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Vapor-Liquid Phase Equilibria Using Monte Carlo Wang-Landau Simulations, Tsvetan Aleksandrov

Theses and Dissertations

The experimental determination of the critical point of metals is inherently connected with difficulties of measuring large temperatures and pressures. On the other hand, that of straight alkane chains larger than ten carbon atoms and branched chains larger than eight atoms is burdensome due to decomposition of the molecules while in the vapor phase. Therefore molecular simulations stand as an appropriate alternative for determining the critical point and phase coexistence properties of these fluids. Most simulation methods that are apt for this task rely on particles insertion and deletion moves that can significantly complicate the simulation, since high density in …

Establishment Of Photo-Activated Localization Microscopy (Palm) For Imaging Signaling Complexes On The Surfaces Of Cells, Bradley E. Iverson

The Journal of Undergraduate Research

Photoactivated Localization Microscopy (PALM) permits visualization of single molecules inside cells at ~10 times the resolution of existing optical microscopes. The 10-50 nanometer resolution afforded by PALM is ideally suited to studying the organization of receptor signal transduction occurring on the surfaces of cells. Initial efforts presented here focused on cells expressing Fc receptor fused to photoactivatable green fluorescent protein (paGFP). A small fraction of the paGFP molecules were photoactivated using a 405 nm laser pulse, resulting in single molecule spots that could then be imaged using 488 nm laser excitation until they photobleached. Both lasers illuminated the sample through …

Anticancer Activity And Biophysical Reactivity Of Copper Complexes Of 2-(Benzo[D][1,3]Dioxol-5-Ylmethylene)-N-Alkylhydrazinecarbothioamides, Floyd A. Beckford, Jeffrey Thessing, Alyssa Stott, Alvin A. Holder, Oleg G. Poluektov, Liya Li, Navindra P. Seeram

Faculty Publications

A series of copper complexes were synthesized from benzo[d][1,3]dioxole-5-carbaldehyde (piperonal) thiosemicarbazones (RHpTSC where R = H, CH3, C2H5 or C6H5 (Ph)). The complexes show interesting variations in geometry depending on the thiosemicarbazone; a dinuclear complex [Cu(HpTSC)Cl]2, a mononuclear complex [Cu(RHpTSC)2Cl2] (R = CH3 or C2H5) and another mononuclear complex [Cu(PhHpTSC)(PhpTSC)Cl] was generated. The complexes bind in a moderately strong fashion to DNA with binding constants on the order of 10⁴ M^{− 1}. They are also strong binders of human serum albumin with binding constants near 10⁴ M^{− 1}. The complexes show good in vitro …

Biosynthesis Of Marineosin, A Spiroaminal Undecylprodiginine Natural Product, Shaimaa Mohamed Salem

Dissertations and Theses

Marineosins A and B are two spiroaminal-ring containing tripyrrole compounds isolated from the marine actinomycete, Streptomyces CNQ-617, and were found to possess potent and selective cytotoxic activity against leukemia and melanoma. Marineosins belong to the prodiginines class of natural products, examples of which are undecylprodiginine and streptorubin B. Unlike marineosins, prodiginines structures are characterized by the presence of fully conjugated tripyrrole nucleus linked to an alkyl chain (that lacks any oxygen). Cyclic prodiginines arise from an oxidative cyclization of the alkyl chain onto the tripyrrole, a step catalyzed by Rieske-oxygenase like enzymes such as RedG. The biosynthesis of prodiginines is …

Understanding The Emission From Semiconductor Nanoparticles, Beth Ann Manhat

Dissertations and Theses

This dissertation describes the synthesis and characterization of fluorescent semiconductor nanoparticles (NPs) in order to optimize their biomedical utility for imaging and sensing applications. While both direct and indirect bandgap semiconductor NPs have been studied, control over their emission properties vary. Quantum confinement (QC), which primarily controls the emission wavelength of nanosized semiconductors, dictates that as the size of semiconductor NPs decrease, the magnitude of the bandgap increases, resulting in changes in the observed emission wavelength: smaller NPs have a larger bandgap, and thus a bluer emission. However, surface, interfacial, or shell defects can act as non-radiative or radiative recombination …

