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Articles 10741 - 10770 of 11371
Full-Text Articles in Entire DC Network
Short And Effective Synthesis Of A Thiophene Analogue Of (\Pm)-4-Ipomeanol And Its Biological Evaluation, Jurgen Krauss, Doris Unterreitmeier, Franz Bracher
Short And Effective Synthesis Of A Thiophene Analogue Of (\Pm)-4-Ipomeanol And Its Biological Evaluation, Jurgen Krauss, Doris Unterreitmeier, Franz Bracher
Turkish Journal of Chemistry
The thiophene analogue of (\pm)-4-ipomeanol (1) was prepared in 2 steps starting from 3-iodothiophene and pent-4-yn-2-ol. The key steps were a Sonogashira reaction, followed by HgO catalysed hydratisation of the triple bond. The resulting thiophene was tested in the MTT assay for its cytotoxic activity against HL 60 cells.
Synthesis, Characterization, Crystal Structure And Thermal Behavior Of N'-(4-Chlorobenzoyl)-N,N-Di-N-Butylthiourea And Its Nickel Complex, Hakan Arslan, Ulrich Flörke, Nevzat Külcü, Esra Kayhan
Synthesis, Characterization, Crystal Structure And Thermal Behavior Of N'-(4-Chlorobenzoyl)-N,N-Di-N-Butylthiourea And Its Nickel Complex, Hakan Arslan, Ulrich Flörke, Nevzat Külcü, Esra Kayhan
Turkish Journal of Chemistry
We report the synthesis, structural characterization and thermal behavior of N'-(4-chlorobenzoyl)-N,N-di-n-butylthiourea (HL) and its nickel complex (NiL_2). Some physical properties of the prepared compounds were investigated using elemental analyses, IR, ^1H-NMR, and magnetic susceptibility. The molecular structures of HL and NiL_2 were determined by single crystal X-ray diffraction. HL is a monoclinic, space group P2_1/c with a = 10.7457(5) Å, b = 15.5909(8) Å, c = 10.4536(5) Å, \beta = 104.398(1)°, and V = 1696.34(14) Å^3 with Z = 4 for d_{calc} = 1.280 g/cm^3. NiL_2 is a triclinic, space group P-1 with a = 8.561(3) Å, b = 16.643(6) …
The Synthesis Of 4-Phenoxyphenylglyoxime And 4,4'-Oxybis(Phenylglyoxime) And Their Complexes With Cu(Ii), Ni(Ii) And Co(Ii), Ahmet Coşkun
The Synthesis Of 4-Phenoxyphenylglyoxime And 4,4'-Oxybis(Phenylglyoxime) And Their Complexes With Cu(Ii), Ni(Ii) And Co(Ii), Ahmet Coşkun
Turkish Journal of Chemistry
4-Acetyldiphenyl ether and 4,4'-diacetyldiphenyl ether were synthesized from diphenyl ether and acetyl chloride in the presence of AlCl_3 used as catalyst. Subsequently, their keto oxime and glyoxime derivatives were prepared. The metal complexes of the glyoximes such as Cu(II), Ni(II) and Co(II) were also prepared. The structures of these ligands and their complexes were identified by FT-IR, ^1H NMR and ^{13}C NMR spectral data, elemental analysis and magnetic measurements.
Chemical Constituents Of Galium Tortumense, Zühal Güvenalp, Nurcan Kiliç, Cavi̇t Kazaz, Yusuf Kaya, L. Ömür Demi̇rezer
Chemical Constituents Of Galium Tortumense, Zühal Güvenalp, Nurcan Kiliç, Cavi̇t Kazaz, Yusuf Kaya, L. Ömür Demi̇rezer
Turkish Journal of Chemistry
From the aerial parts of Galium tortumense Ehrend & Schönb.-Tem., 8 iridoid glycosides, a flavonol glycoside, a oleanane-type triterpene acid, an ursan-type triterpene acid and a sterol were isolated. The structures of the compounds were elucidated by high field 1D and 2D NMR and EIMS spectroscopies.
