Synthesis and Identification of New ۲-Substituted-۱,۳,۴-Oxadiazole Compounds from Creatinine and Study Their Antioxidant Activities

The synthesis of many new ۲-substituted ۱,۳,۴-oxadiazoles from creatinine is studied in this research. The ester of creatinine ۱a was formed by the reaction of creatinine with ethylchloroacetate, and then with two of alkyl halides to produce compounds ۲a-۲b. Following that, hydrazide derivatives ۳a-۳b were produced by compounds ۲a-۲b with semicarbazide hydrochloride. These hydrazides were cyclized with ۵ percent sodium hydroxide to produce ۱,۳,۴-oxadiazole derivatives ۴a-۴b. The reaction of these compounds with aromatic aldehydes produced Schiff bases ۵a-۵d. Finally, diazetidine ۶a-۶h and β-lactam ۷a-۷d derivatives on position (۲) from ۱,۳,۴-oxadiazole were formed by reacting Schiff bases with various reagents. FT-IR spectroscopy and ۱H-NMR for some synthesized compounds were used to identify the newly synthesized compounds. In vitro, antioxidant activities of some synthesized compounds were also investigated with promising results.