Synthesis Of The Novel Benzothiazole Compounds From 7-Benzylidenebicyclo [3.2.0] Hept-2-En-6-Ones And 2-Aminobenzenethiol, Esra Findik

Turkish Journal of Chemistry

Synthesis of the 2-(2-styrylcyclopent-3-enyl)benzo-[d]thiazoles (6a-i) is reported for the first time. Reaction of 7-benzylidenebicyclo [3.2.0] hept-2-en-6-ones (3a-i) and 2-aminobenzenethiol (4) in the presence of p-TsOH as a catalyst, in ethanol under reflux, resulted in the formation of novel 2-(2-styrylcyclopent-3-enyl)benzo[d]thiazoles in high yields.

One-Pot Synthesis Of Fully Substituted 1,3,4-Oxadiazole Derivatives From Aromatic Carboxylic Acids, Cyclobutanone And N-Isocyaniminotriphenylphosphorane, Mohsen Valizadeh Holagh, Abel Mohammadali Oglu Maharramv, Mirza Aliakbar Oglu Allahverdiyev, Ali Ramazani, Yavar Ahmadi, Ali Souldozi

Turkish Journal of Chemistry

Reactions of N-isocyaniminotriphenylphosphorane with cyclobutanone in the presence of aromatic (or heteroaromatic) carboxylic acids proceeded smoothly at room temperature and in neutral conditions to afford sterically congested 1-(5-aryl-1,3,4-oxadiazol-2-yl)- 1-cyclobutanol derivatives in high yields. The reaction proceeded smoothly and cleanly under mild conditions and no side reactions were observed. The structures of the products were deduced from their IR, ^1HNMR, and ^{13}CNMR spectra, and mass spectrometry.

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 …

Synthesis Of Some New Urea And Thiourea Derivatives And Evaluation Of Their Antimicrobial Activities, Yildiz Gülkok, Tuba Bi̇çer, Fatma Kaynak Onurdağ, Selda Özgen, Mustafa Fethi̇ Şahi̇n, Deni̇z Songül Doğruer

Turkish Journal of Chemistry

In the present study, 18 new compounds were synthesized, 9 of which were urea (9a-e, 10a-d) while the others were thiourea (11a-e, 12a-d) derivatives. These derivatives were prepared by the reaction of 6-amino-5-nonsubstituted/chloro-3-methyl-2(3H)- benzoxazolones used as key intermediates with the appropriate isocyanates and isothiocyanates. The chemical structures of new compounds were confirmed by ^1H-NMR, mass, and elemental analysis. The synthesized compounds were screened for their antibacterial and antifungal activities against some pathogenic strains. Compounds 9a, 9b, 9e, 10a, and 10c, urea derivatives, and compounds 12a and 12d, thiourea derivatives, exhibited a relatively good inhibitory profile against E. coli, with a …

Antimicrobial Properties And Dna Interactions Studies Of 3-Hetarylazoquinoline-2,4-Diol Compounds, Fatma Öztürk, Leyla Açik, İzzet Şener, Fi̇kret Karci, Emi̇ne Kiliç

Turkish Journal of Chemistry

The purpose of the present study was to evaluate the antimicrobial effects of 3-hetarylazoquinoline-2,4-diols (19), having substituted or unsubstituted thiazole, benzothiazole, benzimidazole, triazole, isoxazole, and thiadiazole moieties at the 3-position, on bacterial and yeast strains. In addition, compounds and DNA interaction with pUC18 plasmid DNA were studied. The biological effects of these molecules were compared with potential antibiotics ampicillin,~chloramfenicol (for bacteria), and ketoconozole (for yeast). According to the results, all compounds except 8 have mild to moderate activity against some of the bacterial strains tested, and none of the compounds have activity against the fungi C. tropicalis and C. albicans. …

Synthesis And Antimicrobial Evaluation Of Some Annelated Phthalazine Derivatives And Acyclo C-Nucleosides From 1-Chloro-4-(2,4,6-Trimethylphenyl) Phthalazine Precursor, Maher Abdel Aziz El-Hashash, Ahmed Youssef Soliman, Ibrahim Essam Elshamy

