The synthesis of 1,3‐dihydro‐1‐[1‐[(4‐methyl‐4H‐6H‐pyrrolo[1,2‐a][4,1]benzoxazepin‐4‐yl)methyl]‐4‐piperidinyl]‐2H‐benzimidazol‐2‐one (1:1) maleate (CGS 9343 B, potent calmodulin inhibitor)

A practical synthesis of the title compound 7b is described in seven steps in approximately 10% overall yield. The key step in the synthesis is the formation of the unusual tricyclic ring system 4 via acid catalyzed cyclization. Copyright © 1988 Journal of Heterocyclic Chemistry