Optical Fluoride Sensing With A Bay Region Functionalized Perylenediimide Dye, Funda Yukruk
Optical Fluoride Sensing With A Bay Region Functionalized Perylenediimide Dye, Funda Yukruk
Turkish Journal of Chemistry
A perylenedimiide (PDI) derivative functionalized at the perylene core (bay region) to carry phenyl boronic acid groups was shown to interact with fluoride with changes in the emission and absorption spectrum. These changes are most likely due to fluoride-induced aggregation and/or quenching of the perylenediimide dye. The dye is also selective; among halide ions, fluoride anions generate a significant response. Thus, this class of PDI derivatives is likely to be useful in practical fluoride sensing.
Terpenic And Phenolic Compounds From Sideritis Stricta, F. Pinar Şahi̇n, Nurten Ezer, İhsan Çaliş
Terpenic And Phenolic Compounds From Sideritis Stricta, F. Pinar Şahi̇n, Nurten Ezer, İhsan Çaliş
Turkish Journal of Chemistry
From the overground parts of an endemic Sideritis species, S. stricta, 4 diterpenes, sideridiol (1), isosidol (2), isolinearol (3), and linearol (4); 2 flavonoid glycosides, isoscutellarein 7-O-[6'''-O-acetyl-\beta -D-allopyranosyl-(1 \to 2)]-\beta -D-glucopyranoside (5), and isoscutellarein 7-O-[6'''-O-acetyl-\beta -D-allopyranosyl-(1 \to 2)]-6''-O-acetyl-\beta -D-glucopyranoside (6); a methoxyflavone, xanthomicrol (7); and a phenylethanoid glycoside, verbascoside (=acteoside) (8) were isolated. The structures of the isolated compounds were established based on spectroscopic evidence (UV, IR, 1D- and 2D-NMR, MS).
Iridoids, Flavonoids And Monoterpene Glycosides From Galium Verum Subsp. Verum, L. Ömür Demi̇rezer, Fi̇li̇z Gürbüz, Zühal Güvenalp, Karsten Ströch, Axel Zeeck
Iridoids, Flavonoids And Monoterpene Glycosides From Galium Verum Subsp. Verum, L. Ömür Demi̇rezer, Fi̇li̇z Gürbüz, Zühal Güvenalp, Karsten Ströch, Axel Zeeck
Turkish Journal of Chemistry
From the aerial parts of Galium verum subsp. verum L. were isolated 7 iridoid glycosides, asperuloside (1), asperulosidic acid (2), deacetyl-asperulosidic acid (3), monotropein (4), 6-O-epi-acetylscandoside (5), daphylloside (6) and deacetyl-daphylloside (7); 2 flavonol glycosides, astragalin [= kaempferol 3-O-\beta-glucopyranoside] (8) and rutin [= quercetin 3-O- rutinoside] (9); and 2 monoterpene glycosides, betulalbuside A (10) and (2E)-2,6-dimethyl-2,7-octadien-1,6-diol-6-O-\beta -glucopyranoside (11). The structures of the isolates were established by 1D and 2D NMR spectroscopy in combination with IR, UV and ESI-MS analysis.
