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Conformational Analogs of Some Phytoactive Compounds

Description: In an effort to determine if there is a specific conformational structure which is most effective at the appropriate active physiological site, the synthesis of a group of sterically restricted analogs was undertaken. A portion of the polymethylene carbon skeleton of glutaric acid was replaced by selected aromatic carbons in benzenedicarboxylic acids to produce a series of ridged conformers, and the relative plant growth regulating properties of these derivatives were determined.
Date: August 1973
Creator: Skelton, Wm. Paul
Partner: UNT Libraries
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Syntheses of Antimetabolites

Description: In these studies several different types of antimetabolites were synthesized, and their biological effects were examined in various assay systems. More extensive investigations were done in microbial systems in which many of the compounds proved to be inhibitory to growth, and attempts were made to determine the mode of biochemical action by adding supplements of the appropriate natural metabolite.
Date: January 1970
Creator: Clifton, George Gil
Partner: UNT Libraries
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Sites of Reactivity During Ligand-Exchange Reactions in Octahedral Group VIB Metal Carbonyls

Description: The site of initial metal-carbonyl bond-breaking during ligand-exchange reactions in a series of octahedral metal carbonyls of the type (L2)M(CO)4 (M = Cr, Mo, W; L2 = diphos, phen, dipy) has been determined employing infrared spectroscopy and Fourier transform nuclear magnetic resonance spectroscopy. The results of this study reveal, for all metal carbonyl complexes of the type mentioned above, that loss of CO occurs exclusively at an axial position (cis to the bidentate ligand, I^)• The dynam… more
Date: December 1979
Creator: Asali, Khalil Jamil
Partner: UNT Libraries
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Kinetics and Mechanism of Reactions of Disubstituted Octahedral Metal Carbonyls with Phosphorus Donor Ligands and Germanium Tetraiodide

Description: The kinetics and mechanism of the reactions of (tmpa)W-(CO)^ and (tmen)W(CO)^ (tmpa = N,N,N',N'-tetramethy1-1,3-diaminopropane and tmen = N,N,N1,N1-tetramethylethylenediamine) with four phosphorus donor ligands (triisopropyl phosphite, triphenyl phosphite, triphenylphosphine and "constrained phosphite", 4-methyl-2,6,7-trioxa-l-phosphabicylo[2.2.2]octane) in xylene have been investigated in detail. These reactions were found to take place by the ring-opening of the bidentate ligand in a reversib… more
Date: August 1976
Creator: Moradi-Araghi, Ahmad
Partner: UNT Libraries
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Studies of the Mechanisms of Reactions of Binary Metal Carbonyls

Description: A kinetic study of the reactions of Group VI-B hexacarbonyls with primary amine and halide ligands was undertaken in order to determine the possible mechanisms of these reactions. As well as the expected dissociative pathway, the reactions with the primary amines were seen to proceed by a concurrent pathway which was dependent upon the ligand concentration. Since nitrogen donor ligands are expected to be poor donor ligands, the mechanism proposed was a "dissociative interchange" mechanism which… more
Date: May 1977
Creator: Pardue, Jerry E.
Partner: UNT Libraries
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Stereochemical Elucidation Of The Tetrahydro [2.2]paracyclophane System

Description: The purpose of this investigation is to study the Birch reduction products of [2.2lparacyclophane and of [2.2]paracyclophane- 2-carboxylic acid. The tetrahydro Birch reduction product of [2.2]paracyclophane is shown to be dl stereoisomer, with the olefins of the upper deck only partially overlapping with the olefins of the lower deck. This stereochemical elucidation is accomplished by means of a complete proton nmr analysis of the tetraepoxide derivative. A proposed mechanism supported by VB (v… more
Date: August 1975
Creator: Song, Ban-Huat
Partner: UNT Libraries
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Regulation of Pyridine Nucleotide Metabolism in Saccharomyces cerevisiae

