STRUCTURE–ACTIVITY RELATIONSHIP AND GREEN CHEMISTRY ASSESSMENT OF BIOACTIVE HETEROCYCLIC COMPOUNDS: AN INTEGRATED EXPERIMENTAL AND COMPUTATIONAL APPROACH

Abstract

Bioactive heterocyclic compounds provide adaptable molecular frameworks for exploring antioxidant and antimicrobial properties, yet the prioritization of promising analogues requires more than ranking biological response alone. This article presents an integrated workflow that links molecular modification, experimental activity profiling, computational interpretation, and green chemistry assessment. Structure–activity relationship (SAR) analysis is framed around changes in electronic character, steric demand, hydrogen-bonding capacity, lipophilicity, polarity, and scaffold geometry. Computational tools—including molecular descriptor calculation, density functional theory (DFT), and molecular docking where a justified biological target is available—are positioned as complementary methods for interpreting experimental trends rather than substitutes for biological validation. Sustainability is evaluated using isolated yield, process mass intensity (PMI), E-factor, solvent burden, catalyst recovery, reaction time, and energy use under explicitly defined process boundaries. Worked-example tables illustrate how compounds can be compared through a multi-parameter decision framework without implying that the example values are empirical. The proposed approach supports transparent selection of candidates that balance activity, physicochemical suitability, synthetic practicality, and environmental performance. Its principal recommendation is to use experimental evidence, computational hypotheses, and sustainability metrics together, while retaining clear distinctions between measured data, predicted properties, and illustrative scenarios.