Quinic acid is a cyclitol, a cyclic polyol, and a cyclohexanecarboxylic acid. It is a crystalline acid obtained from cinchona bark, coffee beans, and other plant products and made synthetically by hydrolysis of chlorogenic acid. Quinic acid is also implicated in the perceived acidity of coffee. It is a constituent of the tara tannins. Quinic acid is used as an astringent. By its presence, it serves to distinguish genuine barks. It can be found in the bark of Eucalyptus globulus. This acid is a versatile chiral starting material for the synthesis of new pharmaceuticals. A medication for the treatment of influenza A and B strains called Tamiflu has been successfully developed and launched into the market. Quinic acid is also thought to displace binding of the mu opioid receptor antagonist; however, this acid was originally thought to be pharmacologically inactive.