New bis-catechols 5-lipoxygenase inhibitors

Three polyhydroxy-2-phenylnaphthalenes (1-3) and the oxy analogue of tetrah ydroxypavinan (4) were prepared and evaluated for their antioxidant propert ies (inhibition of diphenylpycrylhydrazyl radical (DPPH), reduction of iron (III) ion) and inhibition of 5-lipoxygenase (5-LO) activity. Their three-d imensional structures were established on the basis of spectroscopic data a nd semi-empirical calculations. Compounds 1 and 2 were found as potent 5-LO inhibitors as nordihydroguaiaretic acid (NDGA), whereas 4 is 2.5 times les s potent than NDGA. The reliability of the 3-D structures with the 5-LO inh ibition properties is discussed. Their antioxidant properties show that tes ted compounds are expected to act as redox inhibitors. (C) 2001 Elsevier Sc ience Ltd. All rights reserved.