Phytochemical investigation from wood residues of Dalbergia spruceana Benth

Abstract

Dalbergia spruceana Benth (Fabaceae: Papilionoideae), known in the Brazilian Amazon as ¨jacarandá-do-pará” recognized for the natural resistance of its wood has little scientific information about its secondary metabolism. In this paper, we report a phytochemical study of the wood residues of D. spruceana using classical chromatographic techniques. Thus, the chromatographic fractionation of methanolic extract resulted in the isolation of phenylpropanoid, isoflavonoids of different types (pterocarpan, isoflavonol, isoflavan, isoflavone) in addition to a neoflavonoid. A new isoflavonoid with an oxygenation pattern not previously reported was elucidated as 8,4,2'-trihydroxy-7,4'-dimeth-oxyisoflavonol. The structures of all the isolated compounds were determined by using 1D- and 2D-NMR techniques, mass spectrometry ESI-MS and by comparison with literature data. Most of the compounds that were identified are isoflavonoids, which are types of flavonoids that are especially recognized for their contribution to the natural resistance of the wood.