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Convenient Synthesis And Anion Recognition Property Of Acylhydrazone-Based Molecular Tweezer Receptors, Hai-Xian Ren, Ming-Gen Zhao, Ying-Jin Wang Jan 2010

Convenient Synthesis And Anion Recognition Property Of Acylhydrazone-Based Molecular Tweezer Receptors, Hai-Xian Ren, Ming-Gen Zhao, Ying-Jin Wang

Turkish Journal of Chemistry

Three acylhydrazone-based compounds were designed as novel neutral sensors for anions, and synthesized by simple steps in good yields. Their anion recognition properties were studied by UV-vis and ^1H-NMR spectroscopy. The results showed that the receptors 1, 2, and 3 all had a better selectivity for F^- and CH_3COO^-, but no evident binding with Cl^-, Br^-, I^-, NO_3^-, H_2PO_{4}^-, or HSO_{4}^-. The results indicated that anion recognition was achieved via convergent hydrogen bond interactions from acylhydrazone functionality on the side arms. The UV-vis data indicated that a 1:1 stoichiometry complex was formed between compounds 1, 2, or 3 and anions. …


Synthesis, Spectroscopic Characterization, Mass Spectrometry, And Crystal Structure Of N-{[(4-Bromophenyl)Amino]Carbonothioyl}Benzamide, Sohail Saeed, Naghmana Rashid, Moazzam Bhatti, Peter Jones Jan 2010

Synthesis, Spectroscopic Characterization, Mass Spectrometry, And Crystal Structure Of N-{[(4-Bromophenyl)Amino]Carbonothioyl}Benzamide, Sohail Saeed, Naghmana Rashid, Moazzam Bhatti, Peter Jones

Turkish Journal of Chemistry

N-{[(4-bromophenyl)amino]carbonothioyl}benzamide was synthesized and characterized by IR, ^1H- and ^{13}C-NMR, mass spectrometry, and elemental analysis. The crystal structure was determined from single crystal X-ray diffraction data. It crystallizes in monoclinic space group P2_1/n with unit cell dimensions a = 13.822(3) Å, b = 5.927(2) Å, c = 16.642(3) Å, and \beta = 103.963(3)°. There is a strong intramolecular hydrogen bond of the type N__H \Lambda O, with an H\Lambda O distance of 2.6129 (11) Å. The mass fragmentation pattern is also discussed.


Reactions Of 4-Benzoyl-1,5-Diphenyl-1h-Pyrazole-3- Carboxylic Acid Chloride With Various Hydroxylamines And Carbazates, Eli̇f Korkusuz, İsmai̇l Yildirim Jan 2010

Reactions Of 4-Benzoyl-1,5-Diphenyl-1h-Pyrazole-3- Carboxylic Acid Chloride With Various Hydroxylamines And Carbazates, Eli̇f Korkusuz, İsmai̇l Yildirim

Turkish Journal of Chemistry

The 1H-pyrazole-3-carboxylic acid 2 was converted via reactions of its acid chloride 3 with various hydroxylamine 4a-f and carbazate derivatives 8a-c into the corresponding novel N-substituted-4-benzoyl-1,5-dipenyl-1H-pyrazole-3-carboxamides 5a-c, N,N-disubstituted-4-benzoyl-1,5-diphenyl-1H-pyrazole-3-carboxylates 6d,e, 4-benzoyl-N-{[(4-benzoyl-1,5-diphenyl-1H-pyrazol-3-yl)carbonyl]oxy}- N-methyl-1,5dip- henyl-1H-pyrazole-3-carboxamide (7), and 4-benzoyl-N'-(alkoxycarbonyl)-1,5-diphenyl-1H-pyrazole-3-car- bohydrazides 9a,b and 10, respectively, in good yields (65\%-90\%). The reactions of 3 with 4 and 8 in xylene for 8-15 h with catalytic amounts of base led to the formation of the products 5-7, 9, and 10. The structures of all new synthesized compounds were established by the ^{13}C-NMR, ^1H-NMR, IR spectroscopic data, and elemental analyses.


