Anti-PKC activity of some 3-(dialkylamino)-1H-naphtho [2,1-b] pyran-1-ones

Some 3-(dialkylamino)-1H-naphtho [2,1-b] pyran-1-ones were tested to evaluate their ability to inhibit Protein Kinase C (PKC) activation. The model consisted in the detection of the superoxide anion in activated neutrophils. Naphthopyrans carrying 3-(diethylamino), 3-(1-piperidinyl) and 3-[bis(2-methoxyethyl)amino] groups emerged as the most active ones. Introduction of alkoxy groups in position 8 and 9 and of bromo substituent in position 8 on the naphthalene moiety was associated with an increase in anti-PKC activity. No activity was found when an electron withdrawing group was placed in position 2 of the 3-(dialkylamino)-1H-naphtho [2,1-b] pyran-1-ones.