Nomenclature
CAS number: 497-59-6
3-Hydroxy-4-oxo-4
H-pyran-2,6-dicarboxylic acid; oxychelidonic acid.
C
7H
4O
7; mol wt 200.10.
C 42.02%, H 2.01%, O 55.97%.
Description and 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
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
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.