Biotransformation Of Danazol By Fusarium Solani And Gibberella Fujikuorii, And Prolyl Endopeptidase Inhibition Studies Of Transformed Products, Azizuddin Shaikh, Muhammad Iqbal Choudhary Jan 2010

Biotransformation Of Danazol By Fusarium Solani And Gibberella Fujikuorii, And Prolyl Endopeptidase Inhibition Studies Of Transformed Products, Azizuddin Shaikh, Muhammad Iqbal Choudhary

Turkish Journal of Chemistry

Biotransformation of danazol (17\beta-hydroxy-17\alpha-pregna-2,4-dien-20-yno-[2,3-d] isoxazole) (1) on fermentation with Fusarium solani yielded 17\beta-hydroxy-2-(hydroxymethyl)-17\alpha -pregn-4-en-20-yn-3-one (2) and 17\beta -hydroxy-2-(hydroxymethyl)-17\alpha-pregna-1,4-dien-20-yn-3-one (3), while the fermentation of 1 with Gibberella fujikuorii yielded compound 2 only. The structures of these compounds were deduced on the basis of modern spectroscopic techniques. Prolyl endopeptidase inhibition activities of danazol (1) and its transformed products 2 and 3 are also studied.


Comparative Essential Oil Analysis Of Geranium Sylvaticum Extracted By Hydrodistillation And Microwave Distillation, Nuran Kahri̇man, Gonca Tosun, Hasan Genç, Nuretti̇n Yayli Jan 2010

Comparative Essential Oil Analysis Of Geranium Sylvaticum Extracted By Hydrodistillation And Microwave Distillation, Nuran Kahri̇man, Gonca Tosun, Hasan Genç, Nuretti̇n Yayli

Turkish Journal of Chemistry

The essential oil of Geranium sylvaticum L. (Geraniaceae) was isolated by hydrodistillation (HD) and microwave distillation (MD). The composition of the volatile oils was characterized by GC-FID and GC-MS. A total of 73 and 70 compounds were identified, constituting over 90.3% and 98.7% of oil composition of G. sylvaticum, respectively. Sesquiterpene hydrocarbons were shown to be the main group of constituents (HD: 31.7% and MD: 39.8%). The major component of the oils of G. sylvaticum was \gamma -muurolene (HD: 10.9% and MD: 19.6%). The comparative study showed that the amount of total volatiles (98.7%) and the major constituent (39.8%) were …


Synthesis And Antimicrobial Activities Of Some New 1,2,4-Triazole Derivatives, Nesli̇han Demi̇rbaş, Ahmet Demi̇rbaş, Hacer Bayrak, Hakan Bektaş, Şengül Alpay Karaoğlu Jan 2010

Synthesis And Antimicrobial Activities Of Some New 1,2,4-Triazole Derivatives, Nesli̇han Demi̇rbaş, Ahmet Demi̇rbaş, Hacer Bayrak, Hakan Bektaş, Şengül Alpay Karaoğlu

Turkish Journal of Chemistry

The synthesis of ethyl [3-(cyanomethyl)-5-alkyl-4H-1,2,4-triazol- 4-yl]carbamates (2a-d) was performed starting from ethyl 2-[ethoxy(4- (aryl)methylene]hydrazinecarboxylates (1a, 1b). The treatment of 2a with thiosemicarbazide afforded ethyl [3-[(5-amino-1,3,4-thiadiazol- 2-yl)methyl]-5-(4-nitrophenyl)-4H-1,2,4-triazol-4-yl]carbamates (3a), whereas compound 2b produced 5-{[4-amino-5-(4-methylphenyl)- 4H-1,2,4-triazol-3-yl]methyl}-1,3,4-thiadiazol-2-amine (3b) in the same reaction conditions. The treatment of tert-butyl 2-[2-(4-chlorophenyl)-1-ethoxyethylidene]hydrazinecarboxylate (5) with malonohydrazide or cyanoacethydrazide gave the corresponding 1,2,4-triazol-ylcarbamate derivatives (6 or 9); then the hydrolysis of these compounds resulted in the formation of 3-{[4-amino-5-(4- chlorobenzyl)-4H-1,2,4-triazol-3-yl]methyl}-5-(4-chlorobenzyl)-4H- 1,2,4-triazol-4-amine (7) and [4-amino-5-(4-chlorobenzyl)-4H- 1,2,4-triazole-3-yl]acetonitrile (10), respectively. The synthesis of the Schiff base derivatives 3-(4-chlorobenzyl)-5-{[5-(4-chloroben- zyl)-4-[(2-hydroxyphenyl-methylene)amino]-4H-1,2,4-triazol-3-yl]methyl} -N-(2-hydroxyphenylmethylene)-4H-1,2,4-triazol-4-amine (8), and (5-(4-chlorobenzyl)-4-{[(2,6-dichlorophenyl)methylene]amino}-4H-1,2,4- triazol-3-yl)acetonitrile (12) was performed from the reaction of compounds 7 …


