title: The x-ray structures of 7-aminofurazano (3,4-d)pyrimidine and 7-amino-1,2,5-thiadiazolo(3,4-d)pyrimidine.
mesh_terms: D003461:Crystallography; D005663:Furans; D011743:Pyrimidines
chemical_list: D005663:Furans; D011743:Pyrimidines