Butyrolactone, also known as gamma-Butyrolactone, is tetrahydrofuran with an oxo group substituted at position two. Its role is that of a neurotoxin and metabolite. The compound comes in the form of a clear, colorless liquid with an oily feel and a mild odor. It can be found in the makeup of paint removers, drilling oils, and textile aids. The molecular weight of butyrolactone is 86.09 g/mol. It has a hydrogen bond donor count of zero, a hydrogen bond acceptor count of two, and a rotatable bond count of zero. It has an exact and monoisotopic mass of 86.04 g/mol. The heavy atom count of butylamine is six. It also has a complexity of 67.9 and is a canonicalized compound. Butyrolactone has a boiling point of 399 °F (204°C) and a melting point of -49 °F (-43 °C). It also has a flashpoint of 209 °F (98 °C) and is soluble in water at 100 mg/mL at 55°F.