Life Sciences Commons^™

Synthesis And Characterization Of N-Alkyl-Adenosine-5'-Diphosphates, Han-Ping Huang

Chemistry & Biochemistry Theses & Dissertations

n-Alkylphosphates and adenosine derivatives have been observed to be competitive inhibitors of coenzyme molecules in many NAD⁺ requiring enzymes. In earlier studies, adenosine derivatives such as AMP, ADP and ADP-ribose were found to be coenzyme competitive inhibitors of the Lactate Dehydrogenase catalyzed reaction. However, n-alkylphosphates, to the contrary, + were found to be noncompetitive inhibitors of NAD⁺.

Furthermore, it was observed previously in Dr. Yuan's laboratory that the effect of n-octylphosphate on the LDH catalyzed reaction was changed from noncompetitive to competitive in the presence of low concentration of AMP. Rossmann et al. reported that the binding …

Investigation Of Complex Formation By Oligomers Of Cytosine And Guanosine, Steven Roberts Davis

Chemistry & Biochemistry Theses & Dissertations

Duplex formation between oligo(C:G) _n where n=3 to 4 was shown not to occur under conditions favorable for duplex formation between poly G and poly C. Instead, a stable guano sine self-structure was found to form which a T_m of 50°C for (Gp)₃ and 80°C for (Gp)₄ at strand concentrations of 10^-5M in 1M NaCl. Neither a duplex nor a self-structure formed in the absence of salt.

Oligomers of guanosine and cytosine were obtained by basic hydrolysis and separated according to chain length using DEAE Sephadex column chromatography. Separation of cytosine oligomers with chain lengths …

Synthesis Of Potential Long Acting Calcium Channel Antagonists: A Study Of 1,4-Dihydropyridine Analogs, Thomas E. Christos

Chemistry & Biochemistry Theses & Dissertations

An investigation was undertaken to synthesize and evaluate longer acting analogs to the antihypertensive agent nifedipine. Analogs that are capable of covalent bonding to the nifedipine receptor were considered. These compounds may show increased activity as they will remain at the receptor for a longer period of time.

During the course of this study, previously unreported and unexpected products were encountered and lead to a more intense examination of the Hantzsch synthesis. Of particular interest was the oxazolidine 25 which was a major component of the Hantzsch synthesis when ethanolamine was used instead of ammonium hydroxide. Also isolated during this …

Short-Term Feedback Regulation Of Camp By Accelerated Degradation In Rat Tissues, Tom W. Gettys, Peter F. Blackmore, J. Bruce Redmon, Stephen J. Beebe, Jackie D. Corbin

Bioelectrics Publications

A recent study showed that cAMP analogs lowered cAMP levels in rat hepatocytes. The present work demonstrates that cAMP analogs also lowered cAMP in a rapid, concentration-dependent manner in heart and fat cells. In order to determine if the cAMP-dependent protein kinase mediated this effect, techniques were developed to assay the protein kinase activity ratio in hepatocytes treated with cAMP analogs. The activation of protein kinase and phosphorylase in hepatocytes by 8-pClΦS-cAMP (where 8-pClΦS- indicates 8-parachlorothiophenyl-) was concentration-dependent and occurred in parallel to proportionate decreases in cAMP. More than 20% of the cAMP binding sites on the protein kinase were …