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Neolignan And Phenylethanoid Glycosides From Verbascum Salviifolium Boiss, Zeli̇ha Ş. Akdemi̇r, İ. İrem Tatli, Erdal Bedi̇r, Ikhlas A. Khan
Neolignan And Phenylethanoid Glycosides From Verbascum Salviifolium Boiss, Zeli̇ha Ş. Akdemi̇r, İ. İrem Tatli, Erdal Bedi̇r, Ikhlas A. Khan
Turkish Journal of Chemistry
From the aerial parts of Verbascum salviifolium Boiss., 2 neolignan glucosides, dehydrodiconiferyl alcohol-9'-O-\beta -D-glucopyranoside (1) and dehydrodiconiferyl alcohol-9-O-\beta- D-glucopyranoside (2), along with 5 phenylethanoid glycosides, acteoside (= verbascoside) (3), \beta -hydroxyacteoside (4), forsythoside B (5), angoroside A (6) and martynoside (7), were isolated. The structure elucidation of the isolated compounds was established on the basis of spectroscopic evidence. Compounds 1-7 demonstrated scavenging properties toward the 1,1-diphenyl-2-picrylhydrazyl (DPPH) radical in TLC autographic and spectroscopic assays.
Synthesis And Antitumor Activities Of Some New 4-(1-Naphthylidenamino)- And 4-(1-Naphthylmethylamino)-1,2,4-Triazol-5-One Derivatives, Nesli̇han Demi̇rbaş, Reyhan Uğurluoğlu
Synthesis And Antitumor Activities Of Some New 4-(1-Naphthylidenamino)- And 4-(1-Naphthylmethylamino)-1,2,4-Triazol-5-One Derivatives, Nesli̇han Demi̇rbaş, Reyhan Uğurluoğlu
Turkish Journal of Chemistry
A series of 4-(1-naphthylidenamino)-1,2,4-triazol-5-one derivatives (3a-e) were synthesized by condensation of corresponding 3-alkyl-4-amino-4,5-dihydro-1H-1,2,4-triazol-5-ones with 1-naphthaldehyde. Acetylation and alkylation of these compounds gave 4a-e and 5a-e, respectively. Sodium borohydride reduction of 1-naphthylidenamino derivatives afforded naphthylmethylamino derivatives, which were subsequently acetylated. Depending on the duration of the acetylation, mono or bis acetamide derivatives were obtained. The in vitro antitumor activities of some selected compounds were screened and compounds 3e, 5c, 6e and 9c} were found to be active.
Bromination Of Tricyclo[7.2.1.0^{2,7}]Dodeca-2,4,6,10-Tetraene Derivatives: Electronic And Neighboring Group Effects On Bromination, Ari̇f Daştan
Turkish Journal of Chemistry
The bromination reaction of tricyclo[7.2.1.0^{2,7}]dodeca-2,4,6,10-tetraene derivatives was studied. The bromination of 9 gave only rearranged products 12 and 13, while the bromination of 8 with molecular bromine formed both rearranged 12 and non-rearranged products 15 and 16. The possible role of a substituent in the rearrangements was examined. All compounds were characterized properly, in particular by NMR spectra and chemical transformation.
