Report of Interaction Between Calf Thymus DNA and Pyrimidine-Annulated Spiro-Dihydrofuran

The study of binding interaction between pyrimidine-annulated spiro-dihydrofuran (PSDF) with calf thymus DNA (CTDNA) using UV absorption, fluorescence, circular dichroism (CD), and molecular docking methods. The experimental results revealed that PSDF preferred to bind to the groove of CTDNA with the binding constant (K) of 1.51×102 L/mol at 293 K. Based on the signs and magnitudes of the enthalpy change (ΔH = -33.25 kJ/mol) and entropy change (ΔS= -71.58 J/mol/K) in the binding process it can be concluded that the main interaction forces between PSDF and CTDNA in the binding process were van der Waals force and hydrogen bonding interaction. The results of CD experiments revealed that PSDF did not disturb native conformation of CTDNA and the significant binding of PSDF in PSDF-CTDNA complex was observed from the molecular docking results