Thiourea Synthesis, Characterization And Quantitative Structure-activity Relationship (qsar) Study

Thiourea compounds have excellent anti-bacterial nature and favorable bioactivity. It is worth studying on the relationship between the molecular structure of these compounds and their biological activities. The research methods of basing on structure-activity relationship of these compounds are founded, which made the synthesis of this kind of compounds have definite purpose and direction, the development cost of these thiourea anti-bacterial can be greatly reduced. Therefore, This research has important theoretical significance and application value.This thesis comprises two parts:1) synthesis, characterization and properties of thiourea compounds; 2) structure-activity relationship (QSAR) of thiourea compoundsThe first part, four new thiourea compounds. show below:4,4'-bis(3-N-Methoxyformyl thioureido)-diphenylmethane4,4'-bis(3-N-Ethoxyformyl thioureido)-diphenylmethane4,4'-bis(3-N-Benzoyl thioureido)-diphenylmethane4,4'-bis(3-N-p-Methxoylbenzoyl thioureido)-diphenylmethaneAll these compounds were characterized by IR, Elemental analysis, and'HNMR. The specific heat capacity of the aforementioned four compounds were determined using continuous Cp mode, with a Micro-DSCⅢmicro-heat instrument at 298.5 K. The enthalpy, entropy and Gibbs free energy of compounds were calculated for temperatures between 283 K and 353 K. relative to the standard temperature 298.5K. The DSC, TG/DTG methods were used to study the thermal behaviors of the above four compounds. Quantum chemical study on the above two compounds with Gaussian 03W package.The second part:The data bioactivity of 44 thiourea compounds synthesized by our research group were collated; The geometries and enthalpy of formation of these compounds were fully optimized with the Gaussian 03 package, the Dipole moment, Molecular polarizability, Energy of the highest occupied molecular orbital(EHOMO), Energy of the lowest unoccupied molecular orbital(ELUMo) and Natural atomic charges of these compounds are tabulated. The data quantitative structure-activity relationship (QSAR) of these compounds are analyzed by the methods of multiple linear stepwise regressions study with software SPSS 16.0 for Windows. The QSAR study result shows that the main factors affecting the bioactivities of these thiourea compounds are Molecular polarizability and Energy of the highest occupied molecular orbital(EHOMO).