Pharmaceutical drug discovery is an expensiveand timeconsuming process.Thedevelopmentofadrugfromaninitialideatoitsentryintothemarketisaverycomplex processwhichcantakearound5-10yrs.andcostisvery highuptobillion.Itisan developmentprocessinvolvesuseof variety of computationaltechniques,such as structureactivity relationship,quantitativestructureactivity relationship,molecular mechanics,quantam mechanics,moleculardynamicsand drug protein docking. The ideaforanewdevelopmentcancomefromavarietyofsourceswhichincludethe currentnecessitiesofthemarket,newemergingdiseases,academicandclinical research,commercialsector.Thepharmaceuticalindustryisunderpressurein developingcosteffectivenessdrugmoleculefromthepreviousknowledgeand establishedQuantitativeStructureActivityRelationships.Thestructurebaseddesignis oneof reliableandpromisingtechniquesusedindrugdesigning.Indrugdesign,the mainaimisto?ndoutthethreedimensionalstructureof pharmacologically signi?cant receptorligandcomplexes.Theaimofthisreviewistogiveanoverviewontherational drugdesign approacheswith a casestudy on drugdiscovery forin?uenza Avirus,HER2Receptor,targetingdopamineD3receptor,purpose,andapplicationsofQSAR. Thisarticlehighlightthebene?tsandpromisesofdevelopingtoolsfordrugdiscovery.
Introduction
Overview of Drug Design
Drug design is an integrated scientific process aimed at creating "tailored drugs" that interact specifically with biological targets. It heavily uses computational methods such as:
Drug behavior in the body (biosynthesis region) influences its action—positive (therapeutic) or negative (toxic). Drug design is often done through Computer-Aided Drug Design (CADD), which includes structure-based and ligand-based methods.
Lipinski's Rule of Five (Drug-likeness Criteria)
A drug is likely to be orally active if it has:
≤ 5 hydrogen bond donors
≤ 10 hydrogen bond acceptors
Molecular mass < 500 Daltons
logP (partition coefficient) ≤ 5
Docking
Docking simulates the binding of a small molecule (ligand) to a target protein: