7959. Pyrazinoic Acid

Nomenclature

CAS number: 98-97-5
Pyrazinecarboxylic acid; pyrazinemonocarboxylic acid.
C5H4N2O2; mol wt 124.10.
C 48.39%, H 3.25%, N 22.57%, O 25.78%.

Description and references

Prepn by thermal decompn of 2,3-pyrazinedicarboxylic acid: Hall, Spoerri, J. Am. Chem. Soc. 62, 664 (1940); by oxidation of alkylpyrazines: Gainer, J. Org. Chem. 24, 691 (1959).

Chemical structure

Properties

Fine white needles from water, dec 225-229°. Sublimes. pK (25°) 2.92. Slightly sol in cold water, more sol in hot water. One gram dissolves in 120 g abs ethanol at 25°. Practically insol in ether, chloroform, benzene.

Derivative

Methyl ester.

Properties

Crystals from ether, mp 59°.

Derivative

Amide see Pyrazinamide.