Synthesis, characterization and biological activities of nitrophenol-substituted phosphazene dendrimers

Abstract

This study introduces the synthesis and characterization of two novel nitrophenol-substituted phosphazene dendrimers, [N3P3(OC6H5NO2)6] (III) and [N3P3(OC6H5(NO2)2)5O]ˉ.C6H16N+.H2O (IV), derived from hexachlorocyclotriphosphazene (HCCP). The structures of the compounds were determined using elemental analysis, infrared spectroscopy, and X-ray crystallography. The optical properties of the crystals were investigated by photophysical methods. The thermal properties of the compounds were measured by thermogravimetry-differential thermal analysis (TG-DTA). The antibacterial and anticancer properties of the compounds were tested based on the antibacterial tests against Gram-negative (Escherichia coli ATCC 8739 G(-)) and Gram-positive (Staphylococcus aureus ATCC 6538 G(+), Bacillus subtilis 2a ATCC 23,857 G(+)) bacteria, as well as the MTT assay test on K562 leukemia cells (ATCC: CCL-243) and MCF-7 breast cancer cells (ATCC: HTB-22). The presence of six homogeneous 2-nitrophenol substitutions in compound III reduces the fluorescence of the phosphazene ring. The results showed that compound IV has a higher fluorescence intensity and similar toxicity to MCF-7 and HDF cells. The structural differences and the number of nitro groups in the nitrophenol ligands account for these variations. Our results suggest that these cyclophosphazene derivatives have promising properties for biomedical applications and further studies are warranted to explore their mechanisms of action and therapeutic potential.