PREPARATION AND CHARACTERIZATION OF BIOLOGICALLY-ACTIVE BISMUTH(III) TROPOLONATO COMPLEXES

Two new types of bismuth(III) tropolonato complexes, nitratobis (tropolonato)bismuth(III) (1d) and phenylbis(tropolonato)bismuthin (If), are synthesized and characterized by elemental analysis, H-1-NMR, C-13-NMR, IR spectroscopy, and conductivity measurements. The structures of 1d and aquabis(4,5-benzotropolonato)bismuth(III) nitrate (6b) are confirmed by X-ray structural analyses. Derivatives of tropolone (2a) and their bismuth(III) complexes are synthesized and characterized in the same manner. Eight of these compounds are tested against Helicobacter pylori (H.p.) bacteria, which cause chronic gastritis and peptic ulcus. Most of the bismuth compounds show high in vitro activity against H.p.