Title: Xanthine
CAS Registry Number: 69-89-6
CAS Name: 3,7-Dihydro-1
H-purine-2,6-dione
Synonyms: 2,6(1
H,3
H)-purinedione; 2,6-dioxopurine
Molecular Formula: C5H4N4O2
Molecular Weight: 152.11
Percent Composition: C 39.48%, H 2.65%, N 36.83%, O 21.04%
Literature References: Occurs in animal organs, yeast, potatoes, coffee beans, tea. First isolated from urinary bladder stones:
Beilstein 26, 447 (1937). Prepd by treating a sulfuric acid soln of guanine with sodium nitrite: Fischer,
Ann. 215, 309 (1882). Several other syntheses,
cf. Levene, Bass,
Nucleic Acids (New York, 1931).
Properties: Scales, plates from water. Dec on heating without melting and with partial sublimation. Kb at 40° = 6.09′10-14; Ka at 40° = 1.19′10-10. Absorption spectrum: Kalckar,
J. Biol. Chem. 167, 429 (1947). One gram dissolves in 14.5 liters of water at 16°, in 1.4 liters boiling water; less sol in alcohol. Sol in mineral acids, freely sol in NH4OH and in NaOH solns.
Derivative Type: 1,3-Dimethylxanthine
see Theophylline
Derivative Type: 3,7-Dimethylxanthine
see Theobromine
Derivative Type: 1,3,7-Trimethylxanthine
see Caffeine