Two new scorpionates vanadium haloperoxidases model complexes: Synthesis and structure of VO(O2)(pzH)(HB(pz)3) and VO(O2)(pzH)(B(pz)4) (pzHÂ =Â pyrazole(C3H4N2))

Using vanadate, poly(1H-pyrazol-1-yl)borate and pyrazole as starting materials, two new neutral peroxovanadium(V) complexes with poly(1H-pyrazol-1-yl)borate, VO(O2)(pzH)(HB(pz)3)(1) and VO(O2)(pzH)(B(pz)4)(2), were synthesized successfully. Both complexes were characterized by elemental analysis, IR, UV-vis and NMR spectra. And the structure of complex 1 was determined by X-ray diffraction, which is somewhat relevant for haloperoxidase enzymes. Cytotoxic effects also are discussed on 3T3 cell proliferation. In the concentration range (0.1-100 μmol), both complexes have an inhibiting cellular proliferation effect. When the cells cultivated with the complexes at high dose, the toxicity effect of both complexes is more and more predominant.