Oxidative biosynthesis of phenylbenzoisochromenones from phenylphenalenones

Max Planck Institute for Biogeochemistry Jena, Jena, Thuringia, Germany
Phytochemistry (Impact Factor: 2.55). 03/2003; 62(3):307-12. DOI: 10.1016/S0031-9422(02)00546-0
Source: PubMed


13C NMR analysis demonstrated incorporation of two 13C labelled phenylalanine units into phenylphenalenones and phenylbenzoisochromenones co-occurring in Wachendorfia thyrsiflora. These results suggest oxidative formation of phenylbenzoisochromenones following a late branching from a common phenylphenalenone biosynthetic pathway. A dioxygenase-type mechanism, followed by decarboxylation, is suggested for the key steps of this conversion.

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