Total synthesis of styelsamine c,and formal synthesis of norsegoline

摘要

Two fused tetracyclic aromatic alkaloids,styelsamine C (3) from the ascidian Eusynstyela latericius,and norsegoline (5) from the marine tunicate Eudistoma sp.,were synthesized using a biaryl cross-coupling reaction.Over the last decade,a series of structurally interesting and biologically active fused polycyclic aromatic alkaloids containing a pyrido[2,3,4-kl]acridine subunit has been isolated from marine sources.