Turkish Journal of Chemistry

A highly efficient and versatile synthetic approach to the synthesis of annelated phthalazine derivatives viz. 1,2,4-triazolo [3,4-a]phthalazine 11a,b, 14, 18, 19a,b, 29-31, 33, 1,2,4-triazino [3,4-a]phthalazine 25a,b-28, 1,3,5-triazino[4,3-a]phthalazine 22, tetrazolo[5,1-a] phthalazine 23, imidazophthalazine 9a,b,15, and pyrimidinophthlazine 6, 10, 16, 17, 20 is presented. Moreover, acyclo C-nucleoside and double headed acyclo C-nucleoside of 1,2,4-triazolo[3,4-a]phthalazine 12, 13 were obtained via heterocyclization reaction of 1-chloro-4-(2,4,6-trimethylphenyl) phthalazine (4) with gluconic acid hydrazide and galactaric acid bis hydrazide, respectively. The new compounds were synthesized with the objective of studying their antimicrobial activity.

Synthesis, Anti-Inflammatory, Antiplatelet And In Silico Evaluations Of (E)-3-(3-(2,3-Dihydro-3-Methyl-2-Oxo- 3h-Benzoxazole-6-Yl)-1-Phenyl-1h-Pyrazole- 4-Yl)Acrylamides, Sultan Baytaş, Ni̇lüfer Nermi̇n Turan Dural, Yeşi̇m Özkan, Hasan Bolkan Şi̇mşek, Türki̇z Gürsel, Serdar Ünlü

Turkish Journal of Chemistry

A series of (E)-3-(3-(2,3-dihydro-3-methyl-2-oxo-3H-benzoxazole- 6-yl)-1-phenyl-1H-pyrazole-4-yl)acry- lamides (7a--k) were synthesized and evaluated for their in vitro inhibitory activities on COX-1 and COX-2 isoforms using a human whole blood assay as well as their antiplatelet profile against human platelet aggregation using arachidonic acid as agonists. Among the synthesized derivatives 7a--k, especially compound 7g exhibited dual anti-inflammatory and antiplatelet activity with selective COX-2 inhibition.

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 …

Synthesis, Characterization, And Antioxidant Activities Of New Trisubstituted Triazoles, Kemal Sancak, Yasemi̇n Ünver, Di̇lek Ünlüer, Esra Düğdü, Gülcan Kör, Fati̇h Çeli̇k, Emrah Bi̇ri̇nci̇

Turkish Journal of Chemistry

A series of new 4-(3,4dimethoxyphenethyl)-3,5-akyl/aryl-4H- 1,2,4-triazoles (3a-g) were obtained by reaction of ethyl N'-(alkylidene/arylidene)hydrazonate (1) and 2-(3,4-dimethoxy phenyl)ethanamine (2). Compounds 4d, e, and g were synthesized from the reaction of corresponding compounds 3d, e, and g with BBr_3, respectively. The 10 new compounds synthesized were characterized by elemental analyses, IR, ^1H-NMR, and ^{13}C-NMR spectral data. The structure of compound 3g was inferred through IR, ^1H-, ^{13}C-NMR, elemental analyses, and X-ray spectral techniques. In addition, the newly synthesized chemicals were screened for their antioxidant properties. Among the chemicals tested, 4d, e, and g exhibited the highest degree of antioxidant activity.

Simultaneous Determination Of Dopamine, Uric Acid, And Tryptophan Using An Mwcnt Modified Carbon Paste Electrode By Square Wave Voltammetry, Hadi Beitollahi, Alireza Mohadesi, Saeedeh Khalilizadeh Mahani, Hassan Karimi Maleh, Ali Akbari

Turkish Journal of Chemistry

A highly sensitive method was investigated for the simultaneous determination of dopamine (DA), uric acid (UA), and tryptophan (TRP) using a multiwall carbon nanotubes/5-amino-3',4'-dimethoxy-biphenyl-2-ol modified carbon paste electrode (5ADMBCNPE). The 5ADMBCNPE displayed excellent electrochemical catalytic activities towards the oxidation of DA, UA, and TRP. The electrochemical profile of the proposed modified electrode was analyzed by cyclic voltammetry (CV), which showed a shift in the oxidation peak potential of DA at 160 mV to a less positive value compared with an unmodified carbon paste electrode. Square wave voltammetry (SWV) in 0.1 M phosphate buffer solution (PBS) at pH 7.0 was performed …

