【摘要】 设计合成了 14个含不同性质取代基的黄烷酮类化合物 ,并采用核磁共振氢波谱、质谱和元素分析对所有化合物的结构进行了表征 .在系统测定化合物对水稻稻瘟病抑制活性的 IC5 0 值的基础上 ,采用H ansch- Fujita方法和 Co MFA方法对其定量结构活性关系进行了系统研究 ,结果发现 ,化合物的疏水性质、极化效应以及最高空轨道能级对杀菌活性有重要影响 ,化合物的疏水参数越小 ,分子越容易极化 ,则化合物的杀菌活性越高 .此外 ,最高空轨道能级越低 ,化合物越容易接受电子 ,其杀菌活性也相应提高 .通过考察∑ π、clg P以及 lg K与化合物杀菌活性的相关性 ,发现 lg K能较好地反映该类化合物的疏水效应 .三维定量构效关系研究表明 ,B环 2 ,3,4位上含有较大体积的取代基 ,而 6位含较小体积的取代基 ,有利于提高其杀菌活性 .更多还原

【Abstract】 Fourteen novel flavanone derivatives containing various substituents were designed and synthesized, whose structures were confirmed by 1H NMR, MS and elemental analysis. The fungicidal IC 50 in vitro against rice blast disease of the title compounds were tested and the quantitative relationship between their structures and fungicidal activities was analyzed by using comparative molecular field analysis({CoMFA}) and Hansch-Fujita approach. The results show that the hydrophobicity, polarity effect and the energy of the highest unoccupied orbital are very important for fungicidal activity. If the molecule was easy to polarize and had a lower LUMO energy, it would show a high fungicidal activity. Correlation results show that lgK is the most suitable parameter to describe the hydrophobicity of the title compounds compared to two other hydrophobic parameters, π and clgP. The results of 3D-QSAR analysis suggests that the introduction of steric bulk group onto the 2,3,4-position and small steric bulk onto the 6-position of B ring will be favorable to the activity of the compound. The CoMFA analyses about the electronic property requirement are consistent with those derived from the Hansch-Fujita approach.更多还原