The ¹H-and 13C-NMR spectral data of 1,6-dihydroxy-5-(3-methylbut-2-enyl)-6’,6’-dimethyl-pyrano(2’,3’;7,8)-6",6"-dimethyl-pyrano(2",3";3,2) xanthone and 1,3,6-trihydroxy-6’,6’-dimethyl-pirano(2’,3’;7,8)-2,5-di-(3-methylbut-2-enyl)xanthone have been unambiguously assigned by the analysis of homonuclear (¹H-¹H-COSY) and heteronuclear [¹H-13C-COSY: modulated with ¹J CH and nJ CH (n = 2 and 3, COLOC)] shift-correlated and NOE difference spectra.
