Synthetic Studies on Actinorhodin and γ-Actinorhodin: Synthesis of Deoxyactinorhodin and Deoxy-γ-actinorhodin/Crisamicin A Isomer

A strategy based on bidirectional Dotz benzannulation and the oxa-Pictet-Spengler reaction toward the synthesis of actinorhodin and -actinorhodin has been explored. This work has resulted in the synthesis of deoxyactinorhodin and deoxy--actinorhodin. The latter is a regioisomer of crisamicin A (which has 10,10-dihydroxy groups).