Short, Scalable Access to Pyrrovobasine

A concise, gram-scale synthesis of pyrrovobasine (1) is reported. Key transformations include a 3-step decagram-scale synthesis of the tetracyclic compound without protecting groups, Mn-mediated direct radical cyclization, and introducing a naturally rare pyrraline structure. The synthesis is designed to be applicable to gram-scale synthesis using inexpensive and readily available reagents.