The electronic structures of QHS and DQHS were completely optimized and calculated by B3LYP density functional theory at the 6-31g* level. The relationship between electronic structure parameters and antimalarial acti...The electronic structures of QHS and DQHS were completely optimized and calculated by B3LYP density functional theory at the 6-31g* level. The relationship between electronic structure parameters and antimalarial activity was discussed. There exists significant difference in frontier orbitals of QHS and DQHS. Their net charges and bond orders were also compared respectively. The results of calculation prove theoretically that the endoperoxy bridge is the essential of antimalarial activity. The difference of antimalarial activity between QHS and DQHS was reasonably explained based on their electronic structures.展开更多
The structure-activity relationship study of C-10 substituted artemisinin (QHS) derivatives that are used as antimalarial was performed with the RS (rough sets) method. An RS process is a concise nonlinear process, an...The structure-activity relationship study of C-10 substituted artemisinin (QHS) derivatives that are used as antimalarial was performed with the RS (rough sets) method. An RS process is a concise nonlinear process, and it has broad application foreground in the data mining of nonlinear life courses. In this work, initially the parameters of C-10 substituted QHS’s derivatives were computed with the quantum chemistry method, and the information table was constructed from the parameters (condition attributes) and biological activity (decision attributes). Based on the analysis of rough set theory, the core and reduction of attributes sets were obtained. Then the decision rules were extracted and the struc-ture-activity relationship was analyzed. As a nonlinear system, RS theory can extract the special rela-tion in the database. It has the advantage of being nonlinear over multiple linear regression (MLR), principal component analysis (PCA), partial least square (PLS), etc., and the advantage of obtaining results with unambiguous physical meanings over artificial neuron networks (ANNs), etc. The result obtained in this study is instructive to the study of pharmacodynamics, resistance mechanism of QHS and development of QHS’s derivatives.展开更多
文摘The electronic structures of QHS and DQHS were completely optimized and calculated by B3LYP density functional theory at the 6-31g* level. The relationship between electronic structure parameters and antimalarial activity was discussed. There exists significant difference in frontier orbitals of QHS and DQHS. Their net charges and bond orders were also compared respectively. The results of calculation prove theoretically that the endoperoxy bridge is the essential of antimalarial activity. The difference of antimalarial activity between QHS and DQHS was reasonably explained based on their electronic structures.
文摘The structure-activity relationship study of C-10 substituted artemisinin (QHS) derivatives that are used as antimalarial was performed with the RS (rough sets) method. An RS process is a concise nonlinear process, and it has broad application foreground in the data mining of nonlinear life courses. In this work, initially the parameters of C-10 substituted QHS’s derivatives were computed with the quantum chemistry method, and the information table was constructed from the parameters (condition attributes) and biological activity (decision attributes). Based on the analysis of rough set theory, the core and reduction of attributes sets were obtained. Then the decision rules were extracted and the struc-ture-activity relationship was analyzed. As a nonlinear system, RS theory can extract the special rela-tion in the database. It has the advantage of being nonlinear over multiple linear regression (MLR), principal component analysis (PCA), partial least square (PLS), etc., and the advantage of obtaining results with unambiguous physical meanings over artificial neuron networks (ANNs), etc. The result obtained in this study is instructive to the study of pharmacodynamics, resistance mechanism of QHS and development of QHS’s derivatives.
