Bioactive Coumarins: Bioorganic Strategies for Targeting Enzymes, Receptors, and DNA

Coumarins, a structurally diverse class of naturally occurring and synthetic compounds, have emerged as pivotal entities in modern bioorganic chemistry. Centered around the 2H-1-benzopyran-2-one scaffold, these molecules exhibit remarkable structural plasticity, enabling fine-tuned interactions with a broad spectrum of biological targets, including enzymes, nucleic acids, and cellular receptors. This review provides a detailed overview of bioactive coumarins and their growing importance as molecular modulators and scaffolds in drug discovery and design. Special emphasis is placed on their dual role as both therapeutic agents and diagnostic probes, capable of engaging in covalent and non-covalent interactions within biological systems. The discussion highlights how strategic structural modifications enhance coumarins’ specificity and potency toward key biological macromolecules. Mechanistic insights into coumarin-based enzyme inhibition are explored, particularly with respect to active and allosteric site binding, using representative examples involving dehydrogenases, DNA repair enzymes, and cytoskeletal proteins. Furthermore, the review delves into the interaction of coumarins with nuclear receptors, such as estrogen, glucocorticoid, and peroxisome proliferator-activated receptors, elucidating their roles in modulating neurological, cardiovascular, and immunological functions. Special attention is given to the nucleic acid-binding potential of coumarins, particularly their involvement in DNA intercalation and G-quadruplex stabilization, which are promising strategies in anticancer therapy. The review also examines recent advances in sustainable synthetic methodologies, including microwave-assisted and green chemistry approaches. Analytical tools like fluorescence spectroscopy and chromatographic techniques are emphasized for their critical role in evaluating structure–activity relationships and biological responses. Finally, the pharmacokinetic behavior, safety considerations, and emerging nanotechnology-enabled delivery systems are discussed. In vivo and clinical findings underscore the translational relevance of coumarins, particularly in oncology, infectious diseases, and neurodegenerative conditions. Looking ahead, coumarins stand out as versatile molecular platforms with immense potential to inspire innovative therapeutic strategies through interdisciplinary collaboration.