An Atropisomeric Chiral 2,2'-Bipyridyl-3,3'-Dicarboxylic Acid And Corresponding Platinum(Ii) Complex, Abdurrahman Şengül
An Atropisomeric Chiral 2,2'-Bipyridyl-3,3'-Dicarboxylic Acid And Corresponding Platinum(Ii) Complex, Abdurrahman Şengül
Turkish Journal of Chemistry
2,2'-Bipyridyl-3,3'-dicarboxylic acid (H_2BDC) spontaneously resolves on crystallization from water, giving monohydrated crystals of the space group P2_12_12_1. In any individual crystal, all the atropisomeric-skewed molecules are of one hand; however, on dissolution in water, optical activity is lost. Strong hydrogen bonding leads to a helical structure, via O--H ... N links, and 3 further strong bonds between water and carboxylate groups produce a framework structure. The pK_a values measured for H_2BDC (3.18 \pm 0.04 and 4.59 \pm 0.02 at 20 \pm 1 °C, in dilute aqueous solution) agree with the zwitterionic form. The reaction of H_2BDC with potassium tetrachloroplatinate(II) in …
External Mass Transfer Studies During The Adsorptions Of Some Dyestuffs And P-Nitrophenol Onto Chitosan From Aqueous Solution, İlhan Uzun, Fuat Güzel
External Mass Transfer Studies During The Adsorptions Of Some Dyestuffs And P-Nitrophenol Onto Chitosan From Aqueous Solution, İlhan Uzun, Fuat Güzel
Turkish Journal of Chemistry
The effect of temperature on the adsorptions of some dyestuffs [orange II (O-II), crystal violet (CV) and reactive blue 5 (RB5)] and an ideal adsorbate p-nitrophenol (PNP) by chitosan (Sigma C 3646) from aqueous solution was investigated. The experimental data related to adsorption isotherms were applied to linear forms of the equations that they fitted, and isotherm constants were calculated. Since the isotherm curves obtained for the adsorptions of O-II and CV by chitosan fitted the Langmuir adsorption isotherm, the Langmuir constants (q_m and b) related to the adsorption isotherms of these dyestuffs together with their kinetical data at different …
Main Flavonoids Of Tilia Argentea Desf. Ex Dc. Leaves, Gülnur Toker, Merve Memi̇şoğlu, Erdem Yeşi̇lada, Mustafa Aslan
Main Flavonoids Of Tilia Argentea Desf. Ex Dc. Leaves, Gülnur Toker, Merve Memi̇şoğlu, Erdem Yeşi̇lada, Mustafa Aslan
Turkish Journal of Chemistry
No abstract provided.
X-Ray Diffraction Study Of The Changes Induced During The Thermal Degradation Of Poly (Methyl Methacrylate) And Poly (Methacryloyl Chloride), Rizwan Hussain, Din Mohammad
X-Ray Diffraction Study Of The Changes Induced During The Thermal Degradation Of Poly (Methyl Methacrylate) And Poly (Methacryloyl Chloride), Rizwan Hussain, Din Mohammad
Turkish Journal of Chemistry
Poly (methyl methacrylate) -- PMMA -- and poly (methacryloyl chloride) -- PMACl -- were synthesized by free radical solution polymerization. The thermal stabilities of these polymers were determined with the help of thermogravimetry and differential thermal analysis. The structural changes in these materials at different temperatures (90, 140, 220 and 410 °C) were studied by X-ray diffraction. These studies indicate that PMACl is less amorphous than PMMA due to the presence of bulky chloride groups
Synthesis, Spectral And Thermal Properties Of Some Penta-Coordinated Complexes Of Oxovanadium(Iv) Derived From Thiosemicarbazones Of 4-Aminoantipyrine, Ram K. Agarwal, Surendra Prasad, Neetu Gahlot
Synthesis, Spectral And Thermal Properties Of Some Penta-Coordinated Complexes Of Oxovanadium(Iv) Derived From Thiosemicarbazones Of 4-Aminoantipyrine, Ram K. Agarwal, Surendra Prasad, Neetu Gahlot
Turkish Journal of Chemistry
The paper reports the synthesis of crystalline oxovanadium(IV), VO^{2+}, complexes of thiosemicarbazones, i.e. 4[N-(4'-nitrobenzalidene)amino]antipyrine thiosemicarbazone (4'-NO_2BAAPTS) and 4[N-(furan-2'-aldimine)amino]antipyrine thiosemicarbazone (FFAAPTS) with general composition VOX_2L (X = Cl, Br, I, NO_3 or NCS) and VO(ClO_4)_2(L)H_2O (L = 4'-NO_2BAAPTS or FFAAPTS). All the complexes were characterized by elemental analyses, molar mass, molar conductance, magnetic susceptibility, infrared and electronic spectra. In all the complexes, both the thiosemicarbazones behave as neutral tridentate (N, N, S) ligands. The thermal properties of the representative complexes are also reported. The most probable geometry of the complexes is proposed.
Phenylpropanoid Glycosides From Linum Olympicum (Linaceae), Belma Konuklugi̇l, Özlem Bahadir
Phenylpropanoid Glycosides From Linum Olympicum (Linaceae), Belma Konuklugi̇l, Özlem Bahadir
Turkish Journal of Chemistry
The lignan content of Linum olympicum Boiss. was investigated by HPLC and GC-MS in comparison with standards, and 2 phenylpropanoid glycosides, syringin (1) and coniferin (2), were isolated from the aerial parts. Identification of the 2 compounds was achieved by comparison with standards using TLC and HPLC and the structures of the isolated compounds were established by UV and ^1H-NMR analysis.
