长穗桑中的Diels-Alder型加合物

从长穗桑的茎皮中首次分离到9个Diels—Alder型加合物，通过NMR、MS等波谱分析手段分别鉴定为mulberrofuran K（1），mulberrofuran G（2），guangsangon L（3），kuwanon J（4），kuwanonx（5），guangsangonG（6），guangsangon B（7），guangsangon D（8），kuwanon P（9）。化合物1—9进行了抗氧化活性筛选。结果表明，在10^-5M浓度下，化合物1，2，5—7，9对Fe^2＋-半胱氨酸诱导的肝微粒体脂质过氧化产生的丙二醛（malondialdehyde，MDA）有抑制作用（抑制率大于50％）。

Diels-Alder Type Adducts from Morus wittiorum

Nine Diels-Alder type adduets have been isolated from the stem bark of Morus wittiorura for the first time. And on the basis of spectral analysis such as NMR,MS etc. ,structures of the compounds were identified as mulberrofuran K(1) ,mul-berrofuran G(2),guangsangon L(3),kuwanon J(4) ,kuwanon X(5),guangsangon G(6),guangsangon B(7),guangsangon D (8), kuwanon P(9). The anti-oxidative activity of compounds 1-9 were assayed. As a result ,compounds 1,2,5-7,9 showed in-hibition to malondialdehyde(MDA) produced during mierosomal lipid peroxidation induced by ferrous-eysteine (the inhibitory ratios were more than 50%) at a concentration of 10~(-5) M.