The design, spectrochemistry and toxicity evaluations of two vanadium (IV) complexes: [V(IV)O(2,6-pyridine diacetatato) (H2O)2] (PDOV) and V2(IV)O2(pyrazine-2,3,5,6-tetracarboxylato)(H2O)4] (PYTOV)

Abstract

One major proponent of targeted drug design is the reduction in the risk of toxicities in the host, without compromising the achievement of the desirable therapeutic outcome. In this paper, the synthesis, spectrochemistry and relative oral-toxicity evaluations of a novel bimetallic, vanadyl-centred complex, [V2(IV)O2(pyrazine-2,3,5,6-tetracarboxylato)(H2O)4] (PYTOV) are reported. Using established spectroscopic techniques, comparisons with the previously reported [V(IV)O(pyridine diacetato) (H2O)2] (PDOV), were done and revealed a pH and time-dependent conversion of both complexes to their vanadate analogues. Further to this, at pH 2, PYTOV showed greater stability in relation to PDOV by showing no indication of 51V in the +5 state, from initial NMR studies. Finally, preliminary results from Acute Oral Toxicity (AOT) evaluations, namely Mouse Grimace Scale studies, revealed that rodent study groups, which were orally administered with VOSO4 and PDOV, at a maximum dose of 1000 mg/kg body weight, began showing signs of cytotoxic-related illnesses, while those treated with PYTOV, survived until the scheduled sacrifice with no signs of stress.