Synthesis, Structural Determination, And Biological Activity Of New 7-Hydroxy-3-Pyrazolyl-4h-Chromen- 4-Ones And Their O-\Beta-D-Glucosides, Kishor Hatzade, Vijay Taile, Pravin Gaidhane, Vishwas Ingle Jan 2010

Synthesis, Structural Determination, And Biological Activity Of New 7-Hydroxy-3-Pyrazolyl-4h-Chromen- 4-Ones And Their O-\Beta-D-Glucosides, Kishor Hatzade, Vijay Taile, Pravin Gaidhane, Vishwas Ingle

Turkish Journal of Chemistry

A convenient route to synthesize some new medicinally important 7-hydroxy-3-pyrazolyl chromones (3a-i) is described. The interaction of 7-hydroxy-3-formyl chromone (1) with various substituted acetophenones and further cyclization with hydrazine hydrate in an aprotic solvent followed by condensation with 2, 3, 4, 6-tetra-o-acetyl-\alpha-dglucopyranosyl bromide afforded 2, 3, 4, 6-tetra-o-acetyl-\beta-d-glucopyranosyloxy-3-(3-aryl-1H-pyrazol-5- yl)-4H-chromen-4-ones (4a-i). Later deacetylation with anhydrous zinc acetate in methanol gave 7-o-\beta-d-glucopyranosyloxy-3-(3-aryl- 1H-pyrazol-5-yl)-4H-chromen-4-ones (5a-i). These compounds were evaluated for their in vitro antimicrobial and anti-oxidant activity. The structures of these newly synthesized o-glucosides were established by IR, NMR, mass spectra, elemental analysis, and chemical analysis.


Synthesis And Characterisation Of Vanadium(Iii) Complexes Of Biphenylphenols, Neeraj Sharma, Maridula Thakur, S C. Chaudhry Jan 2010

Synthesis And Characterisation Of Vanadium(Iii) Complexes Of Biphenylphenols, Neeraj Sharma, Maridula Thakur, S C. Chaudhry

Turkish Journal of Chemistry

The vanadium(III) complexes of composition [VCl_{3-n}(OAr^{1,2})_n.(THF)_2] (OAr^1 = 2-phenylphenoxo and OAr^2 = 4-phenylphenoxo, THF = tetrahydrofuran; n = 1 /to 3) were prepared by in situ reaction of VCl_3.(THF)_3 with sodium salt of respective phenols in tetrahydrofuran. The complexes were characterised by elemental analysis, molar conductance, FTIR, UV-Vis, and FAB-mass spectral and magnetic studies. The thermal behaviour of some of the complexes was studied by TG-DTA. The dinuclear phenoxy bridged octahedral structures for the complexes were inferred from the spectral and magnetic studies.


Azlactone-Functionalized Polymers As Reactive Templates For Parallel Polymer Synthesis: Synthesis And Screening Of A Small Library Of Cationic Polymers In The Context Of Dna Delivery, Bin Sun, Xianghui Liu, Maren E. Buck, David M. Lynn Jan 2010

Azlactone-Functionalized Polymers As Reactive Templates For Parallel Polymer Synthesis: Synthesis And Screening Of A Small Library Of Cationic Polymers In The Context Of Dna Delivery, Bin Sun, Xianghui Liu, Maren E. Buck, David M. Lynn

Chemistry: Faculty Publications

Azlactone-functionalized polymers are used as reactive templates for the synthesis of a library of amine-functionalized polymers of interest in the context of DNA delivery and other applications.


