Dihydrophenanthrene and Phenanthrene Mimics of Natural Compounds—Synthesis and Antialgal Activity

Abstract

9,10-Dihydrophenanthrenes and phenanthrenes, mimics of natural compounds with strong antialgal activity, have been synthesized through cross-coupling of 1-(2-iodo-5-methoxy)-phenylethanol with variously substituted iodobenzenes. The synthetic compounds, bearing a hydroxyl or a methoxyl group at C-2 and a methyl in the C ring, were tested against the green alga Selenastrum capricornutum. All compounds, except 2-methoxy-7-methylphenanthrene, caused inhibition of algal growth by more than 70% at 10−4 M, and many of them retained this strong activity at 10−5 M.