Psoralen: A Biologically Important Coumarin with Emerging Applications

Coumarin belongs to a class of lactones that are fundamentally comprised of a benzene ring fused to an α-pyrone ring; these lactones are known as benzopyrones. Similarly, coumarin has a conjugated electron-rich framework and good charge-transport properties. Plants produce coumarin as a chemical response to protect themselves from predation. Coumarins are used in different products, such as cosmetics, additives, perfumes, aroma enhancers in various tobaccos and some alcoholic drinks, and they play a relevant role in natural products and in organic and medicinal chemistry. In addition, as candidate drugs, many coumarin compounds have strong pharmacological activity, low toxicity, high bioavailability and better curative effects and have been used to treat various types of diseases. Various endeavors were made to create coumarin-based anticoagulant, antimicrobial, antioxidant, anticancer, antidiabetic, antineurodegenerative, analgesic and anti-inflammatory agents. A class of chemical compounds called furocoumarins has phototoxic properties and is naturally synthesized via the fusion of coumarin to a furan ring in different plant species. Psoralens belong to the furocoumarin class and occur naturally in various plants, e.g., lemons, limes, and parsnips. Angelicin is an isomer of psoralens, and most furocoumarins, e.g., xanthotoxin, bergapten, and nodekenetin, are derivatives of psoralens or angelicin. The present work demonstrated that psoralen molecules exhibit anti-tumoral activity against breast cancer and influence different intracellular signals to maintain the high survival of breast cancer cells. Psoralens perform different functions, e.g., antagonize metabolic pathways, protease enzymes, and cell cycle progression and even interfere in the crosslinking between receptors and growth factor mitogenic signaling.