Synthesis, anticancer activity and DNA-binding properties of novel 4-pyrazolyl-1,8-naphthalimide derivatives.

A novel series of 4-pyrazolyl-1,8-naphthalimide derivatives have been designed and facilely synthesized. For anticancer activity in vitro, most of the compounds were found to be more toxic against human mammary cancer cells (MCF-7) than human cervical carcinoma cells (Hela) and human lung cancer cells (A549). Compounds 4i, 4h, 4b and 4a showed improved cytotoxic activity against MCF-7 cells over amonafide, in particular compounds 4i and 4h, the IC50 values of which against cell lines of MCF-7 were 0.51 μM and 0.79 μM, respectively. The DNA-binding properties of 4i were investigated by UV-vis, fluorescence, and Circular Dichroism (CD) spectroscopies and thermal denaturation. The results indicated that compound 4i as the DNA-intercalating agent exhibited middle binding affinity with CT-DNA.