Methoxyflavonoids From Pinaropappus Roseus, Ü. Şebnem Harput, İclal Saracoğlu, Yukio Ogihara
Methoxyflavonoids From Pinaropappus Roseus, Ü. Şebnem Harput, İclal Saracoğlu, Yukio Ogihara
Turkish Journal of Chemistry
Three rare methoxyflavonoids, rhamnazin 3-O-rutinoside (1), rhamnocitrin 3-O-rutinoside (2) and isorhamnetin 3-O-rutinoside (3), were isolated from the methanolic extract of Pinaropappus roseus together with 2 well-known flavonoids, quercetin 3-O-rutinoside (=rutin) (4) and kaempferol 3-O-rutinoside (5). The structures of the isolated compounds were elucidated on the basis of UV, 1D and 2D NMR and FAB-Mass spectral analysis. Free radical scavenging activities of the isolated compounds were also demonstrated. This is the first report on the chemical composition of the genus Pinaropappus.
The Crystal And Molecular Structure Of 1-(2-Chloro-Benzoyl)-3-P-Tolyl-Thiourea, Hakan Arslan, Ulrich Flörke, Nevzat Külcü
The Crystal And Molecular Structure Of 1-(2-Chloro-Benzoyl)-3-P-Tolyl-Thiourea, Hakan Arslan, Ulrich Flörke, Nevzat Külcü
Turkish Journal of Chemistry
1-(2-Chloro-benzoyl)-3-p-tolyl-thiourea was synthesized and characterized by elemental analysis and IR spectroscopy. The crystal and molecular structure of the title compound was determined from single-crystal X-ray diffraction data. It crystalizes in the triclinic space group P-1, with a = 7.9942(9) Å, b = 9.531(1) Å, c = 11.075(1) Å, \alpha = 97.235(2) °, \beta = 111.099(2) °, and \gamma = 106.105(2) °.
Acylated Flavone Glycosides From Veronica Pectinata Var. Glandulosa And V. Persica, İclal Saracoğlu, Ü. Şebnem Harput, Yukio Ogihara
Acylated Flavone Glycosides From Veronica Pectinata Var. Glandulosa And V. Persica, İclal Saracoğlu, Ü. Şebnem Harput, Yukio Ogihara
Turkish Journal of Chemistry
This study deals with the isolation of a new acylated 5,6,7,3',4'-pentahydroxy-flavone glycoside (1) and 3 known allose-containing acylated flavone glycosides (2-4) as well as a known flavone aglycone (5) from the aerial parts of Veronica pectinata var. glandulosa and V. persica. The structures of the isolated compounds were determined to be 3' -hydroxy-4'-O-methylscutellarein-7-O-[2''-O-\alpha -L-rhamnopyranosyl-3''-O-(6''''-O-acetyl-\beta -D-glucopyranosyl)]-\beta- D-glucopyranoside, named sarachoside (1), 4' -O-methylisoscutellarein-7-O-2''- O-(6''' -O-acetyl-\beta -D-allopyranosyl)-\beta -D-glucopyranoside (2), isos\-cutellarein-7-O-2''-O-(6'''-O-acetyl-\beta-D-allopyranosyl)-\beta- D-glucopyranoside (3), 3'-hydroxy-4'-O-methy\-lisoscutellarein-7-O-2'' -O-(6'''-O-acetyl-\beta -D-allopyranosyl)-\beta -D-glucopyranoside (4) and 5,4'-dihydroxy-6,7,3' -trimethoxyflavone, named circilineol (5) by extensive 1-D and 2D-NMR spectroscopy. Sarachoside (1) exhibited potent radical scavenging activity against 2,2-diphenyl-1-picrylhydrazyl (DPPH) radical.
