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Updated: Jan 15, 2026

On-line Analysis of Nitrogen Containing Compounds in Complex Hydrocarbon Matrixes
Published on: August 5, 2016
An efficient stereochemical elucidation of the aromatic polyketide NFAT-133 using the novel NOE quantification
Kazuo Furihata1, Yusuke Ogura1, Hirosato Takikawa1
1Department of Applied Biological Chemistry, Graduate School of Agricultural and Life Sciences, The University of Tokyo, Tokyo, Japan.
Abstract:
NFAT-133, which was isolated from Streptomyces sp., is an immunosuppressive and antidiabetic aromatic polyketide containing three contiguous stereocenters. Although its absolute configuration was first proposed mainly based on NMR data, the later study employing the total synthesis of the proposed structure and its epimer resulted in the stereochemical revision of NFAT-133. The difficulty of determining relative configuration in polyketides arises from spin systems consisting of a methine group directly bonded to a methyl group (e.g. -CH(OH)-CH(CH3)-CH(OH)-). In this case, the stereochemical analysis of the aforementioned chain structure is generally hard due to the limited information of nJC-H and nJH-H. In an aim of developing a reliable analytical method based on NMR spectroscopy, we applied a novel NOE quantification in a 1D double pulsed field gradient spin echo (DPFGSE)-NOESY spectra. The combinational analysis of the proposed NOE quantification with nJC-H and nJH-H provided an accurate determination of the relative configurations.
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