Part Of A Nature / Organic Quantitative Structure Activity Relationship Studies,

Quantitative Structure-Property/Activity Relationships has become of interest area in recent years, which is covered with the Chemistry and the Biological Science. There are 100,000 kinds of chemicals introduced into the environments according to the American Chemical Abstract. Cost and time limitations will not allow us to test their toxicities and assess their fates one by one. Therefore, there is a need to develop procedures which can rapidly screen chemicals for their toxicological properties and allow us to focus scarce resource on chemicals with the greatest potential risk. QSAR models based on parameters that can be calculated for any arbitrary chemical structure are gradually emerging as the method of choice.The main research chemicals of this thesis are including the common organic pollutants like polychlorinated organic compounds (PCOCs), and intermediates like benzanilides, benzaledhydes, indole and their derivatives to synthesize medicines, dyes and pesticides. Physico-chemical properties and biological activities were determined for the above compounds, including octanol/water partition coefficients, water solubility, acute toxicity to Photobacterium phosphoreum for indole derivates and toxicity to Daphnia magna for benzanilides, the HPLC capacity factors of substituted indoles and substituted benzaledhydes. The obtained data contributed to research of the environmental behaviors of the compounds and provided basis for their ecological risk assessment. Several QSAR methods were studied and some QSAR models with clear chemical sense were developed for the kinds of compounds. Mechanisms determining changes in properties and the structure descriptors of the compounds were explored by analyzing relationships between the properties and the structure descriptors of the compounds. The quantitative structure-activity relationship methods and structure descriptors included in this thesis are Hansch method, linear solvation energy relationship (LSER), quantum chemical parameters, topological indices such as molecular connectivity indices and edge-adjacency index. Comprehensive methods were syncretized to make the QSAR equations more theoretically rational and applicable. The thesis included four parts: introduction; quantitative structure-property relationship; quantitative structure-activity relationship; quantitative structure-retention relationship.