柿叶化学成分研究

Study on Chemical Constituents of the Leaves of Diospyros kaki

目的：研究柿叶中化学成分。方法：利用各种色谱方法对柿叶进行提取、分离和纯化,根据波谱数据分析及文献比对鉴定化合物结构,并经体外活性筛选,考察化合物清除DPPH和ABTS能力。结果：从柿叶中分离得到12个单体化合物,分别鉴定为：2-（（R）-1-羟乙基）-3-甲基马来酰亚胺（1）、2-（2-羟乙基）-3-甲基马来酰亚胺（2）、羟基酪醇（3）、原儿茶醛（4）、原儿茶酸（5）、C-藜芦酰乙二醇（6）、3-（4-羟基-3-甲氧苯基）-1,2-丙二醇（7）、乙酰对羟基苯乙醇（8）、4-羟基-3-甲氧基苯甲酸（9）、2,4-二羟基-6-甲基苯乙酮（10）、香豆酸甲酯（11）、4-烯丙基儿茶酚（12）。化合物3、5、7、12对DPPH和ABTS的清除率的IC50分别为0.7-36.0和3.6-6.1μg/mL。结论：其中,化合物1为新构型化合物,化合物1、2、6-8、10为首次从该属植物中分离得到,化合物1-3、6-8、10-12为首次从该植物中分离得到。药理活性结果表明化合物3、5、7、12具有较强的抗氧化活性。

Objective：To study the chemical constituents of Diospyros kaki leaves. Methods：The compounds were isolated and puri- fied from Diospyros kaki leaves by various column chromatographic techniques. Their chemical structures were elucidated on the basis of spectroscopic data analysis and physicochemical properties. The antioxidant activity of the twelve compounds were determined by using DPPH and ABTS free radical scavenging method, and Trolox was used as a positive control drug. Results：Twelve compounds were isola- ted and identified as 2- （ （ R ） 1 -hydroxyethyl ） -3 -methyl maleimide （ 1 ）, 2 - （ 2 -hydroxyethyl ） -3-methyl maleimide （ 2 ）, hydroxytyrosol （ 3 ）, protocatechualdehyde （4）, protocatechuic acid （ 5 ）, C-veratroylglycol （ 6 ）, 3- （4-hydroxyl-3-methoxyphenyl） propane-I, 2-diol （ 7 ）, 2-（ 4＇-hydroxyphenyl ） ethyl acetate （ 8 ）, 4-hydroxyl-3-methoxybenzoic acid （ 9 ）, 2,4-dihydroxy-6-methylacetophenone （ 10 ）, methyl Pcoumarate （ 11 ） ,4-allylpyrocatechol （ 12）, the ICso of compounds 3,5,7 and 12 removing DPPH and ABTS were 0. 7 - 36. 0,3.6 - 6. 1 μg/mL. Conclusion：Compound 1 is a compound with new structure, compounds 1,2,6 -8, and 10 are obtained from this genus for the first time, and compounds 1 - 3,6 - 8,10 - 12 are isolated from this plant for the first time. The rate of compounds 3,5,7, and 12 removing DPPH and ABTS indicate that these four compounds have strong antioxidant activity,respectively.