Tuscolid and Tuscoron A and B: Isolation, Structural Elucidation and Studies on the Biosynthesis of Novel Furan-3(2H)-one-Containing Metabolites from the Myxobacterium Sorangium Cellulosum

✍ Scribed by Jutta Niggemann; Martina Herrmann; Klaus Gerth; Herbert Irschik; Hans Reichenbach; Gerhard Höfle

• Publisher: John Wiley and Sons
• Year: 2004
• Tongue: English
• Weight: 143 KB
• Volume: 2004
• Category: Article
• ISSN: 1434-193X
• DOI: 10.1002/ejoc.200300539

✦ Synopsis

Abstract

Three novel metabolites, tuscolid (1) and tuscoron A (2) and B (3), were isolated from the myxobacterium Sorangium cellulosum (strains So ce1401 and So ce1383). The structures were elucidated by detailed NMR spectroscopic analysis, and their biosynthesis was studied by feeding ^13^C‐labelled precursors. The results revealed that the macrolide 1 and the acyclic derivative 2 are closely related polyketides containing, as a characteristic structural feature, a furan‐3(2__H__)‐one ring system. The related minor component tuscoron B (3) was identified as an unstable structural analogue of tuscoron A. The relative stereochemistry of the tetrahydropyran ring and of C‐13 to C‐17 of tuscolid (1), and of the dihydropyran ring of tuscoron A (2), was determined on the basis of ^1^H‐^1^H‐coupling constants and NOE correlations. A tentative mechanism for the conversion of 1 into 2 is discussed. (© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2004)