Secondary Metabolites From Phlomis Kotschyana, Ü. Şebnem Harput, İclal Saracoğlu, İhsan Çaliş, Ali̇ Arslan Dönmez, Akito Nagatsu
Secondary Metabolites From Phlomis Kotschyana, Ü. Şebnem Harput, İclal Saracoğlu, İhsan Çaliş, Ali̇ Arslan Dönmez, Akito Nagatsu
Turkish Journal of Chemistry
A lignan glycoside, syringaresinol-4',4''-O-di-\beta -D-glucopyranoside (1) (=liriodendrin), 4 phenylethanoid glycosides, acteoside (2), isoacteoside (3), forsythoside B (4) and leucosceptoside B (5), a caffeic acid ester, chlorogenic acid (6) and 2 iridoid glucosides, lamiide (7) and auroside (8), were isolated from the methanolic extracts of the aerial parts of Phlomis kotschyana along with an acetophenone glycoside, 4-hydroxyacetophenone 4-O-[6'-O-\beta -D-apiofuranosyl]-\beta -D-glucopyranoside (9). The structures of the isolated compounds were identified on the basis of spectroscopic (UV, IR, 1D- and 2D-NMR, and FAB-MS) methods.
Iridoid And Phenylethanoid Glycosides From Verbascum Lasianthum, Zeli̇ha Ş. Akdemi̇r, İ. İrem Tatli, Erdal Bedi̇r, Ikhlas A. Khan
Iridoid And Phenylethanoid Glycosides From Verbascum Lasianthum, Zeli̇ha Ş. Akdemi̇r, İ. İrem Tatli, Erdal Bedi̇r, Ikhlas A. Khan
Turkish Journal of Chemistry
Three iridoid glucosides, 8-O-acethylharpagide (1), harpagoside (2), and 6-O-vanilloylajugol (3), were isolated from the roots of Verbascum lasianthum Boiss. ex Bentham. In addition, 2 phenylethanoid glycosides, verbascoside {=acteoside, [\beta -(3,4-dihydroxyphenyl)-ethyl]-(3' -O-\alpha -L-rhamnopyranosyl)-(4' -O-caffeoyl)-\beta -D-glucopyranoside} (4) and poliumoside {= [\beta -(3,4-dihydroxyphenyl)-ethyl]-(3',6' -O-\alpha -L-dirhamnopyranosyl)-(4' -O-caffeoyl)-\beta -D-glucopyranoside} (5), were also isolated. The structures of all compounds were established by spectroscopic evidence (UV, IR, 1D and 2D NMR, LC-ESIMS). Compounds 2-5 demonstrated scavenging properties toward the 2,2-diphenyl-1-picrylhydrazyl (DPPH) radical in TLC autographic assays.
Effect Of Radiation On The Persistent Length Of A Chain, B. L. Oksengendler, Ni̇gora Turaeva, I. N. Ruban, S. Sh. Rashidova
Effect Of Radiation On The Persistent Length Of A Chain, B. L. Oksengendler, Ni̇gora Turaeva, I. N. Ruban, S. Sh. Rashidova
Turkish Journal of Chemistry
The effect of radiation on the persistent length of a chain in a water solution of polymer is considered in the work. This effect is suggested to be related to the breaking of the hydrogen bonds in hydrate layers around the chain. The kinetic equation of the breakage of the hydrogen bonds is defined and the stationary solution is found with the help of the equation. The expression of average value of the persistent length of the chain at a fixed average number of broken bonds is determined by means of the Poisson distribution. We found that the persistent length …
New Adsorbents From Ti(Opr^{N})_{4} By The Sol-Gel Process: Synthesis, Characterization And Application For Removing Some Heavy Metal Ions From Aqueous Solution, Funda Sayilkan, Hi̇kmet Sayilkan, Sema Erdemoğlu, Şadi̇ye Şener, Murat Akarsu
New Adsorbents From Ti(Opr^{N})_{4} By The Sol-Gel Process: Synthesis, Characterization And Application For Removing Some Heavy Metal Ions From Aqueous Solution, Funda Sayilkan, Hi̇kmet Sayilkan, Sema Erdemoğlu, Şadi̇ye Şener, Murat Akarsu
Turkish Journal of Chemistry
New adsorbents were synthesized by the sol-gel process from the product of a hydrolysis reaction and its coated form of titanium(IV)-n-propoxide for removing some heavy metal ions from aqueous solution. Titanium(IV)-n-propoxide was uncatalyst hydrolyzed with different amounts of water at room temperature and was found to react in a 1:1.6 ratio (mole of Ti:mole of H_{2}O). It was found that the condensation following the hydrolysis reaction was alcohol condensation. The hydrolysis-condensation product was characterized in detail by GC, Karl-Fischer coulometric titrator, NIR-spectroscopy, FT-IR spectroscopy, TG-DTA and elemental analysis. The hydrolysis-condensation product of titanium(IV)-n-propoxide was calcinated at 900 °C after drying …
