Studies Towards The Synthesis Of Antibiotic Rubradirin Macrocycle

In recent years, the abuse of antibiotics has been threatening the health of humans. It is significant to study new and effective antimicrobial agents. Rubradirin is highly active against a variety of Gram-positive bacteria and especially it shows activity(MIC = 125 nM) against the increasingly important multiply-antibiotic resistant strains of Staphylococcus aureus. Our project has developed the concise synthesis of Rubradirin macrocycle, it includes(i) Formation of ring A and ring B via an intermolecular Diels-Alder reaction;(ii) Synthesis of ring C through reductive amination and one pot tandem reaction(OsO4-catalyzed dihydroxylation, Michael addition and oxidation). Also, we attempted to close D ring via Grubbs II catalyzed RCM reaction to form the macrocycle of Rubradirin. Finally, we have constructed the ABC ring via efficient and practical route, which contributes to the total synthesis of Rubradirin.