An acetal has two ether functions at a single carbon atom. The ACID saponins possess triterpenoid structures. However, a branch occurs, after the formation of the triterpenoid hydrocarbon, squalene , that leads to steroids in one direction and to cyclic triterpenoids in the other. Glycyrrhiza is the dried rhizome and roots of Glycyrrhiza glabra. Upon hydrolysis, the glycoside loses its sweet taste and is converted to the aglycone glycyrrhetinic acid plus two molecules of glucuronic acid.
Glycyrrhetinic acid is a pentacyclic triterpenoid derivative of the beta-amyrin type.
Expectorants are used to decrease the viscosity of tenacious mucus, or to increase the secretion of mucus in dry irritant unproductive cough, thereby, lubricating the air passages and making coughing more productive. It is used considerably as a flavoring agent and is frequently employed to mask the taste of bitter drugs such as aloe, quinine etc. This causes an increased level of prostaglandins in the digestive system. Prostaglandins inhibit gastric secretion but stimulate pancreatic secretion and mucous secretion in the intestines and markedly increase intestinal motility. They also cause cell proliferation in the stomach.