[Influence of Hydroxy-1,4-naphthoquinone Derivatives on Prostaglandin synthesis (author's transl)]

Inhibition of cyclo-oxygenase reaction during prostaglandin formation in the renal medulla of the rat by 1,4-naphthoquinone derivatives is compared with the known enzyme inhibition properties of natural and synthetic flavonols. Structure-activity relationship study shows strong correlation between chemical properties (vicinal hydroxy-oxo structure of planar molecules) and physicochemical parameters (polarity and acidity). The most potent compounds are 2-ethyl-5-hydroxy-1,4-naphthoquinone (9) and 2-methyl-3-hydroxy-1,4-naphthoquinone (6).