Falah S, Suzuki T, Katayama T
Faculty of Agriculture, Kagawa University, 2393 Ikenobe, Miki-Cho, Kagawa 761-0795, Japan.
Pak J Biol Sci. 2008 Aug 15;11(16):2007-12. doi: 10.3923/pjbs.2008.2007.2012.
Chemical constituents of the bark of Swietenia macrophylla King (Meliaceae) was investigated not only to develop further bark utilization but also to understand the biochemical function of the bark in the forest environment. A new phenylpropanoid-substituted catechin, namely, swietemacrophyllanin [(2R*,3S*,7"R*)-catechin-8,7"-7,2"-epoxy-(methyl 4",5"-dihydroxyphenylpropanoate)] (1) was isolated from the bark of S. macrophylla together with two known compounds, catechin (2) and epicatechin (3). The structure of 1 was elucidated by spectroscopic data and by comparison of the NMR data with those of catiguanins A and B, phenylpropanoid-substituted epicatechins. The 1,1-diphenyl-2-picrylhydrazyl (DPPH) free radical scavenging activity of the isolated compounds indicated that all of the three compounds have strong activity compared with trolox as a reference. Swietemacrophyllanin (1) had the strongest activity with a 50% inhibitory concentration (IC50) value of 56 microg mL(-1).
对大叶桃花心木（楝科）树皮的化学成分进行了研究，不仅是为了进一步开发树皮的用途，也是为了了解树皮在森林环境中的生化功能。从大叶桃花心木树皮中分离出一种新的苯丙素取代儿茶素，即大叶桃花心木素[（2R*，3S*，7"R*）-儿茶素-8,7"-7,2"-环氧-（4",5"-二羟基苯丙酸甲酯）]（1），以及两种已知化合物儿茶素（2）和表儿茶素（3）。通过光谱数据并将核磁共振数据与catiguanins A和B（苯丙素取代表儿茶素）的数据进行比较，阐明了1的结构。分离得到的化合物的1,1-二苯基-2-苦基肼（DPPH）自由基清除活性表明，与作为参考的Trolox相比，这三种化合物都具有较强的活性。大叶桃花心木素（1）的活性最强，50%抑制浓度（IC50）值为56μg mL(-1)。
