Evaluation of the antioxidant and cryoprotective activity of bicyclic pyrrolidine derivatives with a 2,6-di-tert-butylphenol fragment

The studies of the antioxidant and cryoprotective activities of bicyclic pyrrolidine derivatives containing a 2,6-di-tert-butylphenol fragment in the in vitro experiments showed the greater activity of these compounds compared to ionol. The analysis of the kinetic profile of the reactions of these compounds with 2,2-diphenyl-1-picrylhydrazyl radical (DPPH test) and radical cation of 2,2′-azinobis(3-ethylbenzothiazoline-6-sulfonic acid) showed that the first step consisted in the rapid single electron transfer (SET), which was followed by the hydrogen atom transfer (HAT). The high activity in the reaction of Fe³⁺ reduction (FRAP test) was characteristic of methyl (1S*,3R*,3aS*,6aR*)-3-(3,5-di-tert-butyl-4-hydroxyphenyl)-1-methyl-5-(2-nitrophenyl)-4,6-dioxooctahydropyrrolo[3,4-c]-pyrrole-1-carboxylate. The compounds under study were found to be able to terminate chain reactions due to the chelation of metals involved in the Fenton reaction. The compounds also exhibited prolonged antioxidant activity under autoxidation conditions and conditions of oxidative stress promoted by FeCl₂. An increase in the viability of reproductive cells of sturgeon breeds in the presence of the pyrrolidine derivatives indicated the possibility of their use as promising antioxidant protectors during hypothermic storage and under conditions of deep freezing of germ cells of economically valuable fish species.