1426385-33-2Relevant academic research and scientific papers
Substituted 2,2′-bipyrroles and pyrrolylfurans via intermediate isoxazolylpyrroles
Frederich, James H.,Matsui, Jennifer K.,Chang, Randy O.,Harran, Patrick G.
, p. 2645 - 2647 (2013/06/26)
We describe a new synthesis of the 3-chloro-(4′-methoxy)-2,2′- pyrrolylfuran segment (3) of (+)-roseophilin. The route exploits a isoxazoylpyrrole intermediate, wherein the isoxazole ring serves as a β-diketone equivalent and a directing group for palladium catalyzed chlorination of the attached pyrrole. Subsequent reduction of the N-O bond and acid promoted cyclization afford roseophilin segment 3b in five steps and 19% overall yield. This strategy was extended to the synthesis of 3-chloro-(4′-alkoxy)-2,2′-pyrrolylfurans (16a-c) and 4-alkoxy-2,2′-bipyrroles (20a-c), which are building blocks to synthesize bioactive prodiginine natural products and their congeners.
Modular access to complex prodiginines: Total synthesis of (+)-roseophilin via its 2-azafulvene prototropisomer
Frederich, James H.,Harran, Patrick G.
, p. 3788 - 3791 (2013/04/10)
Ansa-bridged prodiginines are bioactive pigments produced by bacteria. Certain of these structures are reported to be antagonists of protein-protein interactions involved in apoptosis. We describe a new entry to alkaloids of this type, demonstrated with a concise asymmetric synthesis of (+)-roseophilin (3). Our route constructs the pyrrolophane motif via phosphoryl transfer-terminated macroaldolization and passes through a previously unexplored prototropic form of the natural product.
