Organic Chemistry Commons^™

Effluent Organic Nitrogen (Eon): Bioavailability And Photochemical And Salinity-Mediated Release, Deborah A. Bronk, Quinn N. Roberts, Marta P. Sanderson, Elizabeth A. Canuel, Patrick G. Hatcher, Rajaa Mesfioui, Katherine C. Filippino, Margaret R. Mulholland, Nancy G. Love

Chemistry & Biochemistry Faculty Publications

The goal of this study was to investigate three potential ways that the soluble organic nitrogen (N) fraction of wastewater treatment plant (WWTP) effluents, termed effluent organic N (EON), could contribute to coastal eutrophication - direct biological removal, photochemical release of labile compounds, and salinity-mediated release of ammonium (NH₄+). Effluents from two WWTPs were used in the experiments. For the bioassays, EON was added to water from four salinities (∼0 to 30) collected from the James River (VA) in August 2008, and then concentrations of N and phosphorus compounds were measured periodically over 48 h. Bioassay results, based …

Sequence And Structural Analysis Of The Chitinase Insertion Domain Reveals Two Conserved Motifs Involved In Chitin Binding, Hai Li, Lesley H. Greene

Chemistry & Biochemistry Faculty Publications

Background: Chitinases are prevalent in life and are found in species including archaea, bacteria, fungi, plants, and animals. They break down chitin, which is the second most abundant carbohydrate in nature after cellulose. Hence, they are important for maintaining a balance between carbon and nitrogen trapped as insoluble chitin in biomass. Chitinases are classified into two families, 18 and 19 glycoside hydrolases. In addition to a catalytic domain, which is a triosephosphate isomerase barrel, many family 18 chitinases contain another module, i.e., chitinase insertion domain. While numerous studies focus on the biological role of the catalytic domain in chitinase activity, …

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 …

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

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 …

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

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, …

New Palm Oil Products By Enzymatic Interesterification And Dry Fractionation., Saw Mei Huey

Student Works (2010-2019)

Palm olein is one of the major palm oil products that domestically and industrially used as cooking or frying oil. Palm olein tends to crystallize at low temperature that limits its usage in temperate countries. In spite of various nutritional studies, palm olein is also not well considered as recommended choice due to its higher saturation content. Against these factors, there is a need to reduce its saturation content. In this study, the saturation content in palm olein was reduced through the combination of enzymatic interesterification and dry fractionation. Enzymatic interesterification allows interchanging of acyl groups between and within triacylglycerols …

Synthesis, Characterization And Electrochemical Studies Of Cu(Ii), Fe(Ii), Fe(Iii) And Ni(Ii) Complexes Of Someo-Phenylenediamine Schiff Bases., Abdulaziz Ali Alomari

Student Works (2010-2019)

Four Schiff base ligands, N,N’-1,2-benzene-1,2-diyl-bis(5-chlorosalicylideneimine) (H2L1), N,N’-1,2-benzene-1,2-diyl-bis(4-bromosalicylideneimine) (H2L2), N,N’-1,2- benzene-1,2-diyl-bis(4-hydroxysalicylideneimine) (H2L3), and N,N’-1,2-benzene-1,2-diyl-bis(3-bromo-5-chlorosalicylideneimine) (H2L4) were obtained in good yields from the condensation reaction of o-phenylenediamine with 5-chlorosalicylaldehyde, 5-bromosalicylaldehyde, 4-hydroxysalicylaldehyde and 3-bromo-5-chlorosalicylaldehyde respectively. These Schiff bases formed complexes with copper(II), iron(II) and nickel(II) ions in good yields. The structures of these complexes are mainly square planar, which is confirmed by the crystal structure of nickel(II) complex of bis-N,N’-3-chloro-5-bromosalicylideneamine-,2-diaminobenzene. Attempts to prepare the corresponding iron(III) complexes were unsuccessful. The ligands were characterized by Fourier transform infrared spectroscopy, elemental analysis, 1H-Nuclear magnetic resonance spectroscopy and UV-vis spectroscopy, while the complexes were characterized by …

