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Determination by NMR methods of the structure and stereochemistry of astellatol, a new and unusual sesterterpene

✍ Scribed by Ian H. Sadler; Thomas J. Simpson

Publisher
John Wiley and Sons
Year
1992
Tongue
English
Weight
467 KB
Volume
30
Category
Article
ISSN
0749-1581

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✦ Synopsis

Abstract

The full structure of astellatol, a new complex sesterterpene isolated from Aspergillus variecolor, was determined solely by the use of one‐ and two‐dimensional NMR techniques. The carbon skeleton was deduced from a two‐dimensional INADEQUATE spectrum, and the proton shifts were deduced from a two‐dimensional CH correlation (HMQC) experiment. Analysis of a two‐dimensional proton DQFCOSY spectrum and a series of homonuclear NOE difference spectra allowed the determination of the full stereochemistry.

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