Anthralin [1,8-dihydroxy-9(10H)-anthracenone] is among the most
widely used drugs in the topical treatment of psoriasis1). However, not
much is known concerning its mode of action at the molecular level,
although a variety of cellular targets have been implicated both in the main
and side effects of anthralin2 ). In particular, the interaction of anthralin
with proteins has long been recognized to occur3 , 4 ) and there has been
renewed interest in this topic, mostly directed toward the investigation
whether enzyme inhibition by anthralin is related to oxygen radicalmediated
damage of proteins5 ) . In order to gain a more profound
understanding of the interaction between this drug and cellular targets,
anthralin labelled with a non-exchangeable radioisotope in a suitable
position was highly desirable. Furthermore, this labelled compound might
serve as a useful starting material for the synthesis of analogues labelled in
the anthrone nucleus. Since structural modification of anthralin has
provided compounds with improved biological activity6 '7), labelled
compounds are required for studies on skin penetration and metabolism of
these future drugs.
Although routes to 14C-anthralin have already been described8,9), each of
these methods suffers from too many synthetic steps, or the use of
hazardous 14C-sources1 ) . In this paper, we describe a short and efficient
synthesis of l,8-dihydroxy-[10-14C]-9(10H)-anthracenone.