Reduction, Mannich Reaction And Antimicrobial Activity Evaluation Of Some New 1,2,4-Triazol-3-One Derivatives, Seda Fandakli, Serap Başoğlu, Hakan Bektaş, Meltem Yolal, Ahmet Demi̇rbaş, Şengül Alpay Karaoğlu

Turkish Journal of Chemistry

Ethyl[4-arylmethyleneamino-3-(4-metylphenyl)-5-oxo-4,5-dihydro- 1H-1,2,4-triazole-1-yl]acetates (3a-e and 10a-d) were obtained starting from 4-amino-2,4-dihydro-3H-1,2,4-triazol-3-ones (1 and 9) in 2 steps. The treatment of 3a-e with NaBH_4 resulted in the formation of 3 kinds of product incorporating carboxcilic acid (4a-c) or alcohol (5a-e) functionality. [4-{[(4-Methoxyphenyl)methylene]amino}- and 4-{[pyridin-4-ylmethylene]amino}-3-(4-methylphenyl)-5-oxo-4,5-dihydro-1H- 1,2,4-triazole-1-yl] acetic acids (6a, 6e) were obtained by the hydrolysis of the corresponding esters (5a-5e). The treatment of 6a with NaBH_4 caused the reduction of only the imine bond; the carboxyl group remained unchanged. Then this carboxylic acid was converted to the corresponding hydrazide (8) in 2 steps by reaction with ethanol and hydrazine hydrate, respectively. The synthesis …

A Novel Soluble Phthalocyanine Capable Of Binding Four Boronic Esters, Şennur Özçeli̇k, Gülnur Keser Karaoğlan, Gülşah Gümrükçü, Ahmet Gül

Turkish Journal of Chemistry

A novel Zn phthalocyanine bearing 4 salicylideniminophenyloxy substituents on peripheral positions was synthesized from the reaction of 4-aminophenoxy substituted phthalocyanine and salicylaldehyde. The condensation reaction of salicylidene Schiff base groups and benzeneboronic acid produced a new phthalocyanine carrying benzeneboronic acid ester derivatives as substituents. Ethoxy groups were bound to boronic acid as a second ligand. The presence of B-N bond interactions enhanced the stability of this boronated phthalocyanine derivative, which exhibited sufficient air stability during the purification and characterization processes. The novel compounds were characterized by using elemental analysis, IR, ^1H-NMR, ^{11}B-NMR, ^{13}C-NMR, UV-Vis and MALDI-TOF MS spectral data.

Evaluation Of A Wide Rim Phosphorylated Calix[4]Arene's Properties As A Sensory Molecule In An Er(Iii)-Pvc Membrane Sensor, Abbas Ali Zamani, Massoumeh Parinejad, Fataneh Jamali, Mohammad Reza Yaftian, Dominique Matt

Turkish Journal of Chemistry

This study concerns the evaluation of ionophoric properties of a functionalized calix[4]arene, named 5,17-bis(diphenylphosphinoyl)- 25,26,27,28-tetrapropoxycalix[4]arene (Calix), by its application as a sensing material in an erbium(III)-PVC membrane potentiometric sensor. A membrane formed by 30% PVC, 65% dioctyl phthalate (DOP) as plasticizing solvent mediator, 2% sodium tetraphenyl borate (NaTPB) as ion excluder, and 3% of Calix as ionophore shows the best performance of the sensor. The prepared sensor presents a nearly Nernstian response (a slope of 20.0 \pm 0.5 mV/decade) over a concentration range of 1 \times 10^{-7}--1 \times 10^{-3} M of erbium ions, with a limit of detection of 3.8 …

Quantitative Analysis Of Some Important Metals And Metalloids In Tobacco Products By Inductively Coupled Plasma-Mass Spectrometry (Icp-Ms), Syed Ghulam Musharraf, Muhammad Shoaib, Amna Jabbar Siddiqui, Muhammad Najam-Ul-Haq, Aftab Ahmed

Pharmacy Faculty Articles and Research

Background: Large scale usage of tobacco causes a lot of health troubles in human. Various formulations of tobacco are extensively used by the people particularly in developing world. Besides several toxic tobacco constituents some metals and metalloids are also believed to pose health risks. This paper describes inductively coupled plasma-mass spectrometric (ICP-MS) quantification of some important metals and metalloids in various brands of smoked, sniffed, dipped and chewed tobacco products.

