THE BIOLOGICAL AND MEDICINAL CHEMISTRY OF BISMUTH

Bismuth compounds have been widely used in medicine for more than 200 years, and new bismuth-containing drugs are now being developed. Howev er the biological chemistry of bismuth is poorly understood. We review here methods for the study of bismuth compounds, and use of Bi(III) i n antiulcer, antibacterial, anti-HIV and radiotherapeutic agents is de scribed. The chemistry of Bi(III) carboxylates and amino-carboxylates is dominated by intermolecular interactions which lead to polymeric st ructures. Bi(III) exhibits a highly variable coordination number and c oordination geometry, and alkoxide ligands can induce a strong stereoc hemical ''lone-pair effect''. Bi(III) can bind to both Zn(II) sites (e .g. metallothionein) and Fe(III) sites (e. transferrin) in proteins. F urther work is needed to understand the relationship between the struc tures and dynamics of bismuth compounds and their bioactivity.