In vitro inhibition of polyphenol oxidase by some new diarylureas

Abstract

A new series of N,N′-diarylureas (19) was synthesized. These compounds were investigated as inhibitors of polyphenol oxidase (PPO) which had been purified from banana by an affinity gel comprised of Sepharose 4B-l-tyrosine-p-amino benzoic acid. Ki values for (1), (2), (3), (5), (6), (7) and (8) were determined as 0.285, 17.97, 0.187, 0.108, 0.063, 0.044 and 0.047mM, respectively. Thus (2) was by far the most effective inhibitor. Interestingly, (4) and (9) behaved as an activator of PPO in this study. © 2012 Informa UK, Ltd.