Results: A microwave-assisted digestion method was used for sample preparation. The method was validated by analyzing a certified reference material. Percentage relative standard deviation (% R.S.D.) between recovered …

A New, Simple, Green And One-Pot Four-Component Synthesis Of Bare And Poly(Α, Γ, L-Glutamic Acid) Capped Silver Nanoparticles, Magdalena Stevanović, Igor Savanović, Vuk Uskoković, Srečo D. Škapin, Ines Bračko, Uroš Jovanović, Dragan Uskoković

Pharmacy Faculty Articles and Research

A simple and green chemical method has been developed to synthesize stable bare and capped silver nanoparticles based on the reduction of silver ions by glucose and capping by poly(α,γ,Lglutamic acid) (PGA). The use of ammonia during synthesis was avoided. PGA has had a dual role in the synthesis and was used as a capping agent to make the silver nanoparticle more biocompatible and to protect the nanoparticles from agglomerating in the liquid medium. The synthesized PGA-capped silver nanoparticles in the size range 5–45 nm were stable over long periods of time, without signs of precipitation. Morphological examination has shown …

A Greener Synthesis Of 2-Aminochromenes In Ionic Liquid And Evaluation Of Their Antiproliferative Activities, M. Sudershan Rao, Bhupender S. Chhikara, Rakesh Tiwari, Amir Nasrolahi Shirazi, Keykavous Parang, Anil Kumar

Pharmacy Faculty Articles and Research

An improved simple and facile synthesis of chromene derivatives by employing threecomponent one-pot condensation reaction of β-naphthol, aromatic aldehydes, and malononitrile in ionic liquids is described.

Mining Functional Subgraphs From Cancer Protein-Protein Interaction Networks, Ru Shen, Nalin Goonesekere, Chittibabu Guda

Faculty Work

Background: Protein-protein interaction (PPI) networks carry vital information about proteins’ functions. Analysis of PPI networks associated with specific disease systems including cancer helps us in the understanding of the complex biology of diseases. Specifically, identification of similar and frequently occurring patterns (network motifs) across PPI networks will provide useful clues to better understand the biology of the diseases.

Results: In this study, we developed a novel pattern-mining algorithm that detects cancer associated functional subgraphs occurring in multiple cancer PPI networks. We constructed nine cancer PPI networks using differentially expressed genes from the Oncomine dataset. From these networks we …

Kinetic Studies On Lactonization Of Quinone Propionic Acid Derivatives For The Development Of Redox Responsive Liposomes, K. L. Iresha Sampathi Perera

LSU Master's Theses

ABSTRACT Stimuli-responsive liposome systems that utilize endogenous triggers of tumor microenvironment have generated great attention in recent drug delivery research. Among such formulations, redox-responsive liposomes seem highly promising for cancer treatment due to their potential to release high drug concentrations upon reduction (by reductase enzymes). The research described in this thesis involved the evaluation of kinetics of trimethyl-lock quinone propionic acid reduction and lactonization, which accounts for payload release from trimethyl-lock quinone propionic acid-decorated liposomes. To achieve the ultimate goal of this research, several trimethyl-lock quinone propionic acid-based amide compounds were synthesized and characterized. Kinetic studies were carried out with …

Microwave-Assisted Synthesis, Spectroscopy, And Crystal Structures Of [(H_2-(4,4'-Bipy)]^{2+} [Cr_2o_7]^{2-} And One-Dimensional Polymeric {[Mn(4,4'-Bipy)(Cr_2o_7)(H_2o)_2]\}_N Compounds, Hirihattaya Phetmung, Munee Wateh, Chaveng Pakawatchai

