College of Science and Health Theses and Dissertations

Date of Award

Winter 3-19-2016

Degree Type


Degree Name

Master of Science (MS)



First Advisor

Justin Maresh, PhD

Second Advisor

Ruben Parra, PhD

Third Advisor

Catherine Southern, PhD


There is an extensive history of the use of alkaloids for medicinal purposes. Today, development of novel pharmaceutical alkaloids is imperative to developing effective drugs. The Pictet-Spengler reaction of dopamine with 4-hydroxyphenyl-acetaldehyde is the first step in the biosynthesis of thousands of known alkaloids. In this reaction, mechanisms have been proposed to explain the specificity of phosphate catalysis. However, the uniqueness of the phosphate ion in the Pictet-Spengler reaction is not explained. The Pictet-Spengler reaction of dopamine with propanal in phosphate buffer and in maleic acid buffer were evaluated and determined to be comparable. The reaction was found to be dependent on the base concentration in both buffers. When determining the rate limiting step, deuterated dopamine reacted at a slower rate than the natural abundance species and a large kinetic isotope effect was observed. This suggested that deprotonation is the rate-limiting step. In addition, an isomer of tetrahydroisoquinoline was observed, which we call isoTHI.

SLP Collection


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Chemistry Commons