view:32741 Last Update: 2022-5-4
Narges Pakravan, Hassan Shayani-Jam⁎, Hadi Beiginejad, Hadis Tavafi, Shadi Paziresh
A green method for the synthesis of novel spiro compounds: Enhancement of antibacterial properties of caffeic acid through electrooxidation in the presence of barbituric acid derivatives
In this work, the novel Spiro cycles with high potential antibacterial activity were synthesized via a one-pot and environmentally friendly electrochemical approach, without toxic reagents and solvents. In the first, electrochemical oxidation of caffeic acid (1) in the presence of barbituric acids (3a-c) as nucleophiles have been studied using cyclic voltammetry and controlled-potential coulometry. The obtained electrochemical results demonstrate that an electrooxidative/Michael-type sequential reaction occurs between the barbituric acids and the caffeic acid o-quinone produced by electrooxidation of caffeic acid leading to the corresponding novel Spiro cycles (8a-c). The mechanism of the electrochemical reaction was suggested as an ECEC (Electron transfer, Chemical reaction, Electron transfer, Chemical reaction) pathway using cyclic voltammetry, controlled-potential coulometry and spectroscopic data. The antibacterial activities of the synthesized compounds were investigated and compared with caffeic acid and barbituric acids.