Title: Hypoxanthine
CAS Registry Number: 68-94-0
CAS Name: 1,7-Dihydro-6H-purin-6-one
Additional Names: purin-6(1H)-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; 1H-purin-6-ol; 3H-purin-6-ol; 9H-purin-6-ol; purin-6(3H)-one; 9H-purin-6(1H)-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
Hypusine IACFT Ibafloxacin Ibandronic Acid Iberiotoxin

CAS number 68-94-0 YesY
PubChem 790
ChemSpider 768 YesY
UNII 2TN51YD919 YesY
KEGG C00262 YesY
MeSH Hypoxanthine
ChEBI CHEBI:17368 YesY
Jmol-3D images Image 1
Molecular formula C5H4N4O
Molar mass 136.112
 YesY (verify) (what is: YesY/N?)
Except where noted otherwise, data are given for materials in their standard state (at 25 °C (77 °F), 100 kPa)
Infobox references

Hypoxanthine is a naturally occurring purine derivative. It is occasionally found as a constituent of nucleic acids, where it is present in the anticodon of tRNA in the form of its nucleoside inosine. It has a tautomer known as 6-hydroxypurine. Hypoxanthine is a necessary additive in certain cell, bacteria, and parasite cultures as a substrate and nitrogen source. For example,[1] it is commonly a required reagent in malaria parasite cultures, since Plasmodium falciparum requires a source of hypoxanthine for nucleic acid synthesis and energy metabolism.

In August 2011, a report, based on NASA studies with meteorites found on Earth, was published suggesting hypoxanthine and related organic molecules, including the DNA and RNA components adenine and guanine, may have been formed extraterrestrially in outer space.[2][3][4]