Exochelin siderophores: A review on synthetic pathways, iron scavenging, and therapeutic strategies in antimycobacterial applications.

Exochelin siderophores are an important class of iron-chelating molecules with significant potential in combating mycobacterial infections. They are a structurally distinctive class of peptidic siderophores produced predominantly by saprophytic mycobacteria that play a critical role in extracellular ferric ion acquisition. This review examines the chemical synthesis of exochelin siderophores, their ferric(III) chelation thermodynamics and coordination chemistry, and the emerging translational potential of siderophore-based antimycobacterial strategies. We critically assess the current state of synthetic methodologies, highlight structure-activity relationships governing metal selectivity, and evaluate the "Trojan horse" drug delivery paradigm and iron-deprivation approaches against Mycobacterium tuberculosis. Key gaps in scalable total synthesis, in vivo chelation validation, and clinical translation are identified, with a view toward guiding future organic chemistry-driven innovations in this field.