Abstract
Natural products are investigated for their remunerative effects on health.
Quercetin, a flavonoid, is commonly distributed in vegetables and fruits. Quercetin is
used as a supplement in food and as a phytochemical remedy against several diseases,
including circulatory dysfunction, neurodegeneration, diabetes, cancer, and
inflammation. The most prominent property of quercetin is its antioxidant activity,
enabling it to douse free radicals. Derivatives of quercetin are essential metabolites,
and even various conjugates are being advocated by the Food and Drug Administration
(FDA) for use in humans. So, the biosynthesis of quercetin derivatives is a predominant
field of research. Methylation and glycosylation are two essential strategies used to
synthesize various metabolites of quercetin that do not exist in nature. This review summmarizes quercetin chemistry, structural modifications, Structure-Activity
Relationship (SAR) studies, and therapeutic applications of quercetin.