Supramolecular Self-Assembly Strategies Involving Water Soluble Calixarenes., Irene Ling

Student Works (2010-2019)

Fundamental investigations of host-guest interactions on the supramolecular self-assembly involving water-soluble p-sulfonatocalix[4]arene, with a series of imidazolium-based cations and pyrrolidinium cation with variable alkyl chain lengths, which featured extensively in ionic liquids have been established. Combinatorial studies incorporating multiple components concerning p-sulfonatocalix[4]arene, imidazolium cations or pyrrolidinium cation, phosphonium cations and lanthanide ions have been developed, which yielded diverse solid state motifs with a common structural characteristic that the imidazolium or pyrrolidinium cation resides in the cavity of the calixarene. Shorter terminal alkyl chain of mono-imidazolium molecules, i.e. n-ethyl and n-butyl imidazoliums are confined in the „molecular capsule‟, being encapsulated by …

1, 2-Bis (Phenylsulfonyl)-1h-Indole As An Acceptor Of Organocuprate Nucleophiles, David C. Qian, Philip E. Alford, Tara L. S. Kishbaugh, Sean T. Jones, Gordon W. Gribble

Dartmouth Scholarship

1,2-Bis(phenylsulfonyl)-1H-indole is a novel example of an electron-deficient indole that undergoes nucleophilic attack at C-3. Though a variety of other organometallic nucleophiles fail to engender nucleophilic substitution, organocuprates produce 3-substituted 2-(phenylsulfonyl)-1H-indoles. These reactions contribute to the growing number of examples of nucleophilic addition to the indole core.

An Improved Synthesis Of A Ring-C Precursor To Cobyric Acid, Hui Wang, Peter A. Jacobi

Dartmouth Scholarship

Alkyne acid 10 was prepared in enantioselective fashion from allylic ester derivative (R)-18 via an E-selective Ireland-Claisen rearrangement followed by Si-assisted elimination of HBr. The present route offers significant advantages in terms of both scalability and overall yield compared to that previously described. Alkyne acid 10 is an attractive ring-C precursor for an ongoing synthesis of cobyric acid.

Synthesis, Characterization And Biological Activity Of Copper (Ii) And Zinc (Ii) Complexes Of Thiosemicarbazones And Their N(4)-Substituted Derivatives Derived From 2,4-Dihydroxybenzaldehyde., Tan Kong Wai

Student Works (2010-2019)

Four thiosemicarbazones ligands (1-4) have been prepared with good yield by refluxing 2,4-dihydroxybenzaldehyde with thiosemicarbazide or N(4)-substituted thiosemicarbazide in ethanol or methanol. From these four ligands, 16 new ternary metal complexes (5-20) with the general formulation of M(B)L have been prepared from the reactions of metal acetates with 2,4-dihydroxybenzaldehyde N(4)-substituted thiosemicarbazone in the presence of N,N-heterocyclic base (M2+ = Zn2+ or Cu2+; B = 2,2'-bipyridine, (bpy); 1,10-phenanthroline, (phen); L2- = doubly deprotonated thiosemicarbazones = 2,4-dihydroxybenzaldehyde thiosemicarbazonato, (HT); 2,4-dihydroxybenzaldehyde 4-methylthiosemicarbazonato, (HM); 2,4-dihydroxybenzaldehyde 4-ethylthiosemicarbazonato, (HE) and 2,4-dihydroxybenzaldehyde 4-phenylthiosemicarbazonato, (HP)) These compounds have been characterized by elemental analyses, IR, UV-Vis, NMR and magnetic …

Synthesis Of Novel Glycosylidene-Based Quinolines, Peter H. Dobbelaar

Seton Hall University Dissertations and Theses (ETDs)

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Microporous Organic Polymers: Synthesis And Post Synthetic Modifications, Phillip Andrew Kerneghan

Theses and Dissertations (Comprehensive)

Microporous solids are an important class of materials that have been studied extensively. Newer to this field are Microporous Organic Polymers (MOPs) which are networks constructed from smaller organic building blocks and exhibit large surface areas, small pore sizes and low densities. It is due to these characteristics that MOPs have attracted attention because of their potential use in applications such as catalysis, chemical separations and gas storage.

