Synthesis of anti-rheumatic agent epoxyquinomicin B

Anti-rheumatic agent (±)-epoxyquinomicin B was synthesized for a 22% overall yield in eight steps from commercially available 3-hydroxy-4-nitrobenzaldehyde via the intermediate quinone 6 prepared by selective phenol oxidation of 5 by use of Fremyʹs salt as the key step.