A Model For Understanding Epilepsy In Peromyscus, Kevin Ryan, Gabor Szalai Jan 2010

A Model For Understanding Epilepsy In Peromyscus, Kevin Ryan, Gabor Szalai

Journal of the South Carolina Academy of Science

No abstract provided.


The Effects Of The Sumter Wastewater Treatment Plant On The Survival And Reproduction Of Ceriodaphnia Dubia In Chronic Toxicity Tests, Erin Worley, Pearl R. Fernandes, S. Michele Harmon, Jeff Steinmetz Jan 2010

The Effects Of The Sumter Wastewater Treatment Plant On The Survival And Reproduction Of Ceriodaphnia Dubia In Chronic Toxicity Tests, Erin Worley, Pearl R. Fernandes, S. Michele Harmon, Jeff Steinmetz

Journal of the South Carolina Academy of Science

No abstract provided.


Associative Learning In Larval Dosophila Melanogaster: The Role Of Heredity In Learning Speed And Persistence Of Leaning Into Adulthood, Jasmin Hicklen, Domonique Jones, Michelle Vieyra Jan 2010

Associative Learning In Larval Dosophila Melanogaster: The Role Of Heredity In Learning Speed And Persistence Of Leaning Into Adulthood, Jasmin Hicklen, Domonique Jones, Michelle Vieyra

Journal of the South Carolina Academy of Science

No abstract provided.


Studies Toward The Total Synthesis Of (±)-Α-Yohimbine By Double Annulation, Raghu Ram Chamala Jan 2010

Studies Toward The Total Synthesis Of (±)-Α-Yohimbine By Double Annulation, Raghu Ram Chamala

University of Kentucky Doctoral Dissertations

The indole alkaloids, a class of natural products, have received much synthetic attention for years due to their diverse structures and interesting biological properties. We are particularly interested in synthesizing some of the yohimbine alkaloids extracted from the bark of a tall evergreen African tree (Corynanthe yohimbe, commonly known as fringe tree). Yohimbine and its stereoisomers have been tempting targets for synthetic organic chemists for more than fifty years. These compounds feature a pentacyclic ring system with two heteroatoms and five stereogenic centers.

Broadly, the fifteen different synthetic approaches that led to the successful completion of yohimbine alkaloids …


15N Solid-State Nmr Detection Of Flavin Perturbation By H-Bonding In Models And Enzyme Active Sites, Dongtao Cui Jan 2010

15N Solid-State Nmr Detection Of Flavin Perturbation By H-Bonding In Models And Enzyme Active Sites, Dongtao Cui

University of Kentucky Doctoral Dissertations

Massey and Hemmerich proposed that the different reactivities displayed by different flavoenzymes could be achieved as a result of dominance of different flavin ring resonance structures in different binding sites. Thus, the FMN cofactor would engage in different reactions when it had different electronic structures. To test this proposal and understand how different protein sites could produce different flavin electronic structures, we are developing solid-state NMR as a means of characterizing the electronic state of the flavin ring, via the 15N chemical shift tensors of the ring N atoms. These provide information on the frontier orbitals. We propose that …


Amino Acid Transport In Thermophiles: Characterization Of An Arginine-Binding Protein In Thermotoga Maritima, Matthew S. Luchansky, Bryan S. Der, Sabato D'Auria, Gabriella Pocsfalvi, Luisa Iozzion, Daniela Marasco, Jonathan D. Dattelbaum Jan 2010

Amino Acid Transport In Thermophiles: Characterization Of An Arginine-Binding Protein In Thermotoga Maritima, Matthew S. Luchansky, Bryan S. Der, Sabato D'Auria, Gabriella Pocsfalvi, Luisa Iozzion, Daniela Marasco, Jonathan D. Dattelbaum

