Title: Hypoxanthine
CAS Registry Number: 68-94-0
CAS Name: 1,7-Dihydro-6
H-purin-6-one
Synonyms: purin-6(1
H)-one; sarcine; sarkin
Molecular Formula: C5H4N4O
Molecular Weight: 136.11
Percent Composition: C 44.12%, H 2.96%, N 41.16%, O 11.75%
Literature References: Desmotropic forms: purin-6-ol; 1
H-purin-6-ol; 3
H-purin-6-ol; 9
H-purin-6-ol; purin-6(3
H)-one; 9
H-purin-6(1
H)-one. Formed in the animal body during the breakdown of nucleic acids; formation from adenosine continues after death. Also widely distributed in the vegetable kingdom. Numerous syntheses,
e.g., from 2,6,8-trichloropurine: Fischer,
Ber. 30, 2226 (1897); by oxidation of adenine: Krüger,
Z. Physiol. Chem. 18, 445 (1894). By reduction of uric acid: Sundwik,
ibid. 76, 486 (1912); by condensing ethyl cyanoacetate and thiourea in the presence of Na-ethoxide: Traube,
Ann. 331, 64 (1904); from mercapto-4-hydroxy-6-aminopyrimidine: Taylor, Cheng.
J. Org. Chem. 25, 148 (1960).
Reviews: Levene, Bass,
ACS Monograph Series no. 56, entitled "Nucleic Acids" (New York, 1931); Chargaff, Davidson,
Nucleic Acids vols. I & II (Academic Press, New York, 1955).
Properties: Small octahedra, needles from water, dec 150° without melting. Sol in 1400 parts water, 70 parts boiling water; sol in dil acids, alkalies. Combines with one equivalent of acid or with two equivalents of base. pKb (25°): 8.7. Absorption spectrum: Dhere,
Compt. Rend. 141, 720.
pKa: pKb (25°): 8.7