2-Anthracenonyl Acetic Acids as 5-Lipoxygenase Inhibitors

The synthesis of 2-substituted anthracenonyl acetic acid (2-AA) derivatives is described. The key step is the Marschalk reaction of 1-hydroxy-8-methoxy-anthracenedione with glycolic acid. After protection of the resulting 2-anthracenonyl acetic acid derivative, the 2-monoalkylated derivatives are selectively obtained by direct alkylation. The methodology proves quite general and allows for the introduction of various substituents onto the 2-position of the carboxylic side chain. Reduction of the anthracenediones proceeds with concomitant protecting group removal and provides final 2-AA products in good yields. The results of initial biological studies demonstrate enhanced 5-lipoxygenase inhibition compared to anthralin.