Performance Comparison Between Monolithic C18 And Conventional C18 Particle-Packed Columns In The Liquid Chromatographic Determination Of Propranolol Hcl, Sami El Deeb, Hermann Watzig
Performance Comparison Between Monolithic C18 And Conventional C18 Particle-Packed Columns In The Liquid Chromatographic Determination Of Propranolol Hcl, Sami El Deeb, Hermann Watzig
Turkish Journal of Chemistry
Monolithic and conventional particle-packed columns were applied for the determination of propranolol hydrochloride in the presence of its 2 main degradation products, 3-(1-naphthyloxy)-propane-1,2- diol and 4-isopropyl-1,7-bis-(1-naphthyloxy)-4-azaheptane-2,6-diol. The separations were investigated on monolithic columns at flow rates from 1 to 9 mL/min. Fast and efficient separation was obtained by monolithic columns. The analysis time was decreased by about 5-fold on monolithic columns at a flow rate of 4 mL/min, while maintaining sufficient resolution between propranolol and its degradation products. The method was validated using a set of 3 monolithic columns and compared to a conventional (Superspher) C18 column. The precision for …
Synthesis, Crystal Structure And Antifungal/Antibacterial Activity Of Some Novel Highly Functionalized Benzoylaminocarbothioyl Pyrrolidines, H. Ali̇ Döndaş, Yahya Nural, Ni̇zami̇ Duran, Colin Kilner
Synthesis, Crystal Structure And Antifungal/Antibacterial Activity Of Some Novel Highly Functionalized Benzoylaminocarbothioyl Pyrrolidines, H. Ali̇ Döndaş, Yahya Nural, Ni̇zami̇ Duran, Colin Kilner
Turkish Journal of Chemistry
A series of novel highly functionalized benzoylaminocarbothioyl pyrrolidines were prepared from benzoylisothiocyanate and substituted pyrrolidines in excellent yield. The crystal structure of the novel 1-benzoylaminocarbothioyl-5-(naphthyl)- pyrrolidine-2,3,4-tricarboxylicacid trimethyl ester (3a) was determined by X-ray crystal structure analysis. The synthesized compounds were characterized and screened for their in vitro antibacterial and antifungal activities and toxicity. The prepared compounds were tested against the standard strains: Escherichia coli (ATCC 25922), Enterobacter cloacae (ATCC 13047), Enterococcus faecalis (ATCC 29212), Pseudomonas aeruginosa (ATCC 27853), Staphylococcus aureus (ATCC 29213) and Staphylococcus epidermidis (ATCC 12228) and the yeasts Candida albicans (ATCC 90028), Candida krusei (ATCC 6258), Candida parapsilosis …
Superabsorbency, Ph-Sensitivity And Swelling Kinetics Of Partially Hydrolyzed Chitosan-G-Poly(Acrylamide) Hydrogels, Ali Pourjavadi, Gholam Reza Mahdavinia
Superabsorbency, Ph-Sensitivity And Swelling Kinetics Of Partially Hydrolyzed Chitosan-G-Poly(Acrylamide) Hydrogels, Ali Pourjavadi, Gholam Reza Mahdavinia
Turkish Journal of Chemistry
Acrylamide (AAm) monomer was directly grafted onto chitosan using ammonium persulfate (APS) as an initiator and methylenebisacrylamide (MBA) as a crosslinking agent under an inert atmosphere. Two factors affecting the swelling capacity of the obtained hydrogel, AAm and MBA concentrations, were studied. The polymer structures were characterized by FTIR spectroscopy. Water absorbencies of the hydrogels were compared between before and after the alkaline hydrolysis treatment. Saponification of chitosan-g-poly(acrylamide) (chitosan-g-PAAm) with a hot sodium hydroxide solution gave rise to a high water absorbency. Swelling of the hydrogel samples in saline solution (0.15 mol/L NaCl, CaCl_2 and AlCl_3) was examined. Swelling capacity …
Synthesis And Vibrational Spectroscopic Study Of Some Metal(Ii) Halide And Tetracyanonickelate Complexes Of Isonicotinic Acid, Ahmet Ataç, Fehmi̇ Bardak
