Antifungal chalcones from Maclura tinctoria.

Five prenylated flavonoids, including one new natural product, were isolated from an ethanol extract of the leaves of Maclura tinctoria (L.) Gaud. The new compound has been characterized as 2',4',4,2''-tetrahydroxy-3'-[3''-methylbut-3''-enyl]chalcone (1). The known compounds were identified as 2',4',4-trihydroxy-3'-[3''-methylbut-3''-enyl]chalcone (isobavachalcone) (2), 4,2'-dihydroxy-2''-[1-hydroxy-1-methylethyl]-2'',3''-dihydrofurano[4'',5'':3',4']chalcone (bakuchalcone) (3), 4,4',5''-trihydroxy-6'',6''-dimethyldihydropyrano[2'',3'':5',6'']chalcone (bavachromanol) (4), and 5,7,3',4'-tetrahydroxy-6,8-diprenylisoflavone (6,8-diprenylorobol) (5). All the isolated compounds were evaluated against the AIDS-related opportunistic fungal pathogens, Candida albicans and Cryptococcus neoformans. Compound 2 was active against both yeasts.