Synthesis of 3,4,5-trihydroxybenzohydrazone and evaluation of their urease inhibition potential

Abstract

In the continuation of our work to synthesize enzyme inhibitors, we synthesized 3,4,5-trihydroxybenzohydrazones (1–19) from 3,4,5-trihydroxybenzohydrazide, which were obtained from methyl 3,4,5-trihydroxybenzoate by refluxing with hydrazine hydrate. All the synthesized compounds were characterized by different spectroscopic methods. The synthesized compounds were evaluated for urease inhibition and showed excellent results, close to the standards thiourea. The kinetic studies on the five most active compounds 6, 10, 14, 16 and 18 were carried out to determine their mode of inhibition and dissociation constant Ki. The compounds 6 and 16 were found to be competitive inhibitors with Ki values 19.1 and 10.53 μM, respectively, while the compounds 10, 14 and 18 were found to be mixed-type of inhibitors with Ki values in the range of 18.4–21.7 μM. Keywords: 3,4,5-Trihydroxybenzohydrazones, Urease inhibition, Kinetic study