Advances in structural modification of natural products with antimicrobial activity

Natural products, owing to their structural diversity and unique bioactivities, serve as valuable leads and promising candidates for tackling multidrug resistance (MDR) and developing novel antibiotics with enhanced antimicrobial potency. This review systematically evaluates the antibacterial potential of 90 representative compounds from 11 structural classes (including coumarins, lignans, quinones, flavonoids, chalcones, xanthones, terpenoids, alkaloids, marine-derived metabolites, essential oils, and others) reported between 2014 and 2025, with a focus on their mechanisms of action and structure-activity relationships. The findings aim to provide critical insights for combating MDR and facilitating the discovery of more effective natural antimicrobial agents.