The influence of electronic, steric and hydrophobic properties of flavonoid compounds in the inhibition of the xanthine oxidase

Xanthine oxidase (XO) is an enzyme with the capacity of catalyzing the changing of hypoxanthine in xanthine. Afterwards, the xanthine is transformed in urate which in high levels is responsible for several diseases such as gout, renal diseases and stone formation in the urinary system. Allopurinol is a powerful inhibitor of the XO enzyme and it is used as a medication in cases where it is necessary to inhibit the XO enzyme action. In the literature, several flavonoid compounds have been described as inhibitors of the XO enzyme in a similar way that presented by allopurinol. In this work, a study on the influence of electronic, steric and hydrophobic properties of some flavonoid compounds in inhibiting the XO activity was carried out by using molecular mechanics (MM +) and semi-empirical (AM1) methods. From the results obtained, we were able to correlate the molecular properties of the flavonoid compounds studied with the inhibition of the XO. (C) 2004 Elsevier B.V. All rights reserved.