2569. Creatinine

Nomenclature

CAS number: 60-27-5
2-Amino-1,5-dihydro-1-methyl-4H-imidazol-4-one; 2-amino-1-methyl-4-imidazolidinone; 1-methylhydantoin-2-imide; 1-methylglycocyamidine.
C4H7N3O; mol wt 113.12.
C 42.47%, H 6.24%, N 37.15%, O 14.14%.

Description and references

The end product of creatine catabolism. Normal constituent of urine; daily output about 25 mg/kg of body weight. Also found together with creatine in muscle tissues and blood. Occurs in all soils and in grain seeds and other vegetable matter. Has been found in certain fish and in crab meat extract. Isoln from urine: Maly, Ann. 159, 279 (1871); Folin, J. Biol. Chem. 17, 463 (1914); Benedict, ibid. 18, 183 (1914). The isoln from urine is tedious, and creatinine is usually prepd from commercial creatine by treatment with HCl: Edgar, Hinegardner, ibid. 56, 881 (1923); Org. Synth. 4, 15 (1925).

Chemical structure

Properties

Monoclinic plates. Leaflets from water. Dec about 300°. pKb (40°) 10.45. Sol in 12 parts water; slightly sol in alc. Practically insol in acetone, ether, chloroform.