Solvent-free mechanochemical green synthesis of Schiff bases of tranexamic acid and study of their urease inhibitory and antioxidant activities

Three Schiff bases of tranexamic acid were successfully synthesized by a mechanochemical green method, which is 4-{(5-bromo-2- hydroxybenzylidene)amino]methyl}cyclohexanecarboxylic acid (SB1), 4-{(2-hydroxybenzylidene)amino]methyl}cyclohexanecarboxylic acid (SB2), and 4-{(4-nitrobenzylidene)amino]methyl}cyclohexanecarboxylic acid (SB3) in good yield. Their structures were confirmed based on spectroscopic data. The bases displayed considerable urease inhibitory activity with IC50 (µg/mL) 33.41, 40.64, 26.18, and 11.14 for SB1, SB2, SB3, and standard thiourea, respectively. They revealed weak antiradical activity in DPPH assay with EC50 (µg/mL) 1138, 1239, and 24248 for SB1, SB2, and SB3, respectively. In conclusion, grinding is an efficient and environmentally friendly method for synthesizing these bases, which may provide potential candidates for new medicines.

Solvent-free mechanochemical green synthesis of Schiff bases of tranexamic acid and study of their urease inhibitory and antioxidant activities Keywords:

Tranexamic acid derivatives , bioactivities , Green chemistry , Grinding method