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A new phenylheptanoid from the leaves of Gnetum gnemon L
Tho Huu Le1,2, Truong Nhat Van Do1,2, Hai Xuan Nguyen1,2
1Faculty of Chemistry, University of Science, Ho Chi Minh City, Vietnam.
Abstract:
Phytochemical study on the EtOAC-soluble extract of the leaves of Gnetum gnemon furnished the isolation of a new phenylheptanoid, gnetumal (1), along with five known compounds (2-6). Their isolation was carried out by using the column chromatography and their structures were elucidated based on the basis of the spectral interpretation. Bioactivity assay of these compounds indicated that gnetumal (1) and p-coumaric acid (5) possessed more potent tyrosinase inhibitory activity, with IC50 values of 31.6 and 2.3 µM, respectively, than that of a positive control kojic acid (IC50; 44.6 µM).
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