Synthesis And Vibrational Spectroscopic Study Of Some Metal(Ii) Halide And Tetracyanonickelate Complexes Of Isonicotinic Acid, Ahmet Ataç, Fehmi̇ Bardak
Turkish Journal of Chemistry
The M(IN)_2Ni(CN)_4 [where M: Cu, Mn, Zn, IN: Isonicotinic acid, abbreviated to M-Ni-IN] tetracyanonickelate and some metal halide complexes with the following stoichiometries: Cu(IN)X_2 (X:Br,I), Cd(IN)_2X_2, (X:Cl,Br), and Zn(IN)_4X_2 (X:Br,I) were synthesized for the first time. Their FT-IR spectra were reported in the 4000-400 cm^{-1} region. Vibrational assignments were given for all the observed bands. The analysis of the vibrational spectra indicates that there are some structure-spectrum correlations. For a given series of isomorphous complexes, the sum of the difference between the values of the vibrational modes of uncoordinated isonicotinic acid that were coordinated to the metal ion isonicotinic acid …
Synthesis Of Some New Functionalized Octasilsesquioxane Hybrid Nanoclusters. Iii. Potential Of The Octameric Clusters As Hydraulic Lubricating Fluids, Enock O. Dare
Turkish Journal of Chemistry
The reaction of suitable organic compounds such as \omega -halo-1-alkenes, allyltrichlorosilane or 2-methyl-3-butyn-2-ol in combination with a well-defined inorganic silsesquioxane, H_8Si_8O_{12} A cores, leads to covalently bound organic-inorganic hybrid materials in high yields. The hydraulic fluid properties of these viscous hybrid materials were evaluated and compared with those of some commercially available hydraulic fluids: Mobil EAL 224H, Super-V (AP) and Puroil SHO. The results showed that most silsesquioxane semi-liquids possess hydraulic fluid properties comparable to those of the 3 commercial lubricants.
A New Flame-Retardant Polyamide Containing Phosphine Oxide And N,N-(4,4-Diphenylether) Moieties In The Main Chain: Synthesis And Characterization, Khalil Faghihi
Turkish Journal of Chemistry
A new flame-retardant polyamide containing phosphine oxide moieties in the main chain was synthesized from the solution polycondensation reaction of bis(3-aminophenyl) phenyl phosphine oxide with N,N-(4,4-diphenylether) bis trimellitimide, using thionyl chloride, N-methyl-2-pyrolidone, and pyridine as condensing agents. This new polymer was obtained in high yield (92%), has high inherent viscosity (0.73 dL/g), and was characterized by elemental analysis, FT-IR spectroscopy, thermal gravimetric analysis (TGA and DTG), and solubility testing. Furthermore, another polyamide was prepared by the solution polycondensation reaction of N,N-(4,4-diphenylether) bis trimellitimide with 1,4-phenylene diamine, and its flame-retardant behavior was compared to that of the previous one.
Attempted Synthesis Of 1-Cyclohepta-1,2-Dien-1-Ylbenzene And Wurtz-Like Condensation Products In The Reaction Of 1-(2,3-Dibromocyclohept-1-En-1-Yl)Benzene With Zinc, Mustafa Ceylan, Yakup Budak, M. Burcu Gürdere
Attempted Synthesis Of 1-Cyclohepta-1,2-Dien-1-Ylbenzene And Wurtz-Like Condensation Products In The Reaction Of 1-(2,3-Dibromocyclohept-1-En-1-Yl)Benzene With Zinc, Mustafa Ceylan, Yakup Budak, M. Burcu Gürdere
Turkish Journal of Chemistry
7,7-Dibromo-1-phenylbicyclo[4.1.0]heptane 4 was synthesized and its thermal and silver ion-catalyzed rearrangements were studied. Alcohol 8 was converted to 1-(2,3-dibromocyclohept-1-en-1-yl)benzene 6. The zinc-mediated elimination of 1-(2,3-dibromocyclohept-1-en-1-yl)benzene 6 resulted in the formation of 2 isomeric Wurtz-like condensation products 15 and 16 (whose structural assignments were based on ^1H-and ^{13}C-NMR spectral data) instead of the expected 1-cyclohepta-1,2-dien-1-ylbenzene 14.
