MOLECULAR MECHANICS AND DYNAMICS STUDY OF DNA-FUROCOUMARINS COMPLEXES- EFFECT OF METHYLATION OF THE ANGULAR DERIVATIVES ON THE INTERCALATION GEOMETRY

Results of molecular mechanics calculations on intercalation complexes between DNA and angelicin derivatives: angelicin, 4'-methylangelicin, 5'-methylangelicin, 4,4'-dimethylangelicin, 4,5'-dimethylangelicin, 4 ,6,4'-trimethylangelicin and 4,6,5'-trimethylangelicin, are presented. The correlation between the presence of methyl groups and an increase in DNA photobinding affinity is discussed on the basis of the molecul ar structures. The influence of the orientation of the angelicins with in the intercalation cavity is also discussed. Finally, the consequenc es of the dynamical behaviour of angelicin in the intercalation site a re studied.