Chemistry Faculty Publications

Members of the periplasmic binding protein superfamily are involved in the selective passage of ligands through bacterial cell membranes. The hyperthermophilic eubacterium Thermotoga maritima was found to encode a highly stable and specific periplasmic arginine-binding protein (TM0593). Following signal sequence removal and overexpression in Escherichia coli, TM0593 was purified by thermoprecipitation and affinity chromatography. The ultra-stable protein with a monomeric molecular weight of 27.7 kDa was found to exist as both a homodimer and homotrimer at appreciable concentrations even under strongly denaturing conditions, with an estimated transition temperature of 116 °C. Its multimeric structure may provide further evidence of …


Amino Acid Transport In Thermophiles: Characterization Of An Arginine-Binding Protein In Thermotoga Maritima. 2. Molecular Organization And Structural Stability, Andrea Scirè, Anna Marabotti, Maria Staiano, Luisa Iozzion, Matthew S. Luchansky, Bryan S. Der, Jonathan D. Dattelbaum, Fabio Tanfani, Sabato D'Auria Jan 2010

Amino Acid Transport In Thermophiles: Characterization Of An Arginine-Binding Protein In Thermotoga Maritima. 2. Molecular Organization And Structural Stability, Andrea Scirè, Anna Marabotti, Maria Staiano, Luisa Iozzion, Matthew S. Luchansky, Bryan S. Der, Jonathan D. Dattelbaum, Fabio Tanfani, Sabato D'Auria

Chemistry Faculty Publications

ABC transport systems provide selective passage of metabolites across cell membranes and typically require the presence of a soluble binding protein with high specificity to a specific ligand. In addition to their primary role in nutrient gathering, the binding proteins associated with bacterial transport systems have been studied for their potential to serve as design scaffolds for the development of fluorescent protein biosensors. In this work, we used Fourier transform infrared spectroscopy and molecular dynamics simulations to investigate the physicochemical properties of a hyperthermophilic binding protein from Thermotoga maritima. We demonstrated preferential binding for the polar amino acid arginine …


Tuning Σ-Holes: Charge Redistribution In The Heavy (Group 14) Analogues Of Simple And Mixed Halomethanes Can Impose Strong Propensities For Halogen Bonding, Kelling J. Donald, Bernard K. Wittmaack, Chad Crigger Jan 2010

Tuning Σ-Holes: Charge Redistribution In The Heavy (Group 14) Analogues Of Simple And Mixed Halomethanes Can Impose Strong Propensities For Halogen Bonding, Kelling J. Donald, Bernard K. Wittmaack, Chad Crigger

Chemistry Faculty Publications

Halogen bonding between halide sites (in substituted organic molecules or inorganic halides) and Lewis bases is a rapidly progressing area of exploration. Investigations of this phenomenon have improved our understanding of weak intermolecular interactions and suggested new possibilities in supramolecular chemistry and crystal engineering. The capacity for halogen bonding is investigated at the MP2(full) level of theory for 100 compounds, including all 80 MH4-nXn systems (M = C, Si, Ge, Sn, and Pb; X = F, Cl, Br, and I). The charge redistribution in these molecules and the (in)stability of the σ-hole at X as …


Synthesis, Characterization, Electrochemistry And Biological Properties Of Schiff Bases And Their Metal Complexes., Zuraini Kadir Jan 2010

Synthesis, Characterization, Electrochemistry And Biological Properties Of Schiff Bases And Their Metal Complexes., Zuraini Kadir

Student Works (2010-2019)

A series of new indole hydrazone Schiff bases and their metal complexes have been synthesized, characterized and evaluated for anti-ulcerogenic activity.The Schiff bases derived from indole-3-acetic acid hydrazide and 2-hydroxyacetophenone and their zinc(II), nickel (II) and copper complexes were synthesized by condensation in ethanol. The IR, 1H and 13C NMR, UV Visible data indicate that the hydrazone ligands are coordinated to zinc metal. Indole hydrazones coordinated to zinc(II), nickel(II) and copper(II) metals as dimer ligands. The IR spectrum of the free ligand indicates that in solid state the ligand remains in the keto form. Recrystallization of ligand and complex 5-methyl-2-hydroxyacetophenone …


The Thermal Characteristic Of Imipenem Encapsulated In Low And High Molecular Weight Of Polyethylene Glycol., Abdul Aziz Ismail Jan 2010

