含苯并咪唑的杨梅素衍生物合成及生物活性研究

【作者】 陈梅；

【导师】 薛伟；

【作者基本信息】 贵州大学 ， 有机化学， 2021， 硕士

【摘要】 杨梅素类化合物,作为一种重要的黄酮衍生物,具有抑菌、抗病毒、抗肿瘤、降血糖和抗炎等多种生物活性,近年来人们研究发现此类化合物具有明显的抑菌和抗病毒活性,同时,苯并咪唑是一种重要的杂环类化合物,具有优良的杀菌活性外还具有抗病毒和抗肿瘤等多种生物活性,目前已有部分含苯并咪唑的衍生物用于临床治疗,本文利用活性拼接原理,将苯并咪唑小分子引入到杨梅素结构中,合成了42个含苯并咪唑的杨梅素衍生物,化合物通过¹H NMR,¹³C NMR,¹⁹F NMR以及HRMS进行表征。并对所合成的化合物进行了抑制植物病原菌和抗病毒活性测试,同时通过单晶衍射仪确定了化合物4g和6n的晶体结构,以进一步确证系列化合物的结构。采用浊度法对所合成的化合物进行抑菌活性测试,以商品药剂噻菌铜和叶枯唑为对照。实验结果表明:化合物4l、4o、4t、6a、6i和6k对柑橘溃疡病菌（Xac）的EC₅₀值分别为14.4、19.1、21.3、27.8、24.2和20.0μg/m L,优于对照药剂噻菌铜（69.5μg/m L）和叶枯唑（89.5μg/m L）。化合物4l、4p、4u、6a、6d和6e对烟草青枯病菌（Rs）的EC₅₀值分别为10.5、18.1、11.5、22.0、21.7和14.5μg/m L,优于对照药剂噻菌铜（118.9μg/m L）和叶枯唑（55.1μg/m L）。化合物4k、4l、4m、4q、6d、6i和6r对水稻白叶枯病菌（Xoo）的EC₅₀值分别为14.0、17.2、17.2、8.2、20.4、24.9和36.1μg/m L,优于对照药剂噻菌铜（83.1μg/m L）和叶枯唑（60.1μg/m L）。同时,采用剪切叶片对比法,对目标化合物4q进行了水稻白叶枯病菌的活体实验,结果表明:在治疗活性方面,化合物4q的防治效果为（45.2%）,优于对照药剂噻菌铜（30.5%）和叶枯唑（34.8%）,在保护活性方面,化合物4q的防治效果为（48.6%）,优于对照药剂噻菌铜（35.7%）和叶枯唑（41.8%）。扫描电镜实验表明,化合物4q对水稻白叶枯病菌的抑菌作用导致细菌的细胞膜出现褶皱、破损。采用半叶枯斑法对所合成的化合物进行抗烟草花叶病毒（TMV）的治疗、保护和钝化活性测试,以商品药剂宁南霉素为对照,在浓度为500μg/m L条件下,化合物6n对TMV有较好的治疗活性,相应的抑制率为54.1%,优于宁南霉素（49.0%）。此外,化合物6j和6n对TMV表现出显着的保护作用,相应的抑制率分别为61.5和57.6%,优于宁南霉素（55.8%）。微量热泳动（MST）实验表明,化合物6n与TMV外壳蛋白（TMV-CP）结合的K_d值为1.049±0.582μmol/L,优于先导化合物杨梅素（67.269±27.940μmol/L）和对照药剂宁南霉素（1.058±0.285μmol/L）,说明化合物6n与TMV-CP之间有较强的相互作用。更多还原

【Abstract】 Myricetin compounds,as an important flavonoid derivative,have a variety of biological activities such as antibacterial,antiviral,antitumor,anti-glycemic and anti-inflammatory.In recent years,studies have found that such compounds have obvious antibacterial and antiviral activity.At the same time,benzimidazole is an important heterocyclic compound,which has excellent bactericidal activity and also has various biological activities such as antiviral and antitumor.At present,some derivatives containing benzimidazole have been used for clinical treatment,this article uses the principle of active splicing to introduce benzimidazole into the myricetin structure,and synthesize 42 myricetin derivatives containing benzimidazole.Compounds are processed by ¹H NMR,¹³C NMR,¹⁹F NMR and HRMS characterization.The compounds were tested for their anti-plant pathogens and antiviral activity.At the same time,the crystal structures of compounds 4g and 6n were determined by a single crystal diffractometer to further confirm the structure of the series of compounds.The antibacterial activities of the target compounds against plant pathogens were tested in vitro by the turbidimeter test.The commercial bactericides thiodiazole copper（TC）and bismerthiazol（BT）were chosen as control.The experimental results showed that the EC₅₀values of compounds 4l,4o,4t,6a,6i and 6k against Xanthomonas axonopodis pv.citri（Xac）were 14.4,19.1,21.3,27.8,24.2 and 20.0μg/m L,respectively,which were better than the control TC（69.5μg/m L）and BT（89.5μg/m L）.The EC₅₀values of compounds 4l,4p,4u,6a,6d and 6e against Ralstonia solanacearum（Rs）were 10.5,18.1,11.5,22.0,21.7 and 14.5μg/m L,respectively,which is better than the control TC（118.9μg/m L）and BT（55.1μg/m L）.The EC₅₀values of compounds 4k,4l,4m,4q,6d,6i and 6r on Xanthomonas oryzae pv.oryzae（Xoo）were 14.0,17.2,17.2,8.2,20.4,24.9 and 36.1μg/m L,respectively,which were better than the control TC（83.1μg/m L）and BT（60.1μg/m L）.At the same time,the target compound 4q was subjected to in vivo experiments on Xoo using the shearing leaf comparison method.The results showed that in terms of curative activity,the control effect of compound 4q was（45.2%）,which was better than the control TC（30.5%）and BT（34.8%）.In terms of protective activity,the control effect of compound 4q was（48.6%）,which was better than the control TC（35.7%）and BT（41.8%）.Scanning electron microscopy experiments showed that the antibacterial effect of compound 4q on Xoo caused the bacterial cell membrane to wrinkle and break.The curative,protective and inactivation activities against tobacco mosaic virus（TMV）in vivo at 500μg/m L were assessed by the half leaf blight spot method.The commercial agent ningnanmycin was used as control.Compound 6n have a better curative activity on TMV,with corresponding inhibition rate is 54.1%,which was better than ningnanmycin（49.0%）.In addtion,compounds 6j and 6n exhibited signifcant protective effects against TMV,with corresponding inhibitory rates of 61.5and 57.6%,respectively,which were superior to that of ningnanmycin（55.8%）.Microscale thermophoresis（MST）also showed that the binding of compound 6n to TMV coat protein（TMV-CP）gave a K_dvalue of 1.049±0.582μmol/L,which was superior to the lead compound myricetin（67.269±27.940μmol/L）and the control agent ningnanmycin（1.058±0.285μmol/L）,It shows that there is a strong interaction between compound 6n to TMV-CP.更多还原