The Impact Of Polyacrylamide Molecular Weight On Its Adsorption Behavior At The Gold/Acidic Solution Interface, Dragica B. Chamovska, Toma P. Grchev, Maja V. Cvetkovska
The Impact Of Polyacrylamide Molecular Weight On Its Adsorption Behavior At The Gold/Acidic Solution Interface, Dragica B. Chamovska, Toma P. Grchev, Maja V. Cvetkovska
Turkish Journal of Chemistry
Adsorption isotherms for polyacrylamide (PAA) on polycrystalline gold, from sulfuric acid (potential range 0-2.0 V/she; 293 K), were obtained by means of cyclic voltammetry with simultaneous monitoring of the double-layer capacity. The Frumkin isotherm indicates that relatively strong attractive forces are present (a = 0.8-1.0), and the Gibbs energies range between 43 and 56 kJ mol^{-1}. The coverage (\theta) of the metal surface with polymer molecules depends on the molar concentration of PAA, as well as on its molecular weight, and the size of the statistical polymer coil in the solution (R_G = 7.49 \times 10^{-3} \times M_n^{0.64}/nm). The adsorption …
Simple Synthesis Of \Alpha -Oxime Derivatives Of 2-Ketomethyl Quinolines Under Mild And Heterogeneous Conditions, Javad Safari, Mehdi Adib, Firouzeh Sheibani, Zahra Sadeghi
Simple Synthesis Of \Alpha -Oxime Derivatives Of 2-Ketomethyl Quinolines Under Mild And Heterogeneous Conditions, Javad Safari, Mehdi Adib, Firouzeh Sheibani, Zahra Sadeghi
Turkish Journal of Chemistry
2-Ketomethyl quinolines are converted to their \alpha-oximinoketone derivatives in quantitative yields using sodium nitrite in the presence of silica sulfuric acid as nitrosating agent under mild and heterogeneous conditions.
Synthesis Of 1-Cyclohept-1,2-Dien-1-Yl Benzene From 1-(2-Iodo-, Chlorocyclohept-1-En-1-Yl)Benzene And 1-(2-Iodo-, Chlorocyclohept-2-En-1-Yl)Benzene: Its Trapping With Diphenylisobenzofuran, Mustafa Ceylan, Yakup Budak, Murat Ulukaya, M. Burcu Gürdere, Esra Findik
Synthesis Of 1-Cyclohept-1,2-Dien-1-Yl Benzene From 1-(2-Iodo-, Chlorocyclohept-1-En-1-Yl)Benzene And 1-(2-Iodo-, Chlorocyclohept-2-En-1-Yl)Benzene: Its Trapping With Diphenylisobenzofuran, Mustafa Ceylan, Yakup Budak, Murat Ulukaya, M. Burcu Gürdere, Esra Findik
Turkish Journal of Chemistry
The key compounds vinyl iodides 12a and 13a, for the generation of 1-cyclohept-1,2-dien-1-ylbezene (1), were synthesized from cycloheptanone (5). Bromobenzene was converted to the Grignard reagent, which was condensed with 5. Dehydration of alcohol 6 gave alkene 7. Hydroboration of 7 followed by oxidation with PCC afforded ketone 9, which was converted to hydrazone 10. Treatment of 10 with iodine resulted in the formation of 12a and 13a. The other precursors, 12b and 13b, were synthesized from the reaction of 9 with PCl_5. Reactions of 12a, b and 13a, b with KOtBu in a sealed tube at 185 °C gave …
Hydrothermal And Microwave-Assisted Synthesis Of Boroarsenate, Baso_4, Abdulhadi̇ Baykal, Ayten Evren
Hydrothermal And Microwave-Assisted Synthesis Of Boroarsenate, Baso_4, Abdulhadi̇ Baykal, Ayten Evren
Turkish Journal of Chemistry
BAsO_4 was previously synthesized by solid-state reactions at 800 °C and was characterized by X-ray powder diffraction. Now, we succeeded in preparing BAsO_4 from H_3BO_3 and As_2O_5 using hydrothermal synthesis by heating at 160 °C for 3 days (a single-phase product) and using microwave-assisted synthesis, which takes only 5 min to transform a solid mixture of As_2O_5 and (NH_4)_2B_4O_7.4H_2O into the crystalline titled compound (a single-phase product). The crystallinity of the products is higher than that of the solid-state synthesized product given in the literature. Its X-ray powder diffraction patterns, and both Raman and IR spectra were in good agreement …
