Antifungal chalcones from Maclura tinctoria

Five prenylated flavonoids, including one new natural product, were isolate d 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"-methy lbut-3 "-enyl]-chalcone (1). The known compounds were identified as 2'4'4-t rihydroxy-3'-[3"-methylbut-3"-enyl]chalone (isobavachalcone) (2), 4,2'-dihy droxy-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-diprenylisof lavone (6,8-diprenylorobol) (5). All the isolated compounds were evaluated against the AIDS-related opportunistic fungal pathogens, Candida albicans a nd Cryptococcus neoformans. Compound 2 was active against both yeasts.