Pharmacy Freak Editorial Team

Introduction: 3D-QSAR approaches, especially CoMFA (Comparative Molecular Field Analysis), are powerful tools in rational drug design for B. Pharm students. CoMFA analyzes three-dimensional steric and electrostatic fields around aligned molecules to correlate molecular features with biological activity. Key concepts include molecular alignment, grid sampling, probe atom, partial charges, PLS (partial least squares) regression, contour maps, … Read more

Free-Wilson analysis is a practical QSAR method that decomposes biological activity into additive contributions of substituents on a common core. Ideal for B.Pharm students studying medicinal chemistry and drug design, the Free-Wilson method uses dummy (one-hot) variables and linear regression to estimate substituent effects, guiding lead optimization and SAR interpretation. Key concepts include the reference … Read more

Introduction: Hansch analysis is a cornerstone of QSAR (Quantitative Structure–Activity Relationship) studies used by B.Pharm students to relate chemical structure to biological activity. This method uses descriptors—hydrophobicity (π or LogP), electronic (Hammett σ), and steric (Taft Es)—within the Hansch equation to build multiple linear regression models that predict potency (e.g., pIC50). Key concepts include descriptor … Read more

Taft’s steric constant (Es) is a core concept in physical organic and pharmaceutical chemistry, quantifying steric hindrance of aliphatic substituents and helping predict how bulky groups affect reaction rates and mechanisms. This resource for B.Pharm students covers how Es is measured from ester hydrolysis kinetics, its use alongside the polar constant (σ*) in the Taft … Read more

Hammett’s substituent constant MCQs With Answer Hammett’s substituent constant (σ) is a cornerstone concept for B. Pharm students studying how aromatic substituents influence reactivity and drug properties. This introduction covers sigma values, sigma+, sigma–, resonance and inductive effects, the reaction constant (ρ), Hammett plots, linear free energy relationships (LFER), and applications in QSAR, SAR and … Read more