Natural Hydroxybenzoic and Hydroxycinnamic Acids Derivatives: Mechanisms of Action and Therapeutic Applications López-Herrador, Sergio Corral-Sarasa, Julia González-García, Pilar Morillas-Morota, Yaco Olivieri, Enrica Jiménez-Sánchez, Laura Díaz-Casado, María Elena Hydroxybenzoic acid Hydroxycinnamic acids Therapeutic applications Hydroxybenzoic and hydroxycinnamic acid derivatives are a class of organic compounds derived from benzoic and cinnamic acid, respectively, two types of acids in which one of the hydrogen atoms on the benzene ring is replaced by a hydroxyl (-OH) or alkoxyl group (-O-R). These compounds are found in a wide range of natural sources, particularly in plants, as well as in some fungi. Their biological properties are distinctive, as they combine antioxidant, anti-inflammatory, and metabolic functions, which can be utilized for therapeutic purposes in humans. In this review, we identify the most relevant hydroxybenzoic and hydroxycinnamic acid derivatives for human applications, explain their common and specific mechanisms of action, and highlight their applications in significant preclinical and clinical studies. 2025-07-04T11:50:05Z 2025-07-04T11:50:05Z 2025-06-11 journal article López-Herrador, S.; Corral-Sarasa, J.; González-García, P.; Morillas-Morota, Y.; Olivieri, E.; Jiménez-Sánchez, L.; Díaz-Casado, M.E. Natural Hydroxybenzoic and Hydroxycinnamic Acids Derivatives: Mechanisms of Action and Therapeutic Applications. Antioxidants 2025, 14, 711. [DOI: 10.3390/antiox14060711] https://hdl.handle.net/10481/105083 10.3390/antiox14060711 eng http://creativecommons.org/licenses/by/4.0/ open access Atribución 4.0 Internacional MDPI