An eco-friendly electrochemical process for the formation of a new desloratadine derivative and its antibacterial susceptibility. Report of a new type of ortho-quinhydrone complex

Abstract

In this work, the synthesis of a new derivative of desloratadine (DQ-TBC complex) was carried out for the first time by a green electrochemical method. In order to create optimal conditions for the electrochemical synthesis of DQ-TBC complex, electrooxidation of 4‑tert-butylcatechol (TBC) was studied in the absence and presence of desloratadine (DES). To discover the reaction mechanism, the effects of solution pH, concentration of DES and potential scan rates were investigated using cyclic voltammetry and chronoamperometry techniques. The results suggest that the electrooxidation of TBC in the presence of DES leads to DQ through an ECE mechanism. This compound (DQ) is converted to the ortho-quinhydrone complex (DQ-TBC complex) as the final product after participating in a noncovalent interaction (hydrogen bonding) with TBC. The desired product was successfully synthesized in an ethanol/water mixture in a divided cell, at room temperature using carbon electrode (five ordinary soft carbon rods with total area 38 cm2) as the anode. The final product was identified by cyclic voltammetry, FTIR, NMR, Mass spectroscopic and thermogravimetric methods. Moreover, the synthesized compound was tested for antibacterial activity. The results indicated that DQ-TBC complex shows promising antibacterial activity against Bacillus cereus and Staphylococcus aureus, gram-positive bacteria.