Heterogeneous organic compounds play an important role in our daily life as they contribute in many medical and industrial fields and are in continuous development as a result of the preparation of new derivatives with different properties. From this premise, the goal of this work appears, which is preparation of (four, five, six, and seven) membered ring systems derived from furfural, by its reaction with different aromatic aldehydes, and record their antioxidant activity by using free radical scavenging method of DPPH radicals. The new ring systems are synthesized by reacting the prepared Schiff-bases with different ring closure agents (chloroacetyl chloride, mercaptoaceticacid, anthranilic acid, and phthalic anhydride), the prepared compounds were characterized by measuring their melting points and recording their infrared spectra in addition to the NMR spectra for some of them, the recorded results for some derivatives were higher when comparing them with ascorbic acid as a drug because these compounds have electrons that are able to terminate the free radicals that cause the oxidation process.
