Experiments show that the natural products phenyl propanoid glycosides (PPGs) extracted from the plant Pedicularis spicata are capable of repairing DNA damaged by oxygen radicals. Based on kinetic measurements and experiments on tumor cells, a theoretical study of the interaction between PPG molecule Cistanoside C and telomeric DNA fragment has been carried out. The docking calculations performed using JUMNA software showed that the Cistanoside C could be docked into the minor groove of telomeric DNA and form complexes with the geometry suitable for an electron transfer between guanine radical and the ligand. Such complexes can be formed without major distortions of DNA structure and are further stabilized by the interaction with the saccharide side-groups.

Experiments show that the natural substances phenylpropanoid glycosides (PPGs) extracted from pelicularis spicata are capable of repairing DNA damaged by oxygen radicals. Based on kinetic measurements and experiments on tumor cells, a theoretical study of the interaction between PPG molecules and isolated DNA bases, as well as a DNA fragment has been performed. An interaction mechanism reported early has been refined. The docking calculations performed using junction minimization of nucleic acids (JUMNA) software showed that the PPG molecules can be docked into the minor groove of DNA and form complexes with the geometry suitable for an electron transfer between guanine radical and the ligand. Such complexes can be formed without major distortions of DNA structure and are further stabilized by the interaction with the rhamnosyl side-groups.

Verbascoside and rutin possess anti-cancer properties and are capable of repairing DNA damaged by oxygen radicals, acting as powerful antioxidants. Based on kinetic measurements and experiments on tumor cells, docking studies of the two ligand molecules with the receptor telomeric DNA fragments have been carried out. The docking calculations performed using JUMNA software showed that the both molecules can be docked into the minor groove of telomeric DNA and form complexes with suitable geometry for electron transfer between guanine radical and ligands. The reaction mechanism via the electron transfer process is further confirmed through energy calculations for transition states using MOPAC 93 program. Complexes can be formed without major distortion of DNA structure and are further stabilized by the interaction of DNA with the saccharide side-groups. By comparing their energies, the difference of activities of the two compounds can be explained.