Relationship of the Molecular Size and Charge Density of Polyoxometalates to Their anti-gp120-CD4-binding Activity

The ability of several classes of polyoxometalates to inhibit the interaction between HIV-1 gp120 and CD4 was assessed. No clear relationship was found between binding inhibition and the negative charge density on the anion portion of the polyoxometalate. However, a weak correlation was found with molecular size. There was a molecular weight threshold of 3800 g mol- 1 above which no significant increase in potency was gained; the binding inhibition was nearly quantitative above this molecular weight.