A New Method For The Preparation Of Pyridazine Systems: Experimental Data And Semiempirical Pm3 Calculations, Di̇lek Ünal, Emi̇n Saripinar, Yunus Akçamur
A New Method For The Preparation Of Pyridazine Systems: Experimental Data And Semiempirical Pm3 Calculations, Di̇lek Ünal, Emi̇n Saripinar, Yunus Akçamur
Turkish Journal of Chemistry
The reactions of 4-benzoyl-5-phenyl-2,3-furandione (1a) and 4-(4-methoxybenzoyl)-5-(4-methoxyphenyl)-2,3-furandione (1b) with acyl hydrazines (2) (namely hydrazides) are reported. From these reactions, novel pyridazinone systems (3a-g) are obtained as well as the cyclization product of 3g at high temperature (4). The electronic properties and conformational parameters for these molecules, such as bond lengths, bond angles, torsion angles and atom charges, are calculated with a semiempirical PM3 method. In order to determine the mechanism of the reaction between the model furandion (R1) and formic hydrazide (R2), the electronic properties, conformational parameters and imaginary frequencies of the reactants, transition states and intermediates are calculated at …
Cerium(Iii) Ion-Selective Electrodes Based On 1,4,7-Trithiacyclononane, Hamid Reza Pouretedal, Abolfazl Semnani, Mohammad Hossein Keshavarz
Cerium(Iii) Ion-Selective Electrodes Based On 1,4,7-Trithiacyclononane, Hamid Reza Pouretedal, Abolfazl Semnani, Mohammad Hossein Keshavarz
Turkish Journal of Chemistry
Novel plasticized polymeric membrane (PPME) and coated platinum wire (CPWE) electrodes based on 1,4,7-trithiacyclononane and oleic acid, as a good lipophilic additive for highly selective determination of Ce^{3+} ions, have been developed. The electrodes exhibit a Nernstian slope of 19.4 mV/decade (for both electrodes) over a wide Ce^{3+} ion concentration range, from 5.0 \times 10^{-6}-5.0 \times 10^{-2} M and 1.0 \times 10^{-7}-1.0 \times 10^{-2} M for PPME and CPWE, respectively. The limits of detection were 3.5 \times 10^{-6} and 8.0 \times 10^{-8} M for PPME and CPWE, respectively. The electrodes possess a fast response time of 15 s, can be …
Synthesis, Spectroscopic (Ft-Ir, ^1h, ^{13}C, Mass Spectrometry), And Biological Investigation Of Five-Coordinated Germanium-Substituted Tricyclohexyl Antimony Dipropionates: Crystal Structure Of Tricyclohexylantimony Dibromide, Muhammad Kaleem Khosa, Muhammad Mazhar, Saqib Ali, Kieran C. Molloy, Sarim Dastgir, Farkhanda Shaheen
Synthesis, Spectroscopic (Ft-Ir, ^1h, ^{13}C, Mass Spectrometry), And Biological Investigation Of Five-Coordinated Germanium-Substituted Tricyclohexyl Antimony Dipropionates: Crystal Structure Of Tricyclohexylantimony Dibromide, Muhammad Kaleem Khosa, Muhammad Mazhar, Saqib Ali, Kieran C. Molloy, Sarim Dastgir, Farkhanda Shaheen
Turkish Journal of Chemistry
A series of five-coordinated germanium-substituted tricyclohexylantimony dipropionates have been synthesized and characterized by different instrumental techniques, such as elemental analyses, FT-IR, multinuclear NMR (^1H, ^{13}C) and mass spectrometry. These compounds have also been screened against different microbes and they showed good activity against different bacteria that was comparable to the reference drugs. The crystal structure of the precursor (C_6H_{11})_3SbBr_2 is reported here, which showed that the antimony atom in an asymmetric unit exists in trigonal bipyramidal geometry, having space group C2/c with the monoclinic crystal system.
