Physical Sciences and Mathematics Commons^™

Studies In Peptide Synthesis Towards The Lanthionine Analog Of Des-N-Tetramethyl Triostin A, Ganesh Devdas Kini

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Studies have been carried out towards the synthesis of bicyclic octadidepsipeptide lanthionine 4, an analog of des-N-tetramethyl triostin A. Starting with a symmetrical lanthionine unit 5 (R₁, R₃ = Me; R₂, R₄ = t-butyloxycarbonyl), synthesized from the corresponding cystine by contraction with hexaethylphosphorus triamide, linear octadidepsipeptides 29 and 32 were synthesized.

Attempted cyclizations of 29 and 32 to the bicyclic octapeptide were unsuccessful.

The failure of the symmetrical approach to 4 prompted the synthesis of an unsymmetrical lanthionine unit with appropriate compatible protecting groups. Attempts to synthesize unsymmetrical lanthionines by nucleophilic displacement on …

Cell-Mediated Immunity Of The Dog Lung And Effects Of Inhaled 239puo2 Or Pulmonary Tumors, Jennifer Baker Galvin

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Cell-mediated immunity (CMI) in the lung has not been well characterized due to the lack of applicable tests. A major objective was to define pulmonary CMI serially in immunized and control lung lobes using the leukocyte procoagulant (LPCA) assay in young adult dogs. This was compared to a standard, but less reproducible CMI assay, macrophage migration inhibition facet (MIF). The CMI response, as measured by the LPCA assay, peaked in the blood 7 days after lung immunization. The pulmonary CMI response measured with cells obtained by bronchial lavage from the immunized and control lung lobes peaked at 9 to 12 …

Cow Brain Glutaminase: Purification And Influence Of Phosphate And Borate Ions On Its Activity And Molecular Weight, Mahnaz Badamchian

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

An efficient and simple purification procedure for cow brain glutaminase (L- glutamine amidohydrolase, EC 3.5.1.2) is described. The main steps consisted of acetone extraction and French press treatment in the presence of phosphate ions, precipitation of nucleic acids and lipids by 0.08 % protamine·S04 and high speed centrifugation (300,000xg), ammonium sulfate fractionation, and gel filtration on Sepharose 4B first as the low molecular weight and then as the aggregated form. The yield was 22% and the final preparation had a specific activity of 142 μmoles/min/mg. The purification was more than 8000-fold over crude brain homogenate. The enzyme showed one strong …

Photochemical Energy Storage (Photosensitized Isomerization Of Norbornadiene To Quadricyclane By Copper(I) Complexes), Dennis J. Fife

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

This research has focused on the sensitized photoisomerization step of a solar energy storage system based on the interconversion of norbornadiene (NBD) and quadricyclane (Q). Sensitizers studied in the photoisomerization were arylphosphine complexes of copper(I) halides [(Ph₃P)₃CuX, (MePh₂P)₃CuX, (DIPHOS)CuCl; X = Cl, Br, I and DIPHOS = Ph₂P(CH₂)₂PPh₂]. The lowest electronic excited state of the complexes can be an effective triplet energy sensitizer as evidenced by a maximum quantum yield of 1.0 with (MePh₂P)₃CuX. The sensitization mechanism of the L …

A Statistical Interpretation Of The Rotational Temperature Of No Desorbed For Ru(001), Stephen E. Bialkowski

Stephen E. Bialkowski

A simple model of the rotational state of NO prior to thermal desorption from Ru(001) surface is developed in terms of the rotational heat capacity. The predicted rotational temperature of the desorbed species is consistent with known data on this system. The model is extended to predict translational energy anisotropy in the desorbed NO.

Role Of D Functions In Ab Initio Calculation Of The Equilibrium Structure Of H2s–Hf, Steve Scheiner

Chemistry and Biochemistry Faculty Publications

Full geometry optimizations are performed to determine the equilibrium geometry of the hydrogen‐bonded complex H₂S–HF. The angle between the plane of the H₂S moiety and the H‐bond axis calculated with the 4–31 G basis set is 106° as compared to the experimental value of 91±5°. This quantity is reduced significantly when d orbitals are added to the basis set, yielding an angle within experimental error of 91°. (AIP)