Synthesis and anticancer activity of cyclotriphosphazenes functionalized with 4-methyl-7-hydroxycoumarin

As an important branch of heterocyclic compounds, coumarin and its derivatives with diverse potential biological activities have attracted wide attention and have been applied in medical-related fields. In this article, three cyclotriphosphazene derivatives bearing 4-methyl-7-hydroxycoumarin moieties with the numbers of 2, 4, and 6 were synthesized and characterized and their antitumor activities were investigated. All the new compounds were found to display antitumor activity in vitro against breast cancer cell lines (MCF-7 and 4T1 cells) with the IC50 values in the range of 108.72-188.44 mu M and 75.93-154.91 mu M, respectively. In contrast, the coumarin monomer displayed the values of 4140 mu M and 1640 mu M (IC50). Our results suggested that the antitumor activity was significantly enhanced when coumarin was introduced onto the surface of cyclotriphosphazenes, thereby providing potent candidate molecules for pharmaceutical applications.