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R-Hexitronic acid, a new tetronic acid derivative isolated from a soil fungus FG9RK
Kenneth G Ngwoke1,2, Dina H El-Kashef1,3, Georgios Daletos1
1Institute of Pharmaceutical Biology, Heinrich Heine University, Duesseldorf, Germany.
Abstract:
A new tetronic acid derivative (1) together with terrestric acid (2), a known metabolite of Penicillium species, was isolated from the soil fungus, FG9RK following fermentation on solid rice medium. The structure of 1 was elucidated by one- and two-dimensional NMR and MS measurements. The absolute configuration of the oxygenated carbon in the side chain of 1 was identified as S by converting the compound into its Mosher ester whereas the absolute configuration of the lactone ring was deduced based on biogenetic considerations and comparison with 2.
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