Inhibition of jack bean urease by phosphoric-and thiophosphorictriamides

Three phosphorictriamides and two thiophosphorictriamides were tested for their urease inhibitory activities by using jack bean urease in an enzyme assay. The phosphorictriamides were N-(n-butyl)phosphorictriamide (NBPTO), cyclohexylphosphorictriamide (CHPT) and phosphoryltriamide (PT), and the thiophosphorictriamides were N-(n-butyl)thiophosphorictriamide (NBPT) and thiophosphoryltriamide. The assay technique used provided a relatively quick assessment of the effectiveness of the compounds tested to inhibit jack bean urease. NBPTO was a more effective inhibitor of jack bean urease than CHPT and PT. The concentrations of NBPTO, CHPT and PT required for 50% inhibition under the conditions of the experiment were 0.2, 6 and 23 μm, respectively. Evaluation of these compounds at various concentration ranges showed NBPTO and CHPT to be promising urease inhibitors.