决明属两种傣药中新颖的酚类化合物的发现及其抗病毒活性研究

Some plants of cassia genus are used as Chinses traditional herb medicines for a long time, and they closely relate to the daily living of the Dai nationality in Yunnan. In our previous works, the phytochemical study of Cassia siamea collected in Menghai area of Yunnan Province was carried out, and more than 30 new compounds (including four types of new skeleton for phenolic compounds, and two triterpenoids with unsual skeleton) were isolated from this plant. Some new phenolic compounds were found to be have notable antiviral activities. Take the genetic relationship between the plant of same genus for consider, it is possible to find the same type new compounds in the other plant of cassia genus. Based on this, 21 samples for three plants of cassia genus were collected by our group, and two samples with rich chemical components and notable antiviral activities were selected out by HPLC analysis and bioactives assay of their extract. In this project, the chemical constitutions of these two slected samples will be carefully studied by modern separation technology. As a result, more than thirty new compounds (incloding 2-3 compounds with new skeleton) were be isolated from these samples. The antiviral activities of the isolated compounds will be screened, and 3-5 compounds with notable antiviral activities will be selected out. These will provide the scientific basis for the utilization of Yunnan folk medicine, and the development of new medicines with self-contained intellectual property for our country. Furthermore, the antiviral mechanism for some compounds with high activities will be studied, and the mechanisms of antiviral activities, the relationships of phenolic structures and antiviral activities will also be discussed in this project.

一些决明属植物为云南民间常用的傣药，与傣族人民日常生活密切相关。我们前期从该属植物铁刀木中分离得到30多个新化合物，发现了4种酚类化合物新骨架和2个新颖度很高的新骨架三萜，并发现部分酚类化合物有明显的抗病毒活性。考虑到同属植物之间的亲缘关系，该属其它植物中也有存在新颖酚类化合物结构的可能。项目组进一步采集了该属3种植物21个样，通过HPLC分析和提取物活性筛从中精选出两个抗病毒活性相对突出、化学成分丰富的样品。本项目中将通过现代分离技术对这两个样品化学成分进行深入研究，并对化合物进行抗病毒活性筛选。预期从样品分离到30个以上的新颖酚类化合物，力争发现2-3个新骨架化合物并筛选出3-5个抗病毒活性突出的化合物结构，为合理开发利用云南民族药资源和开发我国自主知识产权的新药提供科学依据。项目还将选择部分活性好的化合物进行抗病毒机理和构效关系研究，揭示化合物的抗病毒活性机理和构效关系。

项目组在对决明属傣药铁刀木进行过前期研究的基础上，进一步采集了该属3种植物21个样，通过HPLC分析和提取物活性筛从中精选出两个抗病毒活性相对突出、化学成分丰富的样品进行深入研究。项目执行期内从铁刀木中分离到酚类化合物31个，发现新酚类化合物13个；还对傣药腊肠树和翅荚决明化学成分进行了深入研究；从腊肠树中分离到酚类化合物68个，发现新酚类化合物30个；从翅荚决明中分离到酚类化合物58个，发现新酚类化合物31个；这些新化合物结构类型包括：色酮、蒽醌、黄酮、酚类生物碱、香豆素、苯丙素、呋喃类、异香豆素等，其中6个化合物为项目组首次发现的新骨架类型。此外，项目组还对该属植物决明子和望江南化学成分进行了扩展性研究，从中发现了倍半萜类新化合物。项目组完成了决明属植物中分离到的168个酚类化合物(包含95个新化合物)的抗烟草花叶病毒活性筛选，发现10个化合物对花叶病毒的相对抑制率(%)超过对照宁南霉素。对活性最好的化合物9-(2-hydroxyethyl)-3,7-dimethyl- 1H-benzo[g] isochromen-1-one进行了抗病毒机理研究，证实作用机理为化合物能够诱导烟草叶片组织POD、PPO和PAL酶活性的提高，从而对病毒产生抗性。项目执行期内发表(含已校对)研究论文32篇，其中22篇为SCI收录期刊，申请发明专利9件(5件已获授权)，超额完成了计划任务书规定的任务。