Synthesis And Characterization Of Cu(Ii) Complexes Of Two Ligands Derived From Malonyl Dichloride, Nevi̇n Karaböcek, Serdar Karaböcek, Hasan Mazlum, İsmai̇l Deği̇rmenci̇oğlu, Keri̇m Serbest
Synthesis And Characterization Of Cu(Ii) Complexes Of Two Ligands Derived From Malonyl Dichloride, Nevi̇n Karaböcek, Serdar Karaböcek, Hasan Mazlum, İsmai̇l Deği̇rmenci̇oğlu, Keri̇m Serbest
Turkish Journal of Chemistry
Two different mononucleating ligands incorporating N_{4} and N_{2}S_{2} donor units, 2-(1,3-benzothiazole-2-yl-methyl)-1,3-benzothiazole (L^{1}) and N,N'-bis-(2-amino-phenyl)-malonamide (H_{2}L^{2}) were synthesized by a new method from malonyl dichloride as starting material, and their mononuclear copper(II) complexes were prepared and characterized by elemental analyses, ^{1}H- and ^{13}C-NMR, IR, magnetic moments and mass spectral studies. Elemental analyses, and stochiometric and spectroscopic data of the metal complexes indicate that the metal ions are coordinated to the nitrogen and sulfur atoms and the data support the proposed structure of L^{1}, H_{2}L^{2} and their mononuclear copper(II) complexes. Moreover, the copper(II) complexes of L^{1} and H_{2}L^{2} have a 1:1 metal …
Anodic Stripping Voltammetric Determination Of Gold On A Polyvinylferrocene Coated Glassy Carbon Electrode, Muammer Kavanoz, Handan Gülce, Atti̇la Yildiz
Anodic Stripping Voltammetric Determination Of Gold On A Polyvinylferrocene Coated Glassy Carbon Electrode, Muammer Kavanoz, Handan Gülce, Atti̇la Yildiz
Turkish Journal of Chemistry
The anodic stripping voltammetric determination of gold was accomplished on a chemically modified glassy carbon electrode in a solution containing chloride ions. A modifying polymer, polyvinylferrocene, was coated by immersing the glassy carbon surface in its solution in methylene chloride followed by solvent evaporation. Tetrahalo complexes of gold, tetrachloroaurate(III) and tetrabromoaurate(III) ions, were found to be reduced to metallic gold by chemical reduction during immersion of the polymer coated electrode into the solution containing aurate(III) ions. This reaction was utilized as means of preconcentration without the need for cathodic electrolysis prior to the anodic stripping of metallic gold. The effects …
A Rapid Spectrophotometric Method To Resolve A Binary Mixture Of Food Colorants (Riboflavine And Sunset Yellow), Mahmure Üstün Özgür
A Rapid Spectrophotometric Method To Resolve A Binary Mixture Of Food Colorants (Riboflavine And Sunset Yellow), Mahmure Üstün Özgür
Turkish Journal of Chemistry
A very simple and rapid spectrophotometric method using measurements at zero-crossing wavelength is described for resolving binary mixtures of riboflavine (E-101) and sunset yellow (E-110) in a powder drink. The assay procedure for E-110 and E-101 involves the extraction of the colorants from the powder drink with pH 4.5 acetate buffer, filtration, appropriate dilution, and measurement of the first derivative absorbance values (denoted as ^1D). Calibration graphs are linear up to 25.0 \mu g.mL^{-1} for E-101 and 40.0 \mu g.mL^{-1} for E-110. The sensitivity and reproducibility of the method were determined by using the synthetic mixtures in different ratios prepared …
Synthesis And Characterization Of Block Copolymers Using Polysiloxane Based Macroazoinitiator, Sennur Deni̇z, Ni̇l Baran, Mesut Akgün, Nalan A. Akgün, Sali̇h Di̇nçer
Synthesis And Characterization Of Block Copolymers Using Polysiloxane Based Macroazoinitiator, Sennur Deni̇z, Ni̇l Baran, Mesut Akgün, Nalan A. Akgün, Sali̇h Di̇nçer