The Thermal Characteristic Of Imipenem Encapsulated In Low And High Molecular Weight Of Polyethylene Glycol., Abdul Aziz Ismail

Student Works (2010-2019)

Microencapsulation technique is widely used in pharmaceutical industries to control the release of a drug. Biodegradable polymer such as Polyethylene glycol (PEG) is frequently used as encapsulation material. This study has tried to produce microencapsulation product of Imipenem antibiotics in Polyethylene Glycol.Commercially available product called Tienam® was used as a major source of Imipenem. We used freeze-drying method to produce the microencapsulation products. The successful of producing of this product is confirmed by the yellowish appearance of the product whereby it shows the colour properties of Tienam® Thermal analysis using Differential Scanning Calorimeter (DSC) was used to characterize pure materials …


Studies Of Antioxidant Activity Of Bioactive Compounds Derived From Ardisia Crispa., Hassan Mahmood Kzar Jindal Jan 2010

Studies Of Antioxidant Activity Of Bioactive Compounds Derived From Ardisia Crispa., Hassan Mahmood Kzar Jindal

Student Works (2010-2019)

In recent times, researches have focused on medicinal plants in order to extract natural and low cost antioxidants that can help protect the human body against oxidative stress, and replace the synthetic additives that might be carcinogenic. In present study, the crude extracts of leaves and fruits from Ardisia crispa were investigated for their chemical constituents and antioxidant activity. Preliminary phytochemical screening of the crude extracts via TLC analysis revealed the presence of several secondary compounds mainly, terpenoids and phenolic compounds in addition to alkaloids and saponins. HPLC analysis showed the possibility of presence of gallic acid in the fruits …


Chemical Constituents Of Aglaia Lanuginose. King, Fadzly Adzhar Kamarulzaman Jan 2010

Chemical Constituents Of Aglaia Lanuginose. King, Fadzly Adzhar Kamarulzaman

Student Works (2010-2019)

Aglaia is a small genus of trees that belong to the family Meliaceae. They are widely distributed in India, Malay Peninsula and throughout Indomalesia. The chemistry of Aglaia has been extensively investigated and most of the researches done on these plants focused on their effect as insecticides, antifeedant, growth inhibitors, cytotoxicity and others. The dichloromethane extract from the bark of Aglaia lanuginose were studied. The chromatographic separation on both of the extracts gave ten compounds. The compounds isolated were identified as eichlerialactone 102, methyl eichlerianate 103, cabraleone 104, ocotillone 105, 4-hydroxycinnamyl acetate 106, cabralealactone 107, eichlerianic acid 108, shoreic acid …


Synthesis, Characterization And Biological Activities Of Some Indole Derivatives And Their Metal Complexes., Mohamed Mustafa Mohamed Ibrahim Jan 2010

Synthesis, Characterization And Biological Activities Of Some Indole Derivatives And Their Metal Complexes., Mohamed Mustafa Mohamed Ibrahim

Student Works (2010-2019)

Tryptamine (1H-indole-3-ethyleneamine) Schiff bases were prepared by the condensation reaction of ethanolic solution of tryptamine with: salicylaldehyde (TS), 5 chlorosalicylaldehyde (TCS), 5-nitrosalicylaldehyde (TNS), 3,5-di-tert-butyl-2-hydroxy benzaldehyde (TTET) and the ketones: 2-hydroxyacetophenone (THAP), 5-methyl-2- hydroxyacetophenone (TMeHAP), 5-methoxy-2 hydroxyacetophenone (TOMeHAP), 5- chloro-2-hydroxyacetophenone (TClHAP) and 5-bromo-2 hydroxyacetophenone (TBrHAP). The ligands were coordinated to Zn(II), Cu(II) and Ni(II) by the reaction of metal acetates with the corresponding ligand in a 1 : 2 metal to ligand ratio. The solid products formed were collected, washed with ethanol and recrystallized from a suitable solvent. All the ligands and complexes prepared have been characterized by spectroscopic methods using …


Optimization Of Solid-Phase Microextraction For The Determination Of Organo-Phosphorus And Organo-Chlorine Pesticide Residues In Natural Water Near Aquaculture Farms., Chan Chun Foong Jan 2010

