【作者】 曹秀芳；

【导师】 刘盛华；

【作者基本信息】 华中师范大学 ， 有机化学， 2009， 博士

【摘要】 社会的发展和人们环保意识的增强,对农药的创制提出了越来越高的要求,即创制的农药新品种要达到高活性、低毒性、低残留、环境相容性好等。在现代农药研究中,手性农药由于具有活性高、用量低、环境影响小等特点以及受管理因素、知识产权因素、市场因素和效益因素的影响,其研究与应用受到了越来越多的重视。在手性农药研究中,含氮杂环的手性三唑类杀菌剂一直备受国内外农药研究者的关注。因此,本文拟将手性诱导的不对称合成技术应用于具有潜在生物活性的新型手性三唑衍生物的合成之中,期望通过手性含氮杂环三唑类有机化合物的合理设计、合成及生物活性的系统研究,发现部分具有较好生物活性的手性先导分子,为进一步的结构优化及新药发现提供一定的研究思路及基础数据。本文共设计合成了60个未见文献报道的新型手性三唑类化合物,并研究了所合成化合物的生物活性、结构-活性关系及波谱性质等,发现了一些潜在的高活性手性杀菌剂,其具体研究内容如下:1.以樟脑磺内酰胺为手性辅剂,实现了格氏试剂对α,β-不饱和羰基化合物的高区域选择性和高立体选择性共轭加成。在此过程中详细探讨了该反应的反应规律,扩大了其在不对称合成中的应用,高立体选择性（de值高达99%）地合成了一系列重要中间体。对所有未见文献报道的中间体都进行了结构表征,部分代表性化合物还经过单晶X-射线衍射分析确证了其结构。同时,通过此方法获得了高对映选择性的手性酮、手性醇等重要的合成切块及药物中间体。2.应用手性辅剂樟脑磺内酰胺的手性诱导作用,高对映选择性地合成了一系列β-芳基取代手性酮,其ee值高达99%,可用于药物及其它精细化工中间体的不对称合成。3.应用手性辅剂樟脑磺内酰胺的手性诱导作用,设计合成了一系列光学纯的γ-芳基-1H-1,2,4-三唑类衍生物,所有目标化合物都采用了¹H NMR、¹³C NMR、MS和元素分析进行了结构表征,同时也获得了部分代表性化合物的晶体结构,进一步确证了化合物的结构。并对所有目标化合物进行了生物活性测定,发现了一批具有优良杀菌活性的化合物。4.以细胞色素P450（PdCYP51）为靶标,利用结合光谱法对合成的LSH1和LSH2两个系列共90个化合物进行了结合光谱测定,结合生物测定的结果筛选出了一批结合能力强和杀菌效果好的新型抗真菌化合物。实验结果表明,与商品化杀菌剂相比,其中有20个化合物抑制活性比三唑酮好,EC₅₀＜2.27 mg/L;有19个化合物抑制活性比三唑醇好,EC₅₀＜1.44 mg/L;有4个化合物抑制活性比戊唑醇好,EC₅₀＜0.37 mg/L。总体来说,LSH2系列化合物的活性比LSH1系列化合物好,LSH2系列化合物与靶标酶PdCYP51结合紧密,结合常数K_d值在0.003～0.446μM间,体现出了进一步研究的价值。同时,在对柑橘绿霉菌EC₅₀测定过程中,进一步发现有9对化合物,其R和S构型的生物活性差异较大,其中差别最大的是化合物LSH1019与LSH1020,相差230倍。通过对部分LSH1系列化合物与玉米黑粉菌CYP51的结合常数测定,表明所测的化合物都能与玉米黑粉菌CYP51结合。更多还原

【Abstract】 The development of the society and the enhancement of national awareness of environment protection have put forward higher and higher requirements to the research and development of pesticide,namely the novel agrochemicals must achieve the features of high activity,low toxicity,low residue,and better environment compatibility.During the course of the research on the modern pesticide,the studies and applications of chiral pesticides have drawn more and more attentions because the effect factors of high activity,low dose,low environmental impact,management, intellectual property,market and efficiency.Chiral azaheterocycle triazole derivatives have been paid close attention to by all the world in the research of chiral pesticides.Therefore,we report our efforts in designing and synthesis of novel chiralγ-aryl-1H-1,2,4-triazole derivatives by using chiral induction method,and we expect to find high-activity lead compound through the systematic research of rational design,synthesis and bioactivity of chiral triazoles derivatives.Sixty novel chiral triazole derivatives were designed and synthesized based on chiral induction asymmetric synthesis,which have not been reported in the literature.Their bioactivities,structure-activity relationships and spectral properties were evaluated and some of the compounds exhibited good biological properties,which might be developed as potential lead compounds for further optimization.The research contents are as follows:1.This text takes Oppolzer’s sultam as chiral auxiliary,and realized the asymmetric conjugate addition of Grignard reagents to aryl substitutedα,β-unsaturated carbonyl compounds with great regioselectivities and excellent diastereoselectivities.Through systematic detailed studies and discussions about the reaction rules of this novel approach,whose application in asymmetric synthesis has been expanded.A series of important intermediates were synthesized with high diastereoselectivities（de up to 99%）.All these compounds were well structurally characterized by spectral methods,and some representative compounds have been elucidated by X-ray diffraction analysis.Moreover,many important building blocks and medicinal intermediates such as chiral ketones,alcohols can be conveniently obtained with excellent enantioselectivies.2.Whereafter,we achieved a highly enantioselective approach towards the synthesis ofβ-substituted chiral ketones utilizing Oppolzer’s sultam as chiral auxiliary.The（R）-and（S）-enantiomer of target chiral ketones were obtained with up to 99%ee.This could be a fascinating method for the practical syntheses of chiral synthons as valuable building blocks and important medicinal intermediates.3.Series of novel optical pureγ-aryl-1H-1,2,4-triazole derivatives were designed and synthesized by using the chiral auxiliary（Oppolzer’s sultam）,and all these target compounds were structurally characterized by ¹H NMR,¹³C NMR,MS and elemental analysis,at the same time,some representative compounds have been elucidated by X-ray diffraction analysis.On the other hand,the preliminary bioassay results indicated that some of chiralγ-aryl-1H-1,2,4-triazole derivatives exhibited superior fungicidal activity.4.In this study,we evaluate the inhibition activity of chiral triazole derivatives LSH1 and LSH2 targeting cytochrome P450（PdCYP51）using binding spectrum method,and a batch of novel antifungal compounds with high binding ability and excellent fungicidal activity were screened out. The preliminary test results indicate that twenty compounds exhibit better inhibition activity compared with the commercially avilable fungicides triadimefon(EC₅₀＜2.27 mg/L),and nineteen compounds have better activity than that of triadimenol(EC₅₀＜1.44 mg/L),as well as four compounds are better than tebuconazole(EC₅₀＜0.37 mg/L).Generally speaking,the activities of LSH2 are better than LSH1,and the compounds of LSH2 have the stronger binding ability with target enzyme PdCYP51 than other compounds,and the binding constants Kd are in the range of 0.003～0.446μM, which are worthy to be futher investigated.During the course of test for EC₅₀of P.digitatum,we find that there are nine pairs of target compounds,the enantiomers（R and S）of which embody significant activity differences.The most exiting outcome is the huge difference in biological activity between compounds LSH1019 and LSH1020,and the activity of LSH1019 is about 230-fold more than that of LSH 1020.Furthermore,the binding activity tests with Ustilago maydis CYP51 for compounds LSH1 are also determined,and the results indicate that all the tested compounds can bind with Ustilago maydis CYP51.更多还原