Flavan derivatives. XIX. Teracacidin and isoteracacidin from Acacia obtusifolia and Acacia maidenii heartwoods; Phenolic hydroxylation patterns of heartwood flavonoids characteristic of sections and subsections of the genus Acacia

Abstract

7,8,4?-Trihydroxyflavonol and (-)-cis-cis-7,8,4?-trihydroxyflavan-3,4- diol (teracacidin) have been isolated from the heartwoods of A. obtusifolia and A. maidenii; a flavanone and a dihydroflavonol (presumably 7,8,4?-trihydroxyflavonoids) were also detected in the heartwood extracts. trans-4-Hydroxy-L-pipecolic acid was isolated from A. maidenii heartwood. The hydroxylation patterns of flavonoids in the heartwoods of Australian Acacia species examined have been found to be characteristic of the sections and subsections within the genus. The flavonols from the heartwoods of A. flavescens, A. havilandii, A. oswaldii, A.pendula, A. rhodoxylon, and A. shirleyi were identified by paper chromatography.