新狼毒素B抑菌活性构效关系的进一步研究

Further study on relationship between structure and antibacterial activity of neochamaejasmine B

【目的】进一步研究新狼毒素B的抑菌活性构效关系。【方法】以新狼毒素B为原料,合成了7″-甲氧基（A2-1）、7,7″-二甲氧基（E3）和7,7,″4-三甲氧基（E1）3个新狼毒素B甲醚化产物及4-亚甲基新狼毒素B（D3）,利用ESI-MS1、H NMR和13C NMR对其结构进行了表征。选择金黄色葡萄球菌（S.aureas）、无乳链球菌（S.agalactiae）、大肠杆菌（E.coli）和沙门氏菌（Samonellal）为供试菌,采用药敏纸片法对新狼毒素B及其4种衍生物进行了抑菌活性测定。【结果】4种修饰物对所有供试菌的抑菌活性均小于新狼毒素B;3种甲醚化产物在质量浓度为0.625-5mg/mL时,对沙门氏菌没有抑菌活性;对于其他3种供试菌,各供试物的抑菌活性次序为新狼毒素B≈D3〉A2-1〉E3〉E1。【结论】新狼毒素B分子中,7-OH和7-″OH是其主要抑菌活性基团,4′-OH和4-OH对抑菌活性的贡献较小,4-羰基不是主要抑菌活性基团。

[Objective] It further studied the relationship between structure and antibacterial activity of neochamaejasmine B. [Method] Four compounds, 7″-methoxy neochamaejasmine B （A2-1）, 7,7″-dimethoxy neochamaejasmine B （E3）, 7,7″, 4′″-trimethoxy neochamaejasmine B （El） and 4-methylene neochamaejasmine B （D3） were prepared from neochamaejasmine B. Their structures were confirmed by ESI-MS, l H NMR and ^13C NMR. The antibacterial activity of neochamaejasmine B and its four derivatives were tested with dish diffusion of Neo-Sensitab in vitro against S. aureas, S. agalactiae, E. coli and Samonellal. [Result] The results showed that the antibacterial activity of four derivatives against all bacteria tested was lower than that of neochamaejasmine B. The antibacterial activity of A2-1 ,E3 and El against Samonellal disappeared at 0. 625-5 mg/mL. But the order of the antibacterial activity of all compounds against other bacteria was n-B≈D3〉A2-1〉E3〉E1. [Conclusion] The above mentioned structure-activity relationship studies showed that 7-OH and 7″-OH of neochamaejasmine B were the main active groups,and that 4′-OH and 4′″-OH had less contribution to its antibacterial activity,and that carbonyl group was not the main active group.