In this thesis is described the synthesis of two novel MOPs, the first of which being a network based on benzenediboronic acid and triptycene building blocks linked together by boronate esters. This …

A New Photochemical Method For The Preparation Of Amino Acid-α-Phenylthioesters And Peptide-α-Phenylthioesters, Tyrone Hogenauer

Open Access Theses & Dissertations

We describe the development of a novel resin with a photoreactive N-acylnitroindoline linker that allows for the synthesis of amino acid- (in solution) or peptide-α-thioesters using standard Fmoc/t-Bu standard solid phase peptide synthesis (SPPS). Recent advances have shown that the yields of this thioesterification reaction have dramatically increased due to a simple change in the order of addition of reagents. Upon illumination with UV-light, in the presence of N-hydroxybenzotriazole (HOBt), the amino acid- or peptide-α-OBt ester is generated by direct photo-release from the nitroindoline linker with minimal epimerization, followed by reaction with thiophenol in the dark to produce amino acid-α-phenylthioesters …

Titanium Niobium Nano Porous Materials: New Photocatalysts For Water Decontamination, Maryam Zarei Chaleshtori

Open Access Theses & Dissertations

Water pollution is major environmental problem worldwide. Many common industrial organic compounds that make their way into water systems can be carcinogenic at trace levels and are difficult and costly to remove completely with conventional technologies. Because of this, authorities and researchers are trying to improve current water cleanup techniques.

Heterogeneous photocatalysts that accelerate the photocatalytic destruction of organic contaminants in water are a potentially inexpensive and highly effective way to remove both trace-level and saturated harmful compounds from industrial waste streams and drinking water. Titanium dioxide has the potential to completely mineralize organic compounds in water under ultraviolet light. …

Oxidation Of Dibenzothiophene To Dibenzothiophene Using Metal Nanoparticles Supported On Silica, Karina Castillo

Open Access Theses & Dissertations

Silica and nanoparticles of Pt, Au, and Ag supported on silica were tested for the ability to oxidize dibenzothiophene (DBT) to sulfone. High performance liquid chromatography was used to study the removal of DBT from solution. In addition, X- ray diffraction, infrared spectroscopy and Raman Spectroscopy were used to characterize the product of the oxidation reaction. Further studies involved the use X-ray absorption spectroscopy to characterize the nanoparticle catalysts before and after the oxidation reaction.

To better understand the reaction, silica was synthesized at different pHs using three different acids. The acids used to synthesize the silica were HCl, HNO3, …

Development Of Novel Ahr Antagonists, Hyosung Lee

University of Kentucky Doctoral Dissertations

Aryl hydrocarbon receptor (AHR) is a sensor protein, activated by aromatic chemical species for transcriptionally regulating xenobiotic metabolizing enzymes. AHR is also known to be involved in a variety of pathogenesis such as cancer, diabetes mellitus, cirrhosis, asthma, etc. The AHR signaling induced by xenobiotics has been intensively studied whereas its physiological role in the absence of xenobiotics is poorly understood. Despite a number of ligands of AHR have been reported thus far, further applications are still hampered by the lack of specificity and/or the partially agonistic activity. Thus, a pure AHR antagonist is needed for deciphering the AHR cryptic …

Bismuth(Iii) Bromide In Organic Synthesis. A Catalytic Method For The Allylation Of Tetrahydrofuranyl And Tetrahydropyranyl Ethers, Ram Mohan, Scott Krabbe, Veronica Angeles

Scholarship

A bismuth bromide-catalyzed (10.0 mol %) multicomponent reaction involving the allylation of THF- and THP-ethers, followed by in situ derivatization with acetic anhydride to generate highly functionalized esters has been developed under solvent-free conditions. To the best of our knowledge, this is the first report of a catalytic procedure for the allylation of THF- and THP-ethers to yield ring-opened products.