Optimization Of Solid-Phase Microextraction For The Determination Of Organo-Phosphorus And Organo-Chlorine Pesticide Residues In Natural Water Near Aquaculture Farms., Chan Chun Foong

Student Works (2010-2019)

The global shrimp farming industry had a rapid growth in the 1980s due to the high demand for shrimp. Apart from the destruction of mangroves and wetlands, the intensive operation of shrimp aquaculture deteriorated the water quality in the region. Variety of chemicals and biological products were used to prevent the outbreaks of diseases in the intensively managed shrimp ponds. Pesticides were used as disinfectands to kill unwanted organisms in the pond. SPME-GC-ECD method was developed for the determination of azinphos-ethyl, chlorphyrifos-methyl, diazinon, dichlorvos, endosulfan-I, endosulfan-II, endosulfan sulfate and malathion from water samples of shrimp aquaculture area in Manjung district, …


Synthesis, Characterization And Biological Activities Of Three Indole Schiff Bases And Their Copper And Nickel Complexes., Nazzatush Shimar Jamaludin Jan 2010

Synthesis, Characterization And Biological Activities Of Three Indole Schiff Bases And Their Copper And Nickel Complexes., Nazzatush Shimar Jamaludin

Student Works (2010-2019)

Three derivatives of indole-3-carboxaldehyde with indole-3-acetic hydrazide and their copper(II) and nickel(II) complexes were synthesized. The Schiff base compounds were varied on the substituent where each compound holds a hydrogen, chlorine and bromine atom on the 5th position of indole-3-carboxaldehyde. The structures of the ligands and their complexes were elucidated by various characterization methods. All compounds were screened for their biological effects on neuroprotective screening (in vitro), acute toxicity test (in vivo), ethanol-induced gastric ulcer (anti-ulcer) and glucose tolerance test (antidiabetic). All compounds except bromine-containing compounds were not dose dependent while compounds with bromine displayed significant results, acting as inhibitory …


Chemical Constituents Of Cryptocarya Densiflora., Nurul Nazneem Wan Othman Jan 2010

Chemical Constituents Of Cryptocarya Densiflora., Nurul Nazneem Wan Othman

Student Works (2010-2019)

The extraction of alkaloids from the Malaysian Cryptocarya densiflora has been carried out in this study. The alkaloids were extracted from the bark and leaves of this species using acid base extraction and the crude alkaloids obtained were subjected to extensive chromatographic techniques such as thin layer and column chromatography. The structural elucidation of the purified alkaloids were performed with the aid of spectroscopic methods i.e. 1H NMR, 13C NMR, 2D NMR, IR, UV and LCMS. Investigation of the alkaloidal content from the bark of Cryptocarya densiflora afforded six alkaloids and their structures were elucidated as laurotetanine 63, isocaryachine 64, …


Sulfur K-Edge Photo-Fragmentation Of Ethylene Sulfide, Wayne C. Stolte, Gunnar Ohrwall Jan 2010

Sulfur K-Edge Photo-Fragmentation Of Ethylene Sulfide, Wayne C. Stolte, Gunnar Ohrwall

Chemistry and Biochemistry Faculty Research

We have investigated the photofragmentation properties of the three-membered ring heterocyclic molecule ethylene sulfide or thiirane, C2H4S, by time-of-flight mass spectroscopy. Positive ions have been collected as a function of photon energy around the S K ionization threshold. Branching ratios were derived for all detected ions, which are informative of the decay dynamics and photofragmentation patterns of the core-excited species. We present a new assignment of the spectral features around the S K-edge.


