C ALLOXANTIN $ H 4 N 4 0 7.3H 2 0, a product obtained by the combination of alloxan and dialuric acid, probably possessing the constitution NH - CO CO - NH O - O - H NH - C CO - NH one of the three molecules of water being possibly constitutional.
Nencki has shown that alloxan combines with thiourea in alcoholic solution, in the presence of sulphur dioxide to form pseudothiouric acid, C 5 H 6 N 4 S0 3.