C8H13N5O5, triclinic, P (1) over bar (no. 2), a = 9.1462(4) angstrom, b = 9.9732(5) angstrom, c = 13.5252(6) angstrom, alpha = 90.098(2)degrees, beta = 91.031(2)degrees, gamma = 109.874(2)degrees, V = 1160.02(9) angstrom(3), Z = 4, R-gt(F)= 0.0392, wR(ref)(F-2) = 0.1015, T = 150(2) K.