A procedure is presented for the prediction of physical property of organic compound and QSAR/QSPR analysis based on the similarity indices using a back-propagation neural network. The similarity indices were calculat...A procedure is presented for the prediction of physical property of organic compound and QSAR/QSPR analysis based on the similarity indices using a back-propagation neural network. The similarity indices were calculated on a chosen set of structural descriptors by equation 1 and used to quantify the similarity or dissimilarity of organic compound. The similarity indices were also used as an input parameter of neural network.The pκα. values of the 69 substituted phenols were predicted by using 32 compounds as a training set and all 69 compounds as a predicting set. The results obtained were satisfying.展开更多
文摘A procedure is presented for the prediction of physical property of organic compound and QSAR/QSPR analysis based on the similarity indices using a back-propagation neural network. The similarity indices were calculated on a chosen set of structural descriptors by equation 1 and used to quantify the similarity or dissimilarity of organic compound. The similarity indices were also used as an input parameter of neural network.The pκα. values of the 69 substituted phenols were predicted by using 32 compounds as a training set and all 69 compounds as a predicting set. The results obtained were satisfying.
文摘分子相似性是虚拟筛选技术的重要环节,在计算机辅助药物设计中有着关键作用。在2D Fingerprint相似性判别过程中,一些典型的分子相似性评估过程使用了Hash函数进行分子指纹映射,然而Hash函数固有的冲突问题极易降低分子指纹的映射精度。提出了一种基于计数型布隆过滤器的指纹映射方法,对相似性判别过程进行了有效改进,并采用DUD LIB VS 1.0数据集对改进方法进行了比较验证,将ROCE,AUC,awROCE,awAUC值作为评价标准。与其他原始分子相似性方法相比,所提方法有效地提高了相似性判断的准确性和骨架跃迁能力。
文摘组蛋白去乙酰化酶抑制剂(histone deacetylase inhibitor,HDACi)是近年来治疗癌症的重要靶向药物,其中羟氨酸类,苯甲酰胺类多种药物已进入临床试验阶段,但对于亲电酮类HDACi还有待于进一步研究,本研究应用比较分子力场分析法(comparative molecular field analysis,CoMFA),比较分子相似性指数法(compara-tive similarity indices analysis,CoMSIA)对29个亲电酮类HDAC抑制剂分子进行了定量构效关系分析,CoMFA模型的q2=0.668,r2=0.999;CoMSIA模型的q2=0.686,r2=0.995,所建模型预测能力较好。分子对接(sur-flex-dock)研究也进一步揭示出抑制剂分子与蛋白酶的作用模式,结合其作用模式比较合理地探讨了这类抑制剂的活性原因,为设计新型高效的亲电酮类HDACi提供了理论依据。
