熊果酸衍生物的合成与表征及其抑菌活性研究

熊果酸属于五环三萜类配合物,在自然界中分布广泛,并显示出多种生物活性,如保肝、抗炎、抗病毒、抗癌等多种药理作用.为寻找高效、低毒的熊果酸衍生物,以具有一定生物活性的熊果酸为先导配合物,通过对其C-28位进行结构修饰及C-3位引入氨基酸,共设计合成了10种未见报道的熊果酸衍生物.目标配合物的结构经1 H NMR、IR和HRMS表征确证,并以其对培养于高铁血红蛋白的金黄色葡萄球菌、耐甲氧西林金黄色葡萄球菌、耐喹诺酮金黄色葡萄球菌和培养于脑心浸液培养基中的大肠杆菌进行抑菌活性测试.结果表明,经修饰后的熊果酸衍生物对金黄色葡萄球菌、耐甲氧西林金黄色葡萄球菌、耐喹诺酮金黄色葡萄球菌的抗菌活性较母体配合物有不同程度的提升.

Synthesis and characterization of ursolic acid derivatives,and the study on the antibacterial activity

Ursolic acid belongs to pentacyclic triterpenoid of natural products. It widely distributed in nature and showed many bioactivities such as hepatoprotective, anti-inflammatory, anti-cancer activi- ty, antiviral pharmacological. In order to develop novel ursolic acid derivatives with high efficiency, low toxicity, we take the natural product ursolic acid which with biological activity as the lead com- pound for modifying their structures. In this paper, ten novel ursolic acid derivatives were designed and synthesized through modification at C-28 of ursolic acid and introducing amino acid at C-3. Struc- tures of all target compounds were confirmed by ~H NMR, IR and HRMS. These compounds were tested antibacterial activity, which were Staphylococcus aureus, Methicillin-resistant staphylococcus aureus, Quinolone staphylococcus aureus cultured on MHB and E. coli were cultured on BHI. The results showed that their anti-bacterial activities for Staphylococcus aureus, Methicillin-resistant staphylococcus aureus, Quinolone-resistant staphylococcus aureus were improved compared to ursolic acid.