1H-purine-2,6,8(3H,7H,9H)-trione-13C 15N2;7,9-Dihydro-1H-Purine-2,6,8(3H)-trione-13C 15N2; 1H-Purine-2,6,8-triol-13C 15N2; 2,6,8-Trihydroxypurine-13C 15N2; 2,6,8-Trioxopurine-13C 15N2; 2,6,8-Trioxypurine-13C 15N2; Lithic Acid-13C 15N2; Purine-2,6,8(1H,3H,9H)-trione-13C 15N2;