Premium
The Radical Cationic Repair Pathway of Cyclobutane Pyrimidine Dimer: The Effect of Sugar‐Phosphate Backbone
Author(s) -
Ebrahimi Ali,
HabibiKhorassani Mostafa,
Shahraki Asiyeh
Publication year - 2012
Publication title -
photochemistry and photobiology
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.818
H-Index - 131
eISSN - 1751-1097
pISSN - 0031-8655
DOI - 10.1111/j.1751-1097.2012.01206.x
Subject(s) - chemistry , cationic polymerization , dimer , lone pair , phosphate , cyclobutane , pyrimidine dimer , sugar phosphates , hydrogen bond , bond cleavage , cleavage (geology) , photochemistry , sugar , stereochemistry , dna , organic chemistry , ring (chemistry) , molecule , biochemistry , dna damage , catalysis , geotechnical engineering , fracture (geology) , engineering
Radical cationic repair process of cis – syn thymine dimer has been investigated when (1) sugar‐phosphate backbones were substituted by hydrogen atoms, (2) phosphate group was substituted by two hydrogen atoms each on a sugar ring and (3) sugar‐phosphate backbone was taken into account. The effect of the interactions between N1 and N1′ lone pairs and the C6‐C6′ antibonding orbital are the most important evidences for the cleavage of the C6‐C6′ bond in the first step of radical cationic repair mechanism in the absence of the sugar‐phosphate backbone. The impact of the N1 and N1′ lone pairs on the C6‐C6′ bond cleavage decreases and the energy barrier of the cleavage of that bond significantly increases in the presence of the deoxynucleoside sugars and the sugar‐phosphate backbone.