The present invention broadly relates to racemic or optically active 5-substituted 3,4-dihydroxy-2(5H)-furanone compounds and their pharmaceutically acceptable salts, useful for treating a pathology in which reactive oxygen species and inflammatory mediators are contributing deleterious factors, such as acute or chronic inflammatory disorders, for example, asthma, rheumatoid arthritis, inflammatory bowel disease, and acute respiratory distress syndrome; neurodegenerative disorders, such as Alzheimer disease, Parkinson disease, amyotrophic lateral sclerosis, traumatic brain injury and multiple sclerosis; cardiovascular diseases, such as atherosclerosis; viral diseases, such as AIDS; skin diseases, such as psoriasis, sunburn and premature aging; and eye diseases, such as glaucoma, cataract, senile macular degeneration, inflammatory eye conditions, trauma, post-traumatic eye disorders, diabetic retinopathy, and eye infections.