2,4,5-三苯基咪唑类化合物的合成及其双光子特性

以4,4′-二甲基苯偶酰为原料合成了3个2-(4-取代苯基)-4,5-二(4-甲基苯基)咪唑系列衍生物,对其结构进行了表征,通过测定其光物理性质,发现这类化合物不仅具有较高的荧光量子产率,而且具有较大的双光子吸收截面,是很好的双光子显微和成像以及上转换激射荧光的候选材料.     

Support vector machine applied in QSAR modelling

Support vector machine （SVM）, partial least squares （PLS）, and Back-Propagation artificial neural network （ANN） were employed to establish QSAR models of 2 dipeptide datasets. In order to validate predictive capabilities on external dataset of the resulting models, both internal and external validations were performed. The division of dataset into both training and test sets was carried out by D-optimal design. The results showed that support vector machine （SVM） behaved well in both calibration and prediction. For the dataset of 48 bitter tasting dipeptides （BTD）, the results obtained by support vector regression （SVR） were superior to that by PLS in both calibration and prediction. When compared with BP artificial neural network, SVR showed less calibration power but more predictive capability. For the dataset of angiotensin-converting enzyme （ACE） inhibitors, the results obtained by support vector machine （SVM） regression were equivalent to those by PLS and BP artificial neural network. In both datasets, SVR using linear kernel function behaved well as that using radial basis kernel function. The results showed that there is wide prospect for the application of support vector machine （SVM） into QSAR modeling.     

2-苯基吲哚衍生物的定量结构-活性关系研究

 应用半经验量子化学AM1法得到了36种2-苯基吲哚衍生物的优势构像,再利用量子化学算法和分子图形学技术获得电子结构、几何结构及连接性结构参数,并将这些参数和2-苯基吲哚衍生物在4℃时与小牛子宫雌激素受体的相对亲合力相关联.结果表明:2-苯基吲哚衍生物在4℃时与小牛子宫雌激素受体的亲合力大小和氮原子所连原子的净电荷Q;2号、3号、10号和15号原子间的二面角D;5号碳原子与其所连原子间的键长L和零阶连接性指数°G的相关性较好,成功地建立了36种2-苯基吲哚衍生物的构效关系式.     

抗爱滋病药物吡喃酮类化合物电子结构与生物活性关系

吡喃酮类化合物是抗爱滋病的一种新药，用从头计算法G98W程序对19个吡喃酮类化合物进行量子化学计算，讨论它们的电子结构特征与生物活性的关系，得到较满意的结果，可为这类抗爱滋病化合物的分子设计提供参考依据。     

Chemistry of odor stimuli

Summary The present state of the molecular basis of olfaction is shown. With the aid of various examples the regioselectivity of odor sensation is proven. The main part of the experimentation concerns the stereocontrolled process of odor release.     

9-Methyl-7-bromoeudistomin D,a potent inducer of calcium release from sarcoplasmic reticulum of skeletal muscle

Summary The Ca²⁺-releasing action of several derivatives of eudistomin D isolated from a marine tunicate was compared with that of caffeine. It was found that 9-methyl-7-bromoeudistomin D was approximately 1000 times more potent than caffeine in causing Ca²⁺ release from the sarcoplasmic reticulum.The authors thank Ms A. Muroyama of this institute for her technical assistance and Prof. K. L. Rinehart of University of Illinois for his encouragement.     

分子连接性指数计算机算法

针对目前定量构效关系研究中应用较多的分子连接性指数(MCI)进行了研究。为提高MCI计算的效果及实用性,对MCI的计算方法进行了详尽的分析,并完成MCI计算软件的编写、调试工作,实现了不同结构分子的计算机识别及MCI计算通用化。此外,通过建立点价距离矩阵,简化了传统MCI的计算方法,使MCI的计算具有效率高、不易出错等优点,便于MCI计算程序化。     

取代苯胺、苯酚对鲤鱼毒性的定量构效关系

测定了16种取代苯胺,苯酚化合物对鲤鱼96h的急性毒性,了中毒症状,根据受体学说,进行定量构效关系（QSAR）研究,建立了QSAR方程,结果表明,分配过程及有机物分子与细胞内分子间的上互作用是影响这两类化合物生物毒性的主要因素。     

生姜乙醇提取物色谱保留的拓扑研究

基于Kier连接性指数(mXvt)建立Kier逆指数(mFwt),使用最佳变量子集回归构建了生姜乙醇提取物中22种化学成分的气相色谱保留时间(Tm)的三元数学模型,其传统相关系数(R2)为0.978,它的计算值与相应实验值基本吻合.经变异膨胀因子(VIF)分析,该模型具有高度稳健性.结果表明,Kier逆指数对有机物气相...