Novel ferrocene conjugates of tricyclic quinazoline derivatives are prepared by condensation of active C-6 methylene groups of mackinazolinones with ferrocenecarbaldehyde. Following this route the conjugated parent alkaloid as well as derivatives with nitro, amino, and alkanoylamino groups at C-2 were attached at the ferrocene moiety, thereby significantly extending the delocalized π system. In addition, the parent compound was subjected to the reaction with ferrocene-1,1'-dicarbaldehyde, giving rise to the symmetrical and unsymmetrical double condensation products – 1,1'-disubstituted ferrocene derivatives, which bear two alkaloid substituents. Some of the compounds obtained were subjected to X-ray crystallographic analyses. The influence of the substituents at C-2 through the extended conjugated π system on the iron atom is reflected by results of cyclovoltammetric measurements.
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