Reactions With Platinum (ll) Complexes And Selenium-Containing Amino Acids

Department

Chemistry

Authors

Stephanie Robey, Western Kentucky UniversityFollow

Document Type

Thesis

Abstract

We have reacted [Pt(Me₄en)(D₂O)₂]²⁺ [Me₄En=N,N,N’N’-tetramethylethylenediamine] with Selenomethionine (SeMet), Methionine (Met), and Methylselenocysteine (MeSeCys). When MeSeCys was reacted with [Pt(Me₄en)(D₂O)₂]²⁺, we observed both stereoisomers of Se,N chelates, as well as [Pt(Me₄en)(MeSeCys)Cl]⁺ from ­¹­H NMR Spectroscopy; the latter formed due to the presence of Cl^- in the solution. Both isomers of the chelate seemed to form proportionally to one another, not favoring a specific stereoisomer. Eventually the [Pt(Me₄en)(MeSeCys)Cl]⁺ products became Se,N chelates. We incubated SeMet with NaCl for 30 minutes and then mixed with [Pt(Me₄en)(D₂O)₂]²⁺; we saw equal amounts of the [Pt(Me₄en)(SeMet)Cl]⁺ isomers along with a specific stereoisomer of the Se,N chelate forming first (R chirality), then approximately two hours later the (S) chirality formed. Previously, Met and [Pt(Me₄En(D₂O)₂]²⁺ have been studied by prior students and there were no chiralities favored in the reaction. There were S,N chelates formed, but no specific isomer favored over another. We obtained equal amounts of SeMet, Met and [Pt(Me₄en)(D₂O)₂]²⁺ and mixed the solutions together to see which amino acid would platinate first, either SeMet or Met. The NMR spectra we observed showed that SeMet attached first to [Pt(Me₄en)(D₂O)₂]²⁺, with the (R) chelate forming first, then the (S) chelate. Met was slow to react, and we saw both chelates form at approximately equal rates.

Advisor(s) or Committee Chair

Dr. Kevin Williams

Disciplines

Biochemistry | Chemistry | Other Biochemistry, Biophysics, and Structural Biology

Recommended Citation

Robey, Stephanie, "Reactions With Platinum (ll) Complexes And Selenium-Containing Amino Acids" (2011). Mahurin Honors College Capstone Experience/Thesis Projects. Paper 338.
https://digitalcommons.wku.edu/stu_hon_theses/338