Thesis (Ph. D.)-- State University of New York at Binghamton, Department of Chemistry, 2009.

This dissertation describes the synthesis of novel, small molecule building blocks and the phenomena that are revealed when they are studied in unusual environments. Chapter 1 is divided into two sections, serving as introductions for chapters 2-3 and 4-5 respectively. The first section introduces the scanning tunneling microscope break junction (STM-BJ) as a new environment for reaction chemistry. Chapter 2 describes a truly single molecule reaction in which azobenzenes are formed in the STM-BJ one molecule at a time. Chapter 3 describes an electrostatically driven Ullmann coupling reaction of biphenyl iodides in the STM-BJ. In contrast to the reaction described in chapter 2, this reaction occurs throughout the solution in the presence of an electric field that surrounds the nanoelectrodes. The second half of chapter 1 provides a primer on the photoisomerization of azobenzenes, a class of small molecule dyes whose unique photochromic profile and switchable properties have been exploited across a wide range of fields. Chapter 4 introduces azobenzenes as photoswitchable ligands on superatomic clusters. Chapter 5 details the phenomenon and mechanism of white light driven rolling of Cu(I) isocyanoazobenzene crystals. Finally, chapter 6 is a self-contained research project. It details an organocatalytic O₂-coupled oxidation platform that capitalizes on the capacity of hydrazines to undergo rapid autoxidation to diazenes.

In the investigation the effects of excess maleic anhydride, hydrazine hydrate-solvent reagent addition time, volume of reaction mass after concentration by heating at 100 °C, mixing of reactants, and the solvent selected were studied for the heterogeneous reaction of maleic anhydride and hydrazine hydrate. A reaction time of 12 minutes was employed with the ratio of solvent to reactants held constant at 75 weight per cent throughout the tests. Solvents employed in the investigation included ethanol, methanol, isopropanol, glacial acetic acid, water, hydrachloric acid, and benzene. Atmospheric drying tests at 25 to 88 °C were employed on hydrazide slurries of free moisture content from 1.258 to 1.515 pounds of water per pound of hydrazide. Centrifuge tests at 2000 to 4700 revolutions per minute and a rotary filtration test under a 10 inch vacuum were employed on 13 weight per cent hydrazide slurries. Hydrazide filtrate evaporation tests at 100 °C were performed on samples of 18 to 1715 milliliters to determine the approximate hydrazide content in the slurries. Field applications of 0.10 to 0.22 weight per cent hydrazide solutions in water were made on "wild" varieties of briers, bermuda grass, johnson grass, milkweed, red pine, ragweed, and honey locust in the Blacksburg, Virginia, area from May to August, 1956. The yield of maleic acid hydrazide was increased from 42.6 to 67.0 per cent when the maleic anhydride excess was increased to 20 per cent in the reaction. The optimum addition time for the ethanol-hydrazine hydrate reagent to the maleic anhydride was found to be 3.8 seconds, while the optimum volume of reaction mass after concentration by beating at 100 °C was 10 to 15 milliliters for the non-agitated reactions. Agitation of the reaction mass and the solvent chosen were determined to increase the yield of the hydrazide. The optimum drying temperature and time for the drying of the hydrazide slurries were determined to be 88 °C and 75 minutes, respectively. Rotary vacuum filtration of the hydrazide slurries was determined to produce a cake free moisture of 1.33 pounds of water per pound of hydrazide as compared with 1.38 for the centrifuge test at 4700 revolutions per minute. The hydrazide content of the filtrate samples was determined to be approximately 10 to 15 per cent. Field applications on "wild" plots indicated that 40 to 80 per cent control of briers, bermuda grass, ragweed, johnson grass, and red pine could be achieved from one application of 0.10 to 0.22 weight per cent hydrazide solutions in early spring. On milkweed and honey locust growth, the spraying solution would not adhere to the leaf. A total fixed plus working capital of $1,151,740 was determined to be necessary to build a plant for the production of 242 tons of 95.5 percent pure maleic acid hydrazide per year. On this basis, a selling price of $3.00 per pound ($0.05 per gallon) would yield a 13.7 percent return as new earnings on total fixed plus working capital. / Ph. D.

