title: Carbon-13 