Antibacterial and antifungal flavanones from Eysenhardtia texana

An activity-guided fractionation of a methanol-dichloromethane extract obta ined from the aerial parts of Eysenhardtia texana led to the isolation of t wo novel antibacterial and antifungal flavanones together with a known flav anone. Their structures were established as 4',5,7-trihydroxy-8-methyl-6-(3 -methyl-[2-butenyl])-(2S)-flavanone, 4',5,7-trihydroxy-6-methyl-8-(3-methyl -[2- butenyl])-(2S)-flavanone and 4',5-dihydroxy-7-methoxy-6-(3-methyl-[2-b utenyl])-(2S)-flavanone on the basis of their UV, 1D and 2D-NMR spectra. (C ) 1999 Elsevier Science Ltd. All rights reserved.