Synthesis of new amide derivatives of phenolic acids with antioxidant properties for use in cosmetics

Hydroxycinnamic acids, belonging to the group of phenolic acids, are natural plant compounds widely found in fruits, vegetables, grains, seeds, nuts, and medicinal plants. They are produced in plants as a result of metabolic transformations of the shikimic acid pathway and serve as a protective agent against environmental factors such as UV radiation, oxidative stress, and microorganisms. 

Phenolic acids exhibit strong antioxidant properties thanks to their ability to neutralize free radicals and inhibit lipid peroxidation. They also have anti-inflammatory, antimicrobial, anticancer, and anti-aging properties, which is why they are widely used in cosmetology and pharmacy. Caffeic acid protects cells from oxidative stress and stimulates collagen synthesis, supporting skin regeneration and delaying the aging process. Ferulic acid exhibits photoprotective properties, absorbs UV radiation, and stabilizes other antioxidants, such as vitamins C and E, increasing their effectiveness. p-coumaric acid, in turn, supports cell protection against oxidative damage and has antibacterial and anti-inflammatory properties.

In recent years, there has been growing interest in the chemical modification of phenolic acids, particularly through the preparation of their amide derivatives with biogenic amines and amino acids. These derivatives often exhibit greater chemical stability, better solubility, and higher biological activity than the parent compounds, increasing their potential for use in cosmetic formulations.

The aim of this study was to synthesize caffeic, ferulic, and p-coumaric acid derivatives and evaluate their antioxidant properties using spectrophotometric methods for use in cosmetics. The possibility of using boronic acid-catalyzed reactions with microwave-assisted synthesis was investigated.