Bioactivity-guided fractionation of the CH2Cl2 extract from leaves of Piper malacophyllum using bioautography assay against fungi, led to the isolation of two known bioactive piperolides: 4,6-dimethoxy-5-E-phenylbutenolide (1) and 4,6-dimethoxy-5-Z-phenylbutenolide (2). IR, MS and NMR spectroscopic data were used for the identification of these compounds including comparison with previously reported data. The E configuration is associated to higher activity for compound 1, since the minimum amount required for the growth inhibition of Cladosporium cladosporioides and C. sphaerospermum were 1.0/1.0 mug (1) and 5.0/10.0 mug (2), respectively.
Piper malacophyllum; piperolides; antifungal activity