Fig. 5. UV absorption spectra of DNA with different concentrations of compound 7a (pH = 7.4, T = 303 K). Inset: comparison of absorption at 260 nm between the 7a–DNA complex and the sum values of free DNA and free compound 7a. c(DNA) = 5.20 × 10–5 mol L–1, and c(compound 7a) = 0–2.0 × 10–5 mol L–1 for curves a–i, respectively, at 0.25 × 10–5 mol L–1 increments.
