Synthesis and biological activity of novel metal complexes of 2-acetylpyridine thiosemicarbazones.

2-Acetylpyridine-(2-methylthiosemicarbazone), 2-acetylpyridine-(4-methylthiosemicarbazone), 2-acetylpyridine-(4-phenylthiosemicarbazone) and some of their metal complexes of the platinum group have been synthesized, characterized by chemical and spectral methods and studied for their antibacterial, antifungal and amoebicidal activity in vitro. They were studied also for their antimalarial activity and for toxicity in vivo. The platinum metal chelates exhibited significant activity against a wide spectrum of microorganisms at different concentrations. The Ru (III) chelates derived from 2-acetylpyridine-(4-methylthiosemicarbazone) seem to be the most efficient inhibitors. Evaluation of the antimalarial activity of the complexes in mice infected with Plasmodium berghei indicated that cures were attainable at dose levels of 20-160 mg/kg.