Electrolytic macrocyclizations: scalable synthesis of a diazonamide-based drug development candidate.

An electrochemical method to synthesize the core macrolactam of diazonamides is described. Large ring-forming dehydrogenation is initiated by anodic oxidation at a graphite surface. The reaction requires no tailoring of the substrate and occurs at ambient temperature in aqueous DMF in an undivided cell open to air. This unique chemistry has enabled a concise, scalable preparation of DZ-2384; a refined analog of diazonamide A slated for clinical development as a cancer therapeutic.

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