correlation of these results with known reactions of certain aromatic amine derivatives with nucleosides and nucleic acids , and with molecular orbital calculations , suggests that the effect of class a is produced by small aromatic groups attached to extranuclear heteroatoms in dna bases , the effect of class b is caused by large aromatic groups attached to extranuclear heteroatoms or by arylamines attached to c-8 of guanine , while the effect of class c is caused by arylamides attached to c-8 of guanine , probably rotating into the helix , as proposed by others .
C0028606
nucleic acids
C0012854
dna