The Effect Of Acid Digestion On The Recoveries Of Trace Elements: Recommended Policies For The Elimination Of Losses, Güler Somer, Arzu Nakişci Ünlü
The Effect Of Acid Digestion On The Recoveries Of Trace Elements: Recommended Policies For The Elimination Of Losses, Güler Somer, Arzu Nakişci Ünlü
Turkish Journal of Chemistry
Digestion of biological materials is very important for trace element determinations. Although the microwave technique is mostly used, there are cases where open wet digestion is needed. This study examined the optimum conditions for the minimum loss of trace elements during the wet digestion of a sample. The effect of acid composition and digestion time for about 21 ions was investigated. The trace element concentrations were determined by differential pulse polarography. For the digestion procedure, a HClO_4-HNO_3 mixture was used for the first step and, after its evaporation (60 min), HCl was added as the second step, since in some …
Secondary Metabolites From Phlomis Syriaca And Their Antioxidant Activities, Ü. Şebnem Harput, İhsan Çaliş, İclal Saracoğlu, Ali̇ Arslan Dönmez, Akito Nagatsu
Secondary Metabolites From Phlomis Syriaca And Their Antioxidant Activities, Ü. Şebnem Harput, İhsan Çaliş, İclal Saracoğlu, Ali̇ Arslan Dönmez, Akito Nagatsu
Turkish Journal of Chemistry
An iridoid glucoside, lamiide (1); 4 phenylethanoid glycosides, acteoside (2), \beta-OH acteoside (3), leucosceptoside A (4) and samioside (5); a caffeic acid ester, chlorogenic acid (6); 2 flavone glucosides, luteolin-7-O-glucopyranoside (7) and chrysoeriol-7-O-glucopyranoside (8); and a flavanone aglycone, naringenin (9), were isolated from the aerial parts of Phlomis syriaca. The structures of the isolated compounds were elucidated by means of spectroscopic (UV, IR, 1D- and 2D-NMR, and FAB-MS) methods. Free radical scavenging activity of the isolated compounds was determined using the radical 2,2-diphenyl-1-picrylhydrazyl (DPPH), spectroscopically.
Iridoid, Flavonoid, And Phenylethanoid Glycosides From Wiedemannia Orientalis, Zühal Güvenalp, Hi̇lal Özbek, Türesi̇n Ünsalar, Cavi̇t Kazaz, L. Ömür Demi̇rezer
Iridoid, Flavonoid, And Phenylethanoid Glycosides From Wiedemannia Orientalis, Zühal Güvenalp, Hi̇lal Özbek, Türesi̇n Ünsalar, Cavi̇t Kazaz, L. Ömür Demi̇rezer
Turkish Journal of Chemistry
Five iridoid glycosides, lamiide, ipolamiide, ipolamiidoside, 6\beta-hydroxyipolamiide, and 5-hydroxy-8-epi-loganin; 5 flavonoid glycosides, apigenin 7-O-\beta-glucopyranoside, luteolin 5-O-\beta- glucopyranoside, isorhamnetin 3-O-rutinoside, quercetin 3-O-rutinoside, and apigenin 7-O-(6''-O-trans-p-coumaroyl) \beta-glucopyranoside; and a phenylethanoid glycoside, acteoside (= verbascoside), were isolated from the aerial parts of Wiedemannia orientalis (Lamiaceae). Their structures were identified using spectral methods (UV, 1D- and 2D-NMR, and EI-MS).
