Photochemistry of (Z)-Isovinylneoxanthobilirubic Acid Methyl Ester, a Bilirubin Dipyrrinone Subunit: Femtosecond Transient Absorption and Stimulated Raman Emission Spectroscopy
Language English Country United States Media print-electronic
Document type Journal Article, Research Support, Non-U.S. Gov't
- MeSH
- Bilirubin * chemistry MeSH
- Esters * MeSH
- Photochemistry MeSH
- Phototherapy methods MeSH
- Humans MeSH
- Infant, Newborn MeSH
- Spectrum Analysis, Raman MeSH
- Check Tag
- Humans MeSH
- Infant, Newborn MeSH
- Publication type
- Journal Article MeSH
- Research Support, Non-U.S. Gov't MeSH
- Names of Substances
- Bilirubin * MeSH
- Esters * MeSH
Bilirubin (BR) is an essential metabolite formed by the catabolism of heme. Phototherapy with blue-green light can be applied to reduce high concentrations of BR in blood and is used especially in the neonatal period. In this work, we studied the photochemistry of (Z)-isovinylneoxanthobilirubic acid methyl ester, a dipyrrinone subunit of BR, by steady-state absorption, femtosecond transient absorption, and stimulated Raman spectroscopies. Both the (Z)- and (E)-configurational isomers of isovinylneoxanthobilirubic acid undergo wavelength-dependent and reversible photoisomerization. The isomerization from the excited singlet state is ultrafast (the lifetimes of (Z)- and (E)-isomers were found to be ∼0.9 and 0.1 ps, respectively), and its efficiencies increase with increased photon energy. In addition, we studied sensitized photooxidation of the dipyrrinone subunit by singlet oxygen that leads to the formation of propentdyopents. Biological activities of these compounds, namely, effects on the superoxide production, lipoperoxidation, and tricarboxylic acid cycle metabolism, were also studied. Finally, different photochemical and biological properties of this BR subunit and its structural analogue, (Z)-vinylneoxanthobilirubic acid methyl ester, studied before, are discussed.
Department of Chemistry Faculty of Science Masaryk University Kamenice 5 625 00 Brno Czech Republic
RECETOX Faculty of Science Masaryk University Kamenice 5 625 00 Brno Czech Republic
References provided by Crossref.org
A Platform for the Synthesis of Oxidation Products of Bilirubin