Is Tranexamic Acid natural?

Dominant commercial route hydrogenates petrochemical p-toluic acid to 4-methylcyclohexanecarboxylic acid, then installs the aminomethyl group by bromination and amination (Delepine-type chemistry) with trans-isomerization. No bio-based alternative route is used commercially.

The industrial synthesis of Tranexamic Acid (trans-4-(aminomethyl)cyclohexanecarboxylic acid) typically begins with the hydrogenation of terephthalic acid or its derivatives, followed by amination. A common route involves the catalytic hydrogenation of terephthalic acid to cyclohexane-1,4-dicarboxylic acid. This intermediate is then converted to the diamide, which is subsequently dehydrated to the dinitrile. The dinitrile undergoes further reduction and hydrolysis steps to yield the desired trans isomer of 4-aminomethylcyclohexanecarboxylic acid.

Alternatively, synthesis can proceed from p-toluic acid. This involves oxidation to terephthalic acid, followed by a series of reactions including esterification, reduction, and amination. Another significant pathway starts with the reduction of 4-cyanobenzoic acid to 4-(aminomethyl)benzoic acid, which is then hydrogenated to produce Tranexamic Acid. The hydrogenation steps often employ catalysts such as palladium on carbon (Pd/C) or rhodium-based catalysts under elevated hydrogen pressure and temperature.

Purification is a critical step to obtain cosmetic-grade Tranexamic Acid. This typically involves recrystallization from suitable solvents, such as water or aqueous alcohol mixtures, to remove impurities and ensure the desired stereochemistry (trans isomer). Ion-exchange chromatography may also be employed for further purification. The final product is usually obtained as a white crystalline powder.

Tranexamic Acid is a synthetic ingredient widely used in skincare for its remarkable ability to address hyperpigmentation and improve skin tone. It works by interfering with the pathway that leads to the overproduction of melanin, the pigment responsible for dark spots and uneven skin color. By inhibiting this process, it helps to visibly fade existing dark spots and prevent new ones from forming, leading to a brighter and more uniform complexion.

While it is a synthetic molecule, its structure is inspired by the amino acid lysine. It is produced through complex chemical processes that start with basic building blocks derived from petroleum. These processes involve multiple steps of chemical reactions, including hydrogenation and amination, to construct the precise molecular structure of Tranexamic Acid. Rigorous purification ensures its safety and efficacy for topical application.