The Effects Of Professional Development To Create Standards -Based Curriculum On Student Achievement In Fourth And Fifth Grade Mathematics Classrooms, Martin Amy Mcbride
The Effects Of Professional Development To Create Standards -Based Curriculum On Student Achievement In Fourth And Fifth Grade Mathematics Classrooms, Martin Amy Mcbride
All-Inclusive List of Electronic Theses and Dissertations
The National Council of Teachers of Mathematics determined there were several concepts or standards†needed for quality teaching of math While few dispute their importance, little support and resources are provided to help teachers understand and meet these standards. Long term professional development which focuses on how to teach with these standards could play a crucial role in improving the academic achievement of students. In this study, professional development opportunities were provided for teachers to explore the various elements of mathematics and develop a better understanding of how to teach them. The main purpose of the research was to study …
Modeling Uncertainty In Mountain Pine Beetle Management Systems, Anthony L. Alfano
Modeling Uncertainty In Mountain Pine Beetle Management Systems, Anthony L. Alfano
Theses and Dissertations (Comprehensive)
This study attempts to introduce elements of data uncertainty into the Shore and Safranyik model for approximating risk and susceptibility ratings for Mountain Pine Beetle attack in the Morice Forest District of British Columbia, Canada. Data uncertainty is introduced into the modeling procedure by introducing attribute uncertainty and spatial (boundary) vagueness into representations of Forest Inventory Polygon data, an essential component of the Shore and Safranyik modeling system, for the purposes of assessing the effects of uncertainty on the results of the Shore and Safranyik susceptibility modeling procedure. Introducing uncertainty into the forest inventory data is done by introducing spatial …
An Investigation Into The Spatial And Temporal Movement Of The Sand Dunes In The West Lake Ecosystem Of Sandbanks Provincial Park And The Implications For Management (Ontario), Jayson A. Childs
Theses and Dissertations (Comprehensive)
Sandbanks Provincial Park is located on the northern shore of eastern Lake Ontario approximately 150km east of Toronto. The park is located on the southwestern shore of Prince Edward County in Hallowell Township and the research site was located on the larger of the two baymouth barriers the park protects. The research into aeolian sediment transport was carried out over twelve months in 2003--2004 on the Wellington Baymouth barrier. Vegetated sand dunes are sensitive geomorphic systems and when the protective cover is damaged and removed, changes are inevitable. The study examined variations in the amount of sediment transport in different …
An Analysis Of Community Forest Implementation In British Columbia, Canada, Ryan C. Bullock
An Analysis Of Community Forest Implementation In British Columbia, Canada, Ryan C. Bullock
Theses and Dissertations (Comprehensive)
The community forest is increasingly seen as an alternative to industrial forestry for its perceived potential to mitigate conflict in forest resource management and planning. Theoretically, a community-based approach affords the chance to assert local values, provide local benefits, and manage resources differently than established top-down approaches. Yet practical examples of community forest initiatives in Canada reveal a host of constraints. This research uses a multiple case study design to investigate the motivations for and challenges to implementing community forests in British Columbia, Canada. Observations are drawn from four case studies (Denman Island, Malcolm Island, Cortes Island, and Creston) in …
Implementing The Oak Ridges Moraine Conservation Plan: A Case Study Of Initial Implementation Experiences, Ryan Dore
Theses and Dissertations (Comprehensive)
Implementing an ecologically-based land use plan presents a variety of challenges. To gain insight into these challenges, this study focuses on the experiences of actor intimately involved in implementing the Oak Ridges Moraine Conservation Plan. To begin, a conceptual overview of regional planning/growth management, ecosystem-based management, and policy implementation literature and concepts are presented, along with a contextual overview of the Oak Ridges Moraine Conservation Plan. Following the conceptual and contextual overviews, Hanna’s (2006) framework addressing eight obstacles to policy implementation is used to discuss and analyze the information collected during the interview process. Lastly, seven lessons for implementing an …