The chemical investigation of the methanol root extract of Artocarpus heterophyllus Lam. led to the isolation of a new prenylated flavanone, 5,7,4'-trihydroxy-3'-(3-methylbuta-1,3-dienyl)-5'-(3-methylbut-2-enyl)flavanone, trivially named maghamesin (1), together with nine known compounds, 5-hydroxy-3',4',5',7-tetramethoxy-8-prenylflavanone (2), cycloheterophyllin (3), cyclomorusin (4), isobavachalcone (5), trans-isoferulic acid (6), 24-methylenecycloartan-3α-ol (7), stigmasterol (8), β-sitosterol (9) and β-sitosterol-3-O-β-D-glucopyranoside (10). The structures of the isolates were elucidated by extensive spectroscopic and spectrometric analyses (1D and 2D NMR, ESI-MS) and by comparison with previously reported data. The absolute configuration of 1 was deduced by comparison of its experimental CD with that of a reported similar compound. Compounds 1-3 and 6-7 were tested for their antibacterial and antifungal activities. Compound 1 displayed a significant antibacterial activity against Staphylococcus aureus with MIC value of 15.625 μg/mL. The others tested compounds showed moderate antibacterial and antifungal activities against several microorganisms with MIC values of either 31.25 or 62.5 μg/mL.
Keywords: Artocarpus heterophyllus lam; antibacterial activity; antifungal activity; moraceae; prenylated flavanone.