Turkish Journal of Chemistry

A compound (1), [H_2-(4,4'-bipy)]^{2+}[(Cr_2O_7)]^{2-} and a metal organic-inorganic coordination framework (2), [Mn(4,4'-bipy)(Cr_2O_77)(H_2O)_2] (4,4'-bipy=4,4' -bipyridine) were successfully synthesized by microwave method. Their characterization was performed by single crystal X-ray crystallography and FT-IR spectroscopy. The crystal structure of 1 revealed a diprotonated 4,4'-bipyridium dichromate compound while compound 2 is an onedimensional (1D) polymer in which (Cr_2O_7)^{2-} acts as a bridging ligand supporting the formation of infinite {[Mn(4,4'-bipy)(Cr_2O_7)(H_2O)_2]}_n polymeric chains. The geometry of the 4,4'-bipy ring in 1 is typical coplanar, but twists in 2. In the free molecule 1, dichromate ligand adopts an eclipsed conformation, but adopts a staggered conformation in complex. …

Synthesis, Structural Characterization, And Benzyl Alcohol Oxidation Activity Of Mononuclear Manganese(Ii) Complex With 2,2'-Bipyridine: [Mn(Bipy)_2(Clo_4)_2], İbrahi̇m Kani̇, Mehmet Kurtça

Turkish Journal of Chemistry

A manganese(II) complex of 2,2'-bipyridine (bipy) was synthesized and characterized by X-ray diffraction, IR, and UV-vis spectroscopy. The activity of the complex was tested for oxidation of benzyl alcohols using t-BuOOH as an oxidant in organic solvents and in an organic/water biphasic system (hexane/H_2O, toluene/H_2O). The effect of solvent, temperature, oxidant, and some additives (KBr, N(C_4H_9)Br, and N-bromosuccinimide) on the oxidation of benzyl alcohol is reported. The results show that benzyl alcohol was selectively converted to benzaldehyde in 71.9% yield within 4 h in acetonitrile. Control experiments performed without catalyst and the corresponding metal salt as catalyst produced no benzaldehyde …

Capturing Motion, Allison Marsh

Section 3: Imaging the Fast Moving

No abstract provided.

Images From The Exhibit, Page 2, Allison Marsh

Handouts

No abstract provided.

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 …

Determination Of Cadmium In High Salt Content Matrices By Flow Injection Cold Vapor Atomic Absorption Spectrometry, Orkun Alp, Hakan Demi̇röz, Osman Yavuz Ataman, Nusret Ertaş

Turkish Journal of Chemistry

Flow injection cold vapor atomic absorption spectrometry (FI-CVAAS) was used for determination of cadmium in high salt matrices such as dialysis concentrates and textile leach solutions. The parameters such as acidity, concentration of reducing agent, reaction coil length, and carrier gas flow rate were investigated to obtain the best sensitivity. No significant background signal was observed even at high salt concentrations. Under the optimized conditions the limit of detection value (3s_b m^{-1}, where s_b is the standard deviation of the blank signals and m is the slope of the calibration graph) was found to be 0.05 ng mL^{-1} for an …

Novel Biologically Active Glycosides From The Aerial Parts Of Cephalaria Gazipashensis, Nazli Böke Sarikahya, Süheyla Kirmizigül

Turkish Journal of Chemistry

Two new triterpene glycosides, 3-O-\beta-D-glucopyranosyl- (1\to 4)-\beta-D-xylopyranosyl-(1\to 3)-\alpha-L-rhamnopyranosyl- (1\to 3)-\alpha-L-arabinopyranosyl olean-12-ene 28-O-\beta -D- glucopyranosyl-(1\to 6)-\beta-D-glucopyranosyl ester (gazipashoside A, 1) and 3-O-\beta-D-glucopyranosyl-(1\to 4)-\beta-D-xylopyranosyl- (1\to 3)-\alpha-L-rhamnopyranosyl-(1\to 2)-\alpha-L-arabinopyranosyl hederagenin 28-O-\beta -D-glucopyranosyl-(1\to 6)-\beta-D-glucopyranosyl ester (gazipashoside B, 2), were isolated together with 11 known compounds including 7 triterpene, 1 flavonoid, and 3 iridoidal metabolites from the aerial parts of Cephalaria gazipashensis (Dipsacaceae). The structures of all compounds were elucidated by extensive evaluation of the spectroscopic data (1D- and 2D- NMR, HRESI-MS), as well as chemical examinations. The antimicrobial effects of all pure compounds were tested against gram-positive and gram-negative bacteria. The results indicated that the …