Synthesis, Spectral Characteristics and Antitumor Activity of Tungstosilicic Polyoxometalate Containing 5-Fluorouracil

A novel polyoxometalate com pound with 5-fluorouracil C4H4FN2O2H3SiW12O40ź12H2O (FSW) was synthesized and its structure was analyzed using IR spectra, X-ray powder diffraction (XRD), 183W NMR and TG. IR spectra and XRD indicate that FSW has a Keggin structure of heteropolyanion with a ring structure of 5-fluorouracil as expected. It was found by the analysis of the 183W NMR spectra that the W atoms of FSW remain in the same chemical environment. The results of TG show that the compound has two weight-losing steps with certain degree of thermal stability. The present study uses 5-fluorouracil as the positive control group in the cytotoxicity tests of FSW on human renal embryonic cell HEK293 and the antitumor activity tests in cervical cancer cell Hela using the methyl thiazolyl tetrazolium method. The results obtained show that the therapeutic index of the new polyoxometalate compound is 0.75, higher than that of 5-fluoro-uracil.