Blocking cyclobutane pyrimidine dimer formation by steric hindrance.
The efficiency of thymine (Thy) and uracil (Ura) to form cyclobutane pyrimidine dimers (CPDs) in solution, upon UV irradiation differs by one order of magnitude. This could to be partially related to the steric hindrance induced by the methyl at C5 in thymine. The aim of the present work is to establish the influence of a bulky moiety at this position on the photoreactivity of pyrimidines. With this purpose, photosensitization with benzophenone and acetone of a 5-tert-butyl uracil derivative () and the equivalent Thy () has been compared. Introduction of the tert-butyl group completely blocks CPD formation. Moreover, the mechanistic insight obtained by laser flash photolysis is in accordance with the observed photoreactivity.
Instituto Universitario Mixto de Tecnología Química (UPV-CSIC), Universitat Politècnica de València, Av. Los Naranjos s/n 46022, Valencia, Spain. mmiranda@qim.upv.es mcuquere@itq.upv.es.
Victoria
V
Vendrell-Criado
Instituto Universitario Mixto de Tecnología Química (UPV-CSIC), Universitat Politècnica de València, Av. Los Naranjos s/n 46022, Valencia, Spain. mmiranda@qim.upv.es mcuquere@itq.upv.es.
Virginie
V
Lhiaubet-Vallet
Division of Molecular Science, Faculty of Science and Technology, Gunma University, Kiryu Gunma 376-8515, Japan.
Minoru
M
Yamaji
Instituto Universitario Mixto de Tecnología Química (UPV-CSIC), Universitat Politècnica de València, Av. Los Naranjos s/n 46022, Valencia, Spain. mmiranda@qim.upv.es mcuquere@itq.upv.es.
M Consuelo
MC
Cuquerella
Instituto Universitario Mixto de Tecnología Química (UPV-CSIC), Universitat Politècnica de València, Av. Los Naranjos s/n 46022, Valencia, Spain. mmiranda@qim.upv.es mcuquere@itq.upv.es.
Miguel A
MA
Miranda
D000096:Acetone / Q000737:chemistry; D001577:Benzophenones / Q000737:chemistry; D003503:Cyclobutanes / Q000737:chemistry*; D019281:Dimerization; D007834:Lasers; D015394:Molecular Structure; D010782:Photolysis; D017319:Photosensitizing Agents / Q000737:chemistry; D011740:Pyrimidine Dimers / Q000138:chemical synthesis / Q000737:chemistry*; D014466:Ultraviolet Rays; D014498:Uracil / Q000031:analogs & derivatives / Q000737:chemistry
D001577:Benzophenones; D003503:Cyclobutanes; D017319:Photosensitizing Agents; D011740:Pyrimidine Dimers; D000096:Acetone; D014498:Uracil; C047723:benzophenone