Regiospecific, short, and efficient synthesis of the naturally occurring anthraquinones islandicin (la), digitopurpone lb), erythroglaucin (IC), catenarin (ld), cynodontin (le), and soranjidiol (If) have been achieved in 20-30% overall yields by using directed metalation of easily accessible methoxylated N, N-diethylbenzamides (3 and 10a--d) as the key step. In a representative example (Scheme IV), sequential treatment of N, N-di-ethyl-3, 5- ...
