A study was performed on xanthine-oxidase inhibition by 22 flavonoids, incl
uding flavones, flavonols, flavanones, and chalcones, using UV spectroscopy
for experimental data and molecular topology to establish the structure-ac
tivity relationship (SAR) model. The flavonoids were classified into four g
roups according to their activity on xanthine-oxidase (inactive, low, signi
ficant, or high), and linear discriminant analysis was used to classify eac
h compound within a group. The results led to a very good model, which was
able to classify correctly as xanthine oxidase inhibitors, along with a tes
t set of molecules including a variety of different compounds such as allop
urinol, caffeic acid, esculetin, and alloxantin.