多环聚异戊烯基酰基间苯三酚类化合物(PPAPs)结构新颖多样，是近期抗肿瘤创新药物研发的热点先导化合物。核受体RXRα是抗肿瘤药物研究的一个理想的分子靶点。我们前期从元宝草中发现了部分具有RXRα转录抑制活性及肿瘤细胞毒活性的PPAPs，提示该类成分可能通过RXRα通路诱导肿瘤细胞凋亡，由于得到的化合物数量有限，其作用机制及构效关系尚无法明确，而有关PPAPs作为RXRα介导肿瘤细胞凋亡的天然小分子调节剂的研究，也未见系统研究报道。因此，本课题以福建挺茎遍地金中复杂笼状的PPAPs为研究对象，采用化学筛选与活性筛选相结合的研究模式，定向分离和富集PPAPs类成分并对结构新颖的PPAPs的生物合成途径进行合理的推测；通过RXRα双报告基因及多种生物学手段，研究活性化合物的作用机制并探讨构效关系。通过上述研究工作，将为进一步开展PPAPs的结构修饰和和发现靶向RXRα的新型抗肿瘤药物奠定基础。

Polycyclic Polyprenylated AcylPhloroglucinols (PPAPs) is an important source of innovative antitumor drugs with novel structures. RXRa has been an ideal drug target for therapeutic applications, especially in the treatment of cancer. In our preliminary study, several PPAPs have been found to show potential RXRα transcriptional-inhibitory activities and cytotoxicity against HeLa cells, which indicated that PPAPs may induce tumor cell apoptosis via RXRα pathways. However, its mechanism of action and structure-activity relationship is still unclear due to the limited number of obtained compounds. Besides, there is no systematic research on PPAPs as natural micromolecule regulators of RXRα mediated tumor cell apoptosis. Thus, our study focus on the complex caged PPAPs in Hypericum elodeoides Choisy using the chemical and activity combined screening method to directly isolate and enrich the PPAPs as well as propose the possible biosynthetic pathways of novel PPAPs, study the mechanism of the active compounds by RXRα reporter gene and various biological assays as well as discuss the structure-activity relationship. The above research contents will lay foundation for further development of structure modification and creation of new type antitumor drugs targeted RXRα.