Study about quinolone antibacterial agent modifying the Keggin polyoxotungstates

Abstract

Three new quinolone drug molecules modifying Keggin polyoxometalate compounds have been synthesized under hydrothermal conditions and structurally characterized. Single-crystal X-ray diffraction analysis shows that Keggin clusters modified by [Cu₂(Enro)₃H₂O]⁴⁺ subunits result in formation of dimer {[Cu₂(Enro)₃H₂O][SiW₁₂O₄₀]}₂ in 1; in 2, Keggin clusters are modified by two [Cu(Norf)₂]²⁺ subunits in the symmetrical coordinated mode, and then, discrete [Cu₂(Norf)₄][SiW₁₂O₄₀] is obtained; in 3, Keggin clusters are fused together via [Ni(Enro)₂]²⁺ subunits giving the 1D drug-polyoxometalates (POMs) hybrid chain. Antitumor activities in vitro show that 3 exhibits good antitumor activity, while 1 and 2 and their parent SiW₁₂ show no anti-SGC7901 or anti-SMMC7721 activities, indicating that the antitumor activities rest on differences of metal ions, differently affecting electron transfer between quinolone and POMs.

Keywords:

• Polyoxometalate
• Quinolone
• Antitumor activity
• Copper
• Nickel

Acknowledgements

This study is financially supported by the National Natural Science Foundation (Grant No. 21271089), the Scientific and technological innovation team (2012TD010) and Postdoctoral Foundation in Heilongjiang Province.