Cytotoxicity, anticancer, and antioxidant properties of mono and bis-naphthalimido β-lactam conjugates

Article abstract of DOI:10.1007/s00044-020-02552-1

This article reports the diastereoselective synthesis of some novel naphthalimido and bis-naphthalimido β-lactam derivatives and a preliminary evaluation of their anticancer properties. The reactions were completely diastereoselective, leading exclusively to the formation of cis-β-lactams 11a–l and trans-bis-β-lactams 16a–g. All of these compounds were obtained in good to excellent yields and their structures were established based on IR, ¹H NMR, ¹³C NMR spectral data, and elemental analysis. Each of the β-lactams was screened for antioxidant and anticancer activities. Our results showed that all the compounds lacked cytotoxicity against HepG2 cells, whereas 16a and 16b exhibited excellent anticancer activity with IC₅₀ values below 191.57 μM on MCF-7 cell line and also, bis-β-lactams 16a–g showed excellent antitumor activity against the TC-1 cell line. Antioxidant experiments of 16a–d by the diphenylpicrylhydrazyl (DPPH) assay showed IC₅₀ values ranging from 7 to 32.3 μg/ml. Interaction of 16a, 16b, 16d–g with calf-thymus DNA (CT-DNA) was also supported by absorption titration studies. The compounds exhibit good binding propensity to CT-DNA and the DNA binding affinity (K_b) of the compounds varies as 16a; 16b; 16e; 16g > 16d; 16f. Interaction of 16d with CT-DNA was also investigated by fluorescence spectroscopy. The results support an intercalative interaction of 16d and 16f and non-intercalation mechanism for 16a, 16b, 16e, and 16g.