PUB - Publikationen an der Universität Bielefeld

Chemical investigation of Allophylus africanus P. Beauv fruits led to the isolation of a new delta-tocotrienol, 3alpha-hydroxy-delta-tocotrienol (1) together with eight known compounds (2-9). Compound (1) was allylated (1a) and prenylated (1b and 1c) to give three new semi-synthesized derivatives which were fully characterized as: 6-O-allyl-3alpha-hydroxy-delta-tocotrienol (1a), 6-O-prenyl-3alpha-hydroxy-delta-tocotrienol (1b) and 6-O,5-C-diprenyl-3alpha-hydroxy-delta-tocotrienol (1c). The structures of compounds were established using comprehensive spectroscopic analysis including UV, MS, 1D NMR, 2D NMR and by comparison with the corresponding literature data. Compound (1) and its semi-synthetic derivatives (1a-c) were tested for their antioxydant activity using DPPH radical scavenging assay and also for their cytotoxicity using human cervix carcinoma KB-3-1 cell lines. The results showed that compound (1) exhibited antioxidant activity with an IC50 value of 0.25muM compared to the reference control trolox (26M); and good cytotoxic activity with IC50 values of 97muM compared to the reference (+)-griseofulvin (IC50 between17-21muM).