Galactosamine

Galactosamine is a hexosamine derived from galactose with the molecular formula C6H13NO5. This amino sugar is a constituent of some glycoprotein hormones such as follicle-stimulating hormone (FSH) and luteinizing hormone (LH). Other sugar constituents of FSH and LH include glucosamine, galactose and glucose.
Galactosamine is a hepatotoxic, or liver-damaging, agent that is sometimes used in animal models of liver failure.