Natural product synthesis with unnatural results: Characterization of a novel fused imidazolidinone tetrahydropyrroloindole ring system by long-range 1H-15N 2D-NMR

✍ Scribed by Chad E. Hadden; David J. Richard; Madeleine M. Joullié; Gary E. Martin

• Publisher: Journal of Heterocyclic Chemistry
• Year: 2003
• Tongue: English
• Weight: 52 KB
• Volume: 40
• Category: Article
• ISSN: 0022-152X
• DOI: 10.1002/jhet.5570400227

✦ Synopsis

Abstract

Synthetic efforts towards the indole alkaloid natural product roquefortine C resulted in the formation of an unknown intermediate. Elucidation of the structure of this molecule relied on the use of long‐range ^1^H‐^15^N 2D‐NMR. Computational predictions were used to facilitate the location of weak responses in long‐range ^1^H‐^13^C HMBC spectra. These methods provided conclusive evidence that this compound possessed a novel tetracycle. The complete ^12^H, ^13^C, and ^15^N chemical shift assignments of this unique fused imidazolidinone tetrahydropyrroloindole derivative are reported.