Antitumor activity and toxicity of peroxo heteroligand vanadates(V) in relation to biochemistry of vanadium

Abstract

A selected set of 14 V(V) complexes was tested for toxicity and antitumor activity against L1210 murine leukemia, to examine the biological properties of peroxoheteroligand vanadates(V) of the formula (NH 4) 4[O{VO(O 2) 2} 2], M 3 I[VO(O 2) 2C 2O 4], and M I[VO(O 2)L], L = malate, citrate, iminodiacetate, nitrilotriacetate, and EDTA. The x-ray structure is known for five of these compounds. A relationship has been found between the chemical composition and the biological activity (antitumor activity-toxicity) of these complexes. Activity in the L1210 system is defined as ⩾25% increase in life span, and this was seen with (NH 4) 4[O{VO(O 2) 2} 2]; M 3[VO(O 2) 2(C 2O 4)]2H 2O, M = K, NH 4; and NH 4[VO(O 2)Malato]H 2O. These observations are important for the biochemistry of vanadium. The special nature of electron transfer within the V(V)-peroxo moiety is proposed to be responsible for this phenomenon. Peroxo heteroligand vanadates(V) therefore represent a model system for studying some biochemical interactions of vanadium in living matter.