Description: The levels of total nicotinamide adenine dinucleotide (NAD) and nicotinamide adenine dinucleotide phosphate (NADP), and their redox states were determined as the function of growth in S. cerevisiae. Cells growing in a medium containing 0.8% glucose exhibit two phases of exponential growth, utilizing glucose and ethanol, respectively. The NAD pool is 50% reduced during both stages of growth while the NADP pool is 67% reduced in glucose growth and 48% reduced in ethanol growth. The NAD/NADP ratio… more
Date: May 1976
Creator: Ting, Haung-yu
Partner: UNT Libraries
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Spectroscopic Investigation of Some Allyl Alkali Metal Compounds

Description: To gain better understanding of the nature of the carbonmetal bonding in 3-neopentylallyl alkali metal (5,5-dimethyl- 2-hexenyl alkali metal) systems, an investigation is extended to 3-neopentylallylpotassium. In addition, pertinent data on the 3-neopentylallyl systems are re-examined in an attempt to understand the trends in the bonding habits, as affected by the solvent, the cation and the temperature.
Date: May 1976
Creator: Moore, Michael L.
Partner: UNT Libraries
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Properties of Molecular Rydberg States

Description: Many of the bands in the vapor-phase far-ultraviolet absorption spectra of simple molecules can often be fit to mathematical progressions referred to as molecular Rydberg series. The name Rydberg arises from the similarity between the Rydberg formula for the atomic hydrogen spectrum and the formulae for the progressions found in molecular spectra. The theories of molecular Rydberg transitions and states are discussed in terms of the inferences that have been made in the past from the available … more
Date: December 1974
Creator: Scott, John Delmoth
Partner: UNT Libraries
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Synthesis and Study of Metabolic Antagonists

Description: The central nature of nicotinamide in metabolic processes as a part of the NAD and NADP coenzyme systems prompted the synthesis of a series of N-nicotinyl- and N-isonicotinyl-N'- (substituted)ureas as potential metabolite antagonists of the vitamin. The compounds which were synthesized may be represented by the following general structure, where R = hydrogen, methyl, ethyl, n-propyl, isopropyl, n-butyl, t-butyl, n-hexyl, cyclohexyl, phenyl and a-naphthyl. The observed toxicity of the N-nicotin… more
Date: August 1973
Creator: Masingale, Robert Edesta
Partner: UNT Libraries
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The Determination of Organic-Bound Chlorine Levels in Municipal Wastewaters After Treatment with Heavy Chlorine Doses

Description: The development of an analytical method for the determination of total organic-bound chlorine (TOCl) produced during the chlorination of municipal wastewater effluents is presented. Sewage effluent from the Denton, Texas municipal treatment plant was chlorinated at high chlorine doses (1000 - 4000 ppm), as well as typical treatment levels. Chlororganics present in the wastewater, before and after chlorination, were concentrated by adsorption on Amberlite XAD-2 macroreticular resin, followed by … more
Date: May 1976
Creator: Smith, Garmon B.
Partner: UNT Libraries
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The Chlorination of Amino Acid in Municipal Waste Effluents

Description: In model reaction systems to test amino acids in chlorinated waste effluents, several amino acids were chlorinated at high chlorine doses. (2000-4000 mg/1). Amino acids present in municipal waste effluents before and after chlorination were concentrated and purified using cation exchange and Chelex resins. After concentration and cleanup of the samples, the amino acids were derivatized by esterification of the acid functional groups and acylation of the amine groups. Identification and quantifi… more
Date: July 1977
Creator: Burleson, Jimmie L.
Partner: UNT Libraries
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Organelle- and Organ-Specific Isozymes of Euglena Gracilis and Catfish

