QSAR presentation

introduction of QSAR

1. QSAR

2. SAR SAR is relationship between the chemical structure of a molecule and its biological activity refined to build mathematical relationship between chemical structure and the biological activity .

3. QSAR A quantitative structure activity relationship (QSAR) is a mathematical relationship which corelates measurable or calculable molecular properties to some specific biological activity in terms of an equation. It is computerized statistical method of drug designing.

4. QSAR Physiochemical parameters: Solubility Partition coefficient Protein binding Log P (biological activity) QSAR also applies mathematically derived formulas. Numerical parameters

5. O bjectives of QSAR P rediction of biological activity with their parameters or their nature or position of substitution. QSAR gives positive influence on compound to be guessed. Understanding the mechanism of action of drug. Lead compound search by CADD. Economise the new drug development. Reduction of usage of animals Minimize random synthesis .

6. Partition coefficient It is ratio of concentrations of the unionized drug or compound between two liquid phase. The log of ratio of concentration of the unionized solute in the solvent is called log P. One of the solvent is water and other one is non polar solvent. Log p value is also known as a measure of lipophilicity.

7. Taft steric parameter T he interaction of drug with its receptor is influenced by steric factor of drug. The bulk nature of drug size and shape influence its binding capacity with enzyme or receptor. Steric parameter uses a computer programme to calculate the steric substituent values like vanderwaals radius, bond length, bond angles etc. This effect is reflected for duration of action.

8. Data analysis T he data of biological activity and the values of parameters generated by software should be analysed to get a meaningful QSAR model (lead model) QSAR model is considered as a LEAD model to enter into preclinical and clinical trials. It helps to know the better pharmacological activity.