Turkish Journal of Chemistry
Poly(dimethylsiloxane-b-styrene) (PDMS-b-PSt) and poly(dimethylsiloxane-b-methyl methacrylate) (PDMS-b-PMMA) block copolymers containing siloxane segments were studied by the radical polymerizations of vinyl monomers such as styrene (St) and methyl methacrylate (MMA) using polydimethylsiloxane based macroazoinitiator (PDM-MAI) in solution. PDM-MAI was synthesized by reacting hydroxy-terminated polydimethylsiloxane (PDMS) and 4,4'-azobis (4-cyanopentanoyl chloride) (ACPC) having a thermodegradable azo-linkage. The polycondensation reaction between PDMS and ACPC (2:1, molar ratio) was carried out at room temperature. The polymerizations of St and MMA initiated by PDM-MAI were investigated using different PDM-MAI concentrations (1, 5, 10, and 15 wt. %) for various reaction times with a methyl ethyl ketone (MEK)/ …
Kinetics Of Aqueous Pyrite Oxidation By Potassium Dichromate - An Experimental Study, Paul Chirita
Kinetics Of Aqueous Pyrite Oxidation By Potassium Dichromate - An Experimental Study, Paul Chirita
Turkish Journal of Chemistry
The kinetics of pyrite oxidation in perchloric acid solutions were investigated at temperatures ranging from 30°C to 40°C, potassium dichromate concentration from 0.001 to 0.05 mol L^{ - 1}, particle size fractions from 50 to 150 \mu m and pH values down to 2.83. The rate of the oxidation reaction is described by the following expression: r = bkS^{0.51}[K_{2}Cr_{2}O_{7}]^{0.64}[H^{+} ]^{0.22} where S is the surface area of reacting solid, r represents the amount of Fe release in solution per unit surface area per unit time, b is a stoichiometric factor, k is the rate constant, and [K_{2}Cr_{2}O_{7}] and [H^{+} ] …
Synthesis, Characterization And Electrical Conductivity Of Poly(P-Phenylene Vinylene), Ali̇ Çirpan, Zuhal Küçükyavuz, Savaş Küçükyavuz
Synthesis, Characterization And Electrical Conductivity Of Poly(P-Phenylene Vinylene), Ali̇ Çirpan, Zuhal Küçükyavuz, Savaş Küçükyavuz
Turkish Journal of Chemistry
Poly(p-phenylene vinylene) (PPV) was prepared electrochemically from p-xylene-bis(diethylsulphonium chloride) in a solvent-electrolyte couple of acetonitrile-tetrabutylammonium tetrafluoroborate (TBAFB). The polymer obtained from the electrode surface was converted to PPV by the thermal elimination of diethyl sulfide, HCl and ethyl sulfide. PPV was also obtained chemically in order to investigate the effect of the synthetic method on the structure and electrical conductivity. The characterization of the polymers was carried out by means of fourier transform infrared spectrometer (FTIR), differential scanning calorimetry (DSC) and thermal gravimetry analysis (TGA) techniques. The doping effect on the conductivity of the PPV was investigated by using different …
Characterization Of Polyphenol Oxidase From Jerusalem Artichoke (Helianthus Tuberosus), Emi̇ne Zi̇yan, Şule Pekyardimci
Characterization Of Polyphenol Oxidase From Jerusalem Artichoke (Helianthus Tuberosus), Emi̇ne Zi̇yan, Şule Pekyardimci
Turkish Journal of Chemistry
Polyphenol oxidases (PPO) in Jerusalem arthichoke (Helianthus tuberosus) skin and flesh were extracted and purified through (NH_{4})_{2}SO_{4} precipitation, dialysis and gel filtration chromatography. The samples obtained from ammonium sulfate precipitation and dialysis were used for the characterization of crude skin and flesh PPO. Optimum pH values were 7.5 for skin PPO and 8.0 for flesh PPO with 50 mM catechol. The optimum temperatures for skin and flesh PPO were 25 °C and 30 °C respectively with catechol. Six inhibitors were tested in the study and the most effective inhibitors were found to be sodium azide and thiourea for both flesh …
Kinetics And Mechanism Of Oxidation Of Some Hydroxy Butyric Acid Salts By Ditelluratocuprate(Iii) In Alkaline Medium, Jin-Huan Shan, Li-Ping Wang, Shi-Gang Shen, Han-Wen Sun