Description: Two distinct compartmentalized isozymes of aldolase and triosephosphate isomerase were examined in the photoautotrophically and heterotrophically grown green alga Euglena gracilis. A comparison of the chemical and physical properties of the isozymes was carried out. Isozymes of phosphoglucose isomerase were isolated in homogeneous form from liver and muscle tissue of the fresh water catfish. The two organ-specific isozymes were essentially identical with respect to their molecular weights but e… more
Date: December 1974
Creator: Mo, Yeh-Chun
Partner: UNT Libraries
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Magnetic Properties of Oxovanadium(IV) Complexes of Substituted N-(Hydroxylalkyl) Salicylideneimines

Description: A series of oxovanadium(IV) complexes of Schiff bases derived from substituted salicylaldehyde and aminoalcohols has been prepared and characterized. The Schiff bases coordinate through 0, N, and 0 as tridentate bivalent ligands. The primary purpose of the investigation is to describe the structure and bonding in these complexes. The subnormal magnetic properties of the complexes provide much information about both the structure and the bonding in the complexes.
Date: May 1972
Creator: Carey, Elbert Franklin
Partner: UNT Libraries
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Oxovanadium(IV) Complexes of Substituted N-(2-Thiophenyl)Salicylideneimine

Description: In an effort to study the spectral, magnetic, and stereochemical properties of vanadyl complexes, both a new series of vanadyl complexes derived from type (VII) ligands with subnormal magnetic moment and from type (VIII) ligands with normal magnetic moment are synthesized and characterized.
Date: June 1970
Creator: Lee, Cheng Chang
Partner: UNT Libraries
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ESR Studies of Group IV Substituted Anilines

Description: The purpose of the investigation described herein was to investigate the degree of delocalization of the unpaired electron in ion radicals formed in the oxidation process of compounds with aromatic rings connected by means of various groups and atoms not entering the ring; then, to establish the relationship of coupling constants in radical cations with substituent σ values. The parent cation radical, in which the co-planar ion was derived from N,N-dimethylaniline, was selected in order to maxi… more
Date: June 1970
Creator: Wong, Pui-Suen
Partner: UNT Libraries
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Synthesis of 1-Amino-2-Hydroxycyclopentanecarboxylic Acid

Description: This investigation involved the synthesis of 1-amino-2-hydroxycyclopentanecarboxylic acid, a potential structural analog of the natural amino acids, serine and threonine. The title compound also includes the structural features present in an established antitumor agent, cycloleucine.
Date: December 1970
Creator: Huddle, John David
Partner: UNT Libraries
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Biological Inhibitors

Description: Four isosteric series of plant growth-regulating compounds were prepared. Using an Avena sativa coleptile assay system, derivatives in series I and IV inhibited segment elongation to a greater degree than did comparable derivatives in series II and III.
Date: December 1971
Creator: Sargent, Dale Roger
Partner: UNT Libraries
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High Temperature Enthalpies of the Lead Halides: Enthalpies and Entropies of Fusion

Description: The objectives of this investigation were: 1. To establish calorimetrically the transition temperature for the orthorhombic to cubic transition exhibited by PbF₂ and to determine the enthalpy of this transition. 2. To determine if the solid-solid phase transitions claimed in the literature for PbCl₂, PbF₂, PbBr₂, and PbI₂ were of thermodynamic importance, and if so, to determine the enthalpies of transition. 3. To determine if the discontinuous thermal expansions reported by Hsu for the lead ha… more
Date: June 1970
Creator: Linsey, Clarence W.
Partner: UNT Libraries
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Ketene Carbodiimide Cycloadditions

Description: It was proposed to study the cycloaddition of ketenes and carbodiimides in some detail. The first objective was to investigate the general applicability of the reaction as a tool for the synthetic organic chemist in the preparation of a new class of substituted β-lactams; i.e., imino-β-lactams. It was proposed for this part of the research problem to look for the intermediate, either directly or indirectly, by trapping experiments. It was further proposed to study substituent effects in the ket… more
Date: August 1970
Creator: Dorsey, Edwin Darrell
Partner: UNT Libraries
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