Oxidative biosynthesis of phenylbenzoisochromenones from phenylphenalenones.

Max-Planck-Institut für Chemische Okologie, Beutenberg Campus, Winzerlaer Str. 10, D-07745 Jena, Germany.
Phytochemistry (Impact Factor: 3.05). 03/2003; 62(3):307-12. DOI: 10.1016/S0031-9422(02)00546-0
Source: PubMed

ABSTRACT 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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