Parallel Synthesis Of An Oligomeric Imidazole-4,5-Dicarboxamide Library, Zhigang Xu, John C. Dicesare, Paul W. Baures Jan 2010

Parallel Synthesis Of An Oligomeric Imidazole-4,5-Dicarboxamide Library, Zhigang Xu, John C. Dicesare, Paul W. Baures

Chemistry: Faculty Publications (1990-2023)

A library of oligomeric compounds was synthesized based on the imidazole-4,5-dicarboxylic acid scaffold along with amino acid esters and chiral diamines derived from amino acids. The final compounds incorporate nonpolar amino acids (Leu, Phe, Trp), polar amino acids (Ser, Asp, Arg), and neutral amino acids (Gly, Ala), and were designed to be useful in screening for inhibitors of protein−protein interactions. Many of the protected and deprotected oligomers show evidence of conformational isomers persistent at room temperature in aqueous solution. A total of 317 final oligomers, out of 441 targeted compounds, were obtained in high analytical purity and of sufficient quantity …


Electro-Oxidation Of Some Non-Steroidal Anti-Inflammatory Drugs On An Alumina Nanoparticle-Modified Glassy Carbon Electrode, Mahla Tabeshnia, Hossein Heli, Ali Jabbari, Ali A. Moosavi-Movahedi Jan 2010

Electro-Oxidation Of Some Non-Steroidal Anti-Inflammatory Drugs On An Alumina Nanoparticle-Modified Glassy Carbon Electrode, Mahla Tabeshnia, Hossein Heli, Ali Jabbari, Ali A. Moosavi-Movahedi

Turkish Journal of Chemistry

The electro-oxidation of mefenamic acid, diclofenac, and indomethacin on glassy carbon and alumina nanoparticle-modified glassy carbon electrodes in a phosphate buffer solution at physiological pH was studied. The techniques of cyclic voltammetry, chronoamperometry, impedance spectroscopy, and steady state polarization measurements were applied. The drugs were irreversibly oxidized on bath electrodes via an anodic peak and the process was controlled by diffusion in the bulk of solution. Alumina nanoparticles increased the oxidation current, and lowered the peak and onset potentials. As such, alumina nanoparticles had an electrocatalytic effect, both kinetically and thermodynamically. The kinetic parameters of heterogeneous electron transfer and diffusion …


An Investigation Of Energy Transfer Between Coumarin 35 And Xanthene Derivatives In Liquid Medium, Mahmut Toprak, Mustafa Arik Jan 2010

An Investigation Of Energy Transfer Between Coumarin 35 And Xanthene Derivatives In Liquid Medium, Mahmut Toprak, Mustafa Arik

Turkish Journal of Chemistry

The energy transfer between coumarin 35 (C35) and pyronin compounds, which are xanthene derivatives, i.e. pyronin B (PyB) and pyronin Y (PyY), in methanol was investigated at room temperature by using steady-state absorption, emission, and time-resolved fluorescence spectroscopy. Fluorescence energy transfer rate constants (k_T) and critical radius (R_0) were determined for C35-PyB and C35-PyY molecular pairs in methanol. The obtained values of k_T and R_0 indicated that the dipole-dipole interaction between C35-PyB and C35-PyY molecular pairs accounted for the energy transfer mechanism. The energy transfer efficiency and the distance between the donor and acceptor (r) were also calculated for donor-acceptor …


Silica Supported Polyphosphoric Acid (Ppa-Sio_2): An Efficient And Reusable Heterogeneous Catalyst For The One-Pot Synthesis Of \Alpha -Amino Phosphonates, Malek Taher Maghsoodlou, Sayyed Mostafa Habibi-Khorassani, Reza Heydari, Nourollah Hazeri, Seyed Sajad Sajadikhah, Mohsen Rostamizadeh, Leila Keishams Jan 2010

Silica Supported Polyphosphoric Acid (Ppa-Sio_2): An Efficient And Reusable Heterogeneous Catalyst For The One-Pot Synthesis Of \Alpha -Amino Phosphonates, Malek Taher Maghsoodlou, Sayyed Mostafa Habibi-Khorassani, Reza Heydari, Nourollah Hazeri, Seyed Sajad Sajadikhah, Mohsen Rostamizadeh, Leila Keishams

Turkish Journal of Chemistry

An efficient green protocol is described for the preparation of \alpha -amino phosphonates, employing a one-pot three-component condensation reaction between aldehydes, amines, and trialkyl phosphites in the presence of PPA-SiO_2 under solvent-free conditions at 80 °C. The present procedure offer advantages such as high to excellent yields, short reaction time, inexpensiveness, recovery, and reusability of catalyst.