title: Purine N-oxides. LVII. 9-Hydroxyhypoxanthine, xanthine, and guanine.
mesh_terms: D002849:Chromatography, Gas; D003500:Cyclization; D006147:Guanine / Q000138:chemical synthesis; D007042:Hypoxanthines / Q000138:chemical synthesis; D007093:Imidazoles / Q000138:chemical synthesis; D008722:Methods; D011688:Purinones / Q000138:chemical synthesis*; D013057:Spectrum Analysis; D014970:Xanthines / Q000138:chemical synthesis
chemical_list: D007042:Hypoxanthines; D007093:Imidazoles; D011688:Purinones; D014970:Xanthines; D006147:Guanine