Our work shows that differdnt compound orientations have different results in Comparative Molecular Field Analysis(CoMFA).For three analyzed compound series,the squared correlation coefficients of cross-validation(q2)...Our work shows that differdnt compound orientations have different results in Comparative Molecular Field Analysis(CoMFA).For three analyzed compound series,the squared correlation coefficients of cross-validation(q2)could vary as largely as 0.30~0.40 among all possible orientations.THe reason for this comes from the routine adopted by CoMFA which uses discrete,regularly arrayed grids to represent the molecular field.Therefore,different orientatins may map their molecular fields differently onto the grid and accordingly give different results from partial least square(PLS)analyses.We have developed a method all-orientation searching,to seek for the orientation with the best CoMFA result. And ,we suggest that all-orietnation searching shoule be incorporated intto the standard CoMFA procedurd.展开更多
采用比较分子场分析(comparative molecular field analysis,CoMFA)和比较分子相似性指数分析(comparative similarity indices analysis,CoMSIA)方法,分别对一系列新烟碱类杀虫剂及相关化合物烟碱乙酰胆碱受体激动剂进行了结构与活性...采用比较分子场分析(comparative molecular field analysis,CoMFA)和比较分子相似性指数分析(comparative similarity indices analysis,CoMSIA)方法,分别对一系列新烟碱类杀虫剂及相关化合物烟碱乙酰胆碱受体激动剂进行了结构与活性关系的研究,构建了CoMFA及CoMSIA模型;该模型具有较好的预报能力和拟合能力,CoMFA:q2=0.563,r2=0.950;CoMSIA:q2=0.657,r2=0.973.通过三维等势图分析得出了对新烟碱类活性影响较大的基团或原子,为新烟碱类化合物的进一步研究提供了依据.展开更多
采用基于R基团搜索技术的Topomer Co MFA技术对一系列喹诺酮羧酸类衍生物进行三维定量构效(3D-QSAR)关系研究,所得模型结果的交叉验证相关系数(q2)为0.790,非交互验证系数(r2)为0.890,外部验证的复相关系数(r2pred)为0.878,研究结果表...采用基于R基团搜索技术的Topomer Co MFA技术对一系列喹诺酮羧酸类衍生物进行三维定量构效(3D-QSAR)关系研究,所得模型结果的交叉验证相关系数(q2)为0.790,非交互验证系数(r2)为0.890,外部验证的复相关系数(r2pred)为0.878,研究结果表明该模型具有良好的稳定性和预测能力。采用Topomer search技术在ZINC数据库中进行虚拟筛选,筛选出6个Ra基团和3个Rb基团,进而设计出12个具有更高活性的新型喹诺酮羧酸类化合物。采用分子对接技术对药物与受体的作用机制进行了研究,结果显示,药物与蛋白酶的ASP 30、ASP 29和ASN 25位点作用明显,该QSAR的研究结果可为新药合成提供理论参考。展开更多
文摘Our work shows that differdnt compound orientations have different results in Comparative Molecular Field Analysis(CoMFA).For three analyzed compound series,the squared correlation coefficients of cross-validation(q2)could vary as largely as 0.30~0.40 among all possible orientations.THe reason for this comes from the routine adopted by CoMFA which uses discrete,regularly arrayed grids to represent the molecular field.Therefore,different orientatins may map their molecular fields differently onto the grid and accordingly give different results from partial least square(PLS)analyses.We have developed a method all-orientation searching,to seek for the orientation with the best CoMFA result. And ,we suggest that all-orietnation searching shoule be incorporated intto the standard CoMFA procedurd.
文摘采用比较分子场分析(comparative molecular field analysis,CoMFA)和比较分子相似性指数分析(comparative similarity indices analysis,CoMSIA)方法,分别对一系列新烟碱类杀虫剂及相关化合物烟碱乙酰胆碱受体激动剂进行了结构与活性关系的研究,构建了CoMFA及CoMSIA模型;该模型具有较好的预报能力和拟合能力,CoMFA:q2=0.563,r2=0.950;CoMSIA:q2=0.657,r2=0.973.通过三维等势图分析得出了对新烟碱类活性影响较大的基团或原子,为新烟碱类化合物的进一步研究提供了依据.