Spiroiminodihydantoin is a major product in the photooxidation of 2'-deoxyguanosine by the triplet states and oxyl radicals generated from hydroxyacetophenone photolysis and dioxetane thermolysis.
[reaction: see text] Photolysis of hydroxyacetophenone and thermolysis of the corresponding dioxetane afford spiroiminodihydantoin rather than 4,8-dihydro-4-hydroxy-8-oxo-2'-deoxyguanosine (4-HO-8-oxodG) through the oxidation of 2'-deoxyguanosine (dG) by triplet-excited hydroxyacetophenone and the peroxyl radicals derived thereof by alpha cleavage and subsequent oxygen trapping. The structure of the spiroiminodihydantoin is assigned by the SELINQUATE NMR technique, which unequivocally establishes the spirocyclic connectivity.
Adam
Waldemar
W
Institut für Organische Chemie, Universität Würzburg, Am Hubland, D-97074 Würzburg, Germany. adam@chemie.uni-wuerzburg.de
Arnold
Markus A
MA
Grüne
Matthias
M
Nau
Werner M
WM
Pischel
Uwe
U
Saha-Möller
Chantu R
CR
D002851:Chromatography, High Pressure Liquid; D003849:Deoxyguanosine / Q000737:chemistry*; D004578:Electron Spin Resonance Spectroscopy; D005609:Free Radicals; D006151:Guanosine / Q000031:analogs & derivatives* / Q000737:chemistry*; D006358:Hot Temperature; D007202:Indicators and Reagents; D007700:Kinetics; D009682:Magnetic Resonance Spectroscopy; D010084:Oxidation-Reduction; D010782:Photolysis; D013141:Spiro Compounds / Q000737:chemistry*
D005609:Free Radicals; D007202:Indicators and Reagents; D013141:Spiro Compounds; C408822:spiroiminodihydantoin; D006151:Guanosine; D003849:Deoxyguanosine