Title: Meconic Acid
CAS Registry Number: 497-59-6
CAS Name: 3-Hydroxy-4-oxo-4H-pyran-2,6-dicarboxylic acid
Additional Names: oxychelidonic acid
Molecular Formula: C7H4O7
Molecular Weight: 200.10
Percent Composition: C 42.02%, H 2.01%, O 55.97%
Literature References: From opium which contains 4 to 6%. Prepn: Thoms, Pietrulla, Ber. Pharm. Ges. 31, 4 (1921); Wibaut, Kleinpool, Rec. Trav. Chim. 66, 24 (1947).
Derivative Type: Monohydrate
Properties: Prisms from concd aq solns. One gram dissolves in 4 ml hot water, 50 ml methanol, 50 ml ethyl acetate, 100 ml acetone; freely sol in ethanol, benzene.
Derivative Type: Trihydrate
Properties: Orthorhombic pyramidal prisms from dil aq solns. Becomes anhydr when heated to 100-102° for 20 min. Dec with evolution of CO2 when heated to 120° or when boiled with water. The slight brown tint often characteristic of meconic acid prepns is due to traces of iron.