Synthesis, structural properties and DNA protective activity of ferrocenyl N‐acyl pyrazolines

Abstract

Two series of new ferrocenyl pyrazolines have been synthesized by the reaction of ferrocenyl chalcones and their analogues with hydrazine hydrate in the presence of corresponding carboxylic acid. Single‐crystal X‐ray crystallographic data were used for detailed analysis of the interesting versatility of four compounds in the formation of intermolecular interactions. The analysis revealed an excellent structural flexibility of the present ferrocenyl pyrazoline molecules for the non‐covalent interactions, with a particular contribution of the ferrocene units. In addition, for comparison with crystallographic findings, we investigated the protective effect of all compounds on DNA against hydroxyl and peroxyl radicals induced by Fe2+, H2O2, and 2,2′‐azobis(2‐amidinopropane) dihydrochloride (AAPH). The results indicated that all compounds showed rather similar DNA protective activity, which was comparable with quercetin as a well‐known protective compound. This similarity in antigenotoxic action could be explained by the established excellent structural flexibility of ferrocenyl pyrazolines for the formation of different intermolecular interactions as important structural property for molecular recognition.