published_or_final_version / Medicine / Master / Master of Philosophy

This report mainly discusses the development of the cysteine based PNA (CPNA), which is an analogue of PNAs. Peptide nucleic acids (PNA), a pseudopeptide DNA mimic, was discovered by Nielsen and his coworker in 1991. PNA is proved to sequence-specifically form a very stable duplex with complementary DNA and RNA strands through Watson-Crick base paring, and it is also capable of binding to duplex DNA by helix invasion. These intriguing properties of PNA implicated great potential for medical and biotechnical applications. Therefore, PNA has attracted many scientists in the fields of chemistry, biology, medicine including drug discovery and genetic diagnostics, molecular recognition. Due to its acyclic, achiral and neutral nature of the backbone, PNA has shown problems such as its poor aqueous solubility, poor cell permeability and instability of PNA-DNA duplexes and triplexes. Accordingly, many synthetic approaches have been directed toward developing modified backbones of PNA. Among those PNA analogs, only few examples including lysine-based monomers, guanidine-based peptide nucleic acids (GPNA) and the aminoethylprolyl PNA (aep-PNA) showed noticeable enhancements with regards to the daunting challenges mentioned above. Reported herein is the summary of our research endeavor to develop the CPNA oligomers with the great water-solubility and cell permeability. Chapter one briefly summarizs the background and history of the PNA as the front-runner of the antisense therapeutic agents. Chapter two discusses the novel protocols that enabled synthesis of the various versions of CPNA monomers for both Fmoc and Boc solid phase synthesis strategies. Chapter three includes the experimental procedures for solution phase preparation of the CPNA monomers. Chapter four starts with the introduction of solid phase synthesis strategy. After the brief review, our efforts on solid phase based synthesis of CPNA oligomers are discussed. Detailed procedures for the solid phase synthesis are summarized in Chapter five. Disclosed In the final chapter is a methodology which enables regioselective mono-acylation of hydrazines. Remarkably, this new protocol gives the mono-acylation on the less-reactive nitrogens of the hydrazines. Carbon disulfide takes the key role for this unique transformation. At the end of the dissertaion, selected NMR and Mass spectra are attached.

Pyrazoles have been studied for over a century as an important class of heterocyclic compounds and continue to attract considerable interest due to the broad range of biological activities they possess. The incorporation of the essential structural features of pyrazoles with a ferrocene moiety could provide new derivatives with unexpected and/or enhanced biological activities since several ferrocene derivatives have already been shown to be active against a number of tumors. For this reason, we investigated the synthesis of ferrocenyl-substituted pyrazoles, such as 1-alkyl/aryl-5-ferrocenylpyrazoles, by employing the reaction between (2-formyl-1-chlorovinyl)ferrocene and hydrazine derivatives. Although this reaction is known, it was not studied in much detail and the low yields of ferrocenyl pyrazoles were obtained. Thus, we have reinvestigated this reaction and improved the yields of pyrazoles by optimizing the reaction conditions. (2-Formyl-1-chloro vinyl)ferrocene was first reacted with the excess amount (3 equivalents) of hydrazine derivative at 25 0C in dioxane under argon for 2 hours, and the resulting mixture was then heated at 100 0C for 6 hours in the same solvent. Under our optimized conditions, these reactions afforded 1-alkyl/aryl-5-ferrocenylpyrazole derivatives in moderate to good yields as a single or major product of the reaction. In some cases, 1-alkyl/aryl-3-ferrocenylpyrazole derivatives resulted from these reactions as very minor products.

Dissertation (Ph.D. )--University of South Florida, 2006. / Includes vita. Includes bibliographical references. Also available online.