ACENAPHTHENEQUINONE THIOSEMICARBAZONE AND ITS TRANSITION-METAL COMPLEXES - SYNTHESIS, STRUCTURE, AND BIOLOGICAL-ACTIVITY

The reaction of iron, nickel, copper, and zinc chlorides or acetates w ith acenaphthenequinone thiosemicarbazone, Haqtsc leads to the formati on of novel complexes that have been characterized by spectroscopic st udies (NMR, IR) and biological properties. The crystal structures of t he free ligand Haqtsc 1 and of the compound [Ni(aqtsc)(2)]. DMF 2, hav e also been determined by X-ray methods from diffractometer data. In 1 , the conformation of the two nonequivalent molecules is governed by i ntramolecular hydrogen bonds, while an intermolecular hydrogen bond is responsible for dimer-like groups formation. In 2, the coordination g eometry about nickel is distorted octahedral, and the two ligand molec ules are terdentate monodeprotonated. Biological studies have shown th at, for the first time at least up the used doses, a free ligand is ac tive both in the inhibition of cell proliferation and in the induced d ifferentiation on Friend erythroleukemia cells (FLC). (C) 1997 Elsevie r Science Inc.