Two New 5-Deoxyflavones from Albizia odoratissima

Abstract

Two new 5-deoxyflavones, 7,8-dimethoxy-3′,4′-methylenedioxyflavone (1) and 7,2′,4′-trimethoxyflavone (2) together with a known flavone, 7,4′-dimethoxy-3′-hydroxyflavone (3) were isolated from the rootbark of Albizia odoratissima. The structures of these new compounds were elucidated by electrospray ionization mass spectrometry (ESI-MS) and 1D and 2D-NMR spectral studies including ¹H–¹H correlation spectroscopy (COSY), heteronuclear single quantum coherence (HSQC), heteronuclear multiple bond connectivity (HMBC) and nuclear Overhauser enhancement spectroscopy (NOESY).