Application of a 6π-1-Azatriene Electrocyclization Strategy to theTotal Synthesis of the Marine Sponge Metabolite Ageladine A andBiological Evaluation of Synthetic Analogues
A 12-step synthesis of the angiogenesis inhibitory marine metabolite ageladine A is reported. The keysteps include a 6π-1-azatriene electrocyclization for formation of the pyridine ring and a Suzuki−Miyauracoupling of N-Boc-pyrrole-2-boronic acid with a chloroimidazopyridine. In addition, an assessment ofthe biological activity of a variety of synthetic analogues of ageladine A prepared during this synthesisis described.