Kinetics And Mechanism Of Oxidation Of Some Hydroxy Butyric Acid Salts By Ditelluratocuprate(Iii) In Alkaline Medium, Jin-Huan Shan, Li-Ping Wang, Shi-Gang Shen, Han-Wen Sun
Turkish Journal of Chemistry
The kinetics of oxidation of 2-hydroxy butyric acid salt (2-HBAS) and 3-hydroxy butyric acid salt (3-HBAS) by ditelluratocuprate(III) (DTC) were studied spectrophotometrically between 298.2 K and 313.2 K in alkaline medium. The reaction rate showed first order dependence in DTC and a fractional order in HBAS. It was found that the pseudo-first order rate constant k_{obs} increased with an increase in the concentration of OH^- and a decrease in the concentration of TeO_{4}^{2-}. The reaction rate changed with the position of the hydroxyl group. There was a negative salt effect. A plausible mechanism involving a pre-equilibrium of adduct formation between …
Iridoid And Phenylpropanoid Glycosides From Phlomis Samia, P. Monocephala And P. Carica, Funda Nuray Yalçin, Tayfun Ersöz, Pinar Akbay, İhsan Çaliş, Ali̇ Arslan Dönmez, Otto Sticher
Iridoid And Phenylpropanoid Glycosides From Phlomis Samia, P. Monocephala And P. Carica, Funda Nuray Yalçin, Tayfun Ersöz, Pinar Akbay, İhsan Çaliş, Ali̇ Arslan Dönmez, Otto Sticher
Turkish Journal of Chemistry
From the aerial parts of Phlomis samia an iridoid glucoside, shanzhiside methylester (1), and three phenylethanoid glycosides, martynoside (2), 4''-O-acetylmartynoside (3) and samioside (4), were isolated. From the overground parts of P. monocephala two iridoid glucosides, lamiide (5) and ipolamiide (6), as well as three phenylethanoid glycosides, verbascoside (= acteoside) (7), forsythoside B (8), alyssonoside (9), and one lignan glucoside, syringaresinol 4'-O-\beta -D-glucopyranoside (10), were isolated. From the aerial parts of P. carica one phenylethanoid glycoside, verbascoside (= acteoside) (7) and three phenylpropanoid monomeric glucosides, syringin (11), dihydrosyringin (12) and coniferin (13), were isolated. The structures of the isolated compounds …
Production Of An E. Coli Toxin Protein; Colicin A In E. Coli Using An Inducible System, İsa Gökçe, Jeremy H. Lakey
Production Of An E. Coli Toxin Protein; Colicin A In E. Coli Using An Inducible System, İsa Gökçe, Jeremy H. Lakey
Turkish Journal of Chemistry
Colicins are bacterial toxins that kill Escherichia coli and related cells; their mode of action is of interest in protein import and toxicology. Colicins translocate across the E. coli outer membrane and periplasm by interacting with several receptors. This translocation process involves interaction of the colicin with the outer membrane porin OmpF and subsequently with the integral membrane protein TolA. The N-terminal domain of colicin N is involved in the import process. Our aim was to produce a large quantity of colicin A for functional and structural studies. It is a prerequisite to have a correctly folded and stable protein …
Crystal Structure Of Cis-Bis(N,N-Dimethyl-N'-Benzoylthioureato)Palladium(Ii), Göktürk Avşar, Hakan Arslan, Hans-Jurgen Haupt, Nevzat Külcü
Crystal Structure Of Cis-Bis(N,N-Dimethyl-N'-Benzoylthioureato)Palladium(Ii), Göktürk Avşar, Hakan Arslan, Hans-Jurgen Haupt, Nevzat Külcü
Turkish Journal of Chemistry
In this study cis-bis(N,N-dimethyl-N'-benzoylthioureato) palladium(II) is synthesised and the crystal structure is determined by X-ray diffraction methods. It crystallises in the space group P2_{1}/c, with a = 11.943(1) Å, b = 11.713(1) Å, c = 15.345(1) Å, \beta = 93.90(1)°, and D_{calc} = 1.616 g cm^{-1} for Z = 4. The Pd(II) atom is in a four-coordinate geometry consisting of two thiocarbonyl S and two carbonyl O atoms from two ligand groups. The Pd-S and Pd-O bond lengths are 2.2313(6) and 2.0211(16) Å, respectively.