%, and 9.3% for 7 extractions and determination of 50 ng L^{-1} of 2,5-dichloro-nitrobenzene, 2,3-dichloro-nitrobenzene and 2,6-dichloro-4-nitroaniline were obtained, respectively. Enrichment factors of 1390, 1398, and 1362 and detection limits …
Synthesis And Application Of L-Proline And R-Phenylglycine Derived Organocatalysts For Direct Asymmetric Michael Addition Of Cyclohexanone To Nitroalkenes, Hayri̇ye Nevi̇n Naziroğlu, Abdulkadi̇r Sirit
Synthesis And Application Of L-Proline And R-Phenylglycine Derived Organocatalysts For Direct Asymmetric Michael Addition Of Cyclohexanone To Nitroalkenes, Hayri̇ye Nevi̇n Naziroğlu, Abdulkadi̇r Sirit
Turkish Journal of Chemistry
Novel R-phenylglycine derived organocatalysts were prepared from the reaction of Cbz-R-phenylglycine with indoline, pyrrolidine, or (S)-(-)-2-(diphenylmethyl)pyrrolidine in 3 steps. The asymmetric Michael addition of cyclohexanone to nitroolefins was investigated using R-phenylglycine derivatives along with L-prolinamides as chiral catalysts. The desired products were obtained in excellent yields with enantioselectivities up to 90% ee and diastereomeric ratio up to 98:2 of the syn }addition product.
A One-Pot Efficient Four-Component Reaction For The Synthesis Of 2-(Arylamino)-2-(5-Aryl-1-Ethenyl-1,3,4-Oxadiazol-2-Yl)Propyl Benzoate (Or 4-Bromobenzoate) Derivatives, Mohsen Valizadeh Holagh, Abel Mohammadali Oglu Maharramov, Mirza Aliakbar Oglu Allahverdiyev, Ali Ramazani, Yavar Ahmadi, Fatemeh Zeinali Nasrabadi, Ali Souldozi
A One-Pot Efficient Four-Component Reaction For The Synthesis Of 2-(Arylamino)-2-(5-Aryl-1-Ethenyl-1,3,4-Oxadiazol-2-Yl)Propyl Benzoate (Or 4-Bromobenzoate) Derivatives, Mohsen Valizadeh Holagh, Abel Mohammadali Oglu Maharramov, Mirza Aliakbar Oglu Allahverdiyev, Ali Ramazani, Yavar Ahmadi, Fatemeh Zeinali Nasrabadi, Ali Souldozi
Turkish Journal of Chemistry
Reactions of N-isocyaniminotriphenylphosphorane with 2-oxopropyl benzoate (or 2-oxopropyl 4-bromobenzoate) in the presence of 3-phenyl-2-propynoic acid and primary amines proceeded smoothly at room temperature and in neutral conditions to afford sterically congested 1,3,4-oxadiazole derivatives in high yields. The reaction proceeded smoothly and cleanly under mild conditions and no side reactions were observed.
Synthesis And Characterization Of Bis(Azine) Ligands And Metal Complexes: Dna-Interaction And Extraction Properties For Metals And Dichromate Anions, Sultan Kulaksizoğlu, Cansu Gökçe, Ramazan Güp
Synthesis And Characterization Of Bis(Azine) Ligands And Metal Complexes: Dna-Interaction And Extraction Properties For Metals And Dichromate Anions, Sultan Kulaksizoğlu, Cansu Gökçe, Ramazan Güp
Turkish Journal of Chemistry
Two new bis(bidentate) azine ligands were prepared by linking (1Z,1'Z)-1,1'-{butane-1,4-diylbis[oxyben-zene-4,1- diyl(1Z)eth-1-yl-1-ylidene]}dihydrazine to salicylaldehyde and pyridine-2-carbaldehyde, 1,4-bis{4-{(1E)-1-((2E)-(2- hydroxybenzene--2-ylmethy-lidene)hydrazonylidene)ethyl}phenoxy}butane (H_2L^1), and 1,4-bis{4-{(1E)-1-((2E)-(pyridine--2-ylmethylidene) hydrazonylidene)ethyl}phenoxy}butane (L^2), respecti- vely. Two kinds of copper(II) and nickel(II) complexes with different ligands were prepared. Reaction of H_2L^1 with Cu(II) and Ni(II) acetate with 1:1 molar ratio gave double stranded binuclear bis(azine) complexes with stoichiometry [M(L^1)]_2 containing {M^{II}N_2O_2} centers. On the other hand, 1:1 molar ratio reaction of Cu(II) and Ni(II) chloride with L^2 yielded mononuclear metal complexes with general stoichiometry [M(L^2)Cl_2] containing {M^{II}N_2N_2} centers. The structures of both bis(azine) ligands and complexes were identified by elemental analysis, infrared …
Chemical And Biotransformation Of Gelomulide F: A Rare Diterpene Lactone, Humaira Yasmeen Gondal, Muhammad Iqbal Choudhary
Chemical And Biotransformation Of Gelomulide F: A Rare Diterpene Lactone, Humaira Yasmeen Gondal, Muhammad Iqbal Choudhary
Turkish Journal of Chemistry
Chemical and biotransformations of a rare diterpene lactone, Gelomulide F (1), from the cytotoxic extract of leaves of Suregada multiflora were studied. Fermentation of compound 1 with Sachromyces cerevisiae transformed it to Gelomulide D (2) and E (3), whereas its treatment with 2N KOH yielded Gelomulide D (2). In addition, a novel compound (4) was obtained by its diastereo and chemoselective reduction with NaBH_4. All of these compounds were characterized on the basis of extensive ^1H-NMR, ^{13}C-NMR, 2D NMR, and mass spectral analyses.