Investigations of antiproliferative and antioxidant activity of β-lactam morpholino-1,3,5-triazine hybrids

This article reports for the first time the synthesis of some novel β-lactam morpholino-1,3,5-triazine hybrids by a [2+2]-cycloaddition reaction of imines 7a-c, 9a-c and 11 with ketenes derived from substituted acetic acids. The reaction was totally diastereoselective, leading exclusively to the formation of cis-β-lactams 8a-l, 10a-f and 12a-c. The synthesized compounds were tested for activity towards SW1116, MCF-7 and HepG2 cancer cell lines and non-cancerous HEK-293 cell line by MTT assay. None of the compounds exert an observable effect on HepG2, MCF-7 and HEK-293 cells, but compounds 7b, 8f, 8g, 8l, 10c, and 10e exhibited excellent growth inhibitory activity (IC₅₀ < 5 µM) against SW 1116 cells, comparable to that of doxorubicin (IC₅₀ = 6.9 µM). An evaluation of the antioxidant potential of each of the compounds, performed by diphenylpicrylhydrazyl (DPPH) assay, indicated that 7b, 9a, 9b and 9c have strong free radical scavenging activity. UV absorption titration studies reveal that 7b, 8l, 8g and 8f interact strongly with calf-thymus DNA (CT-DNA) in the order of 8l > 7b > 8f > 8g. Collectively, the in vitro capabilities of some of these morpholino-triazine imines and β-lactams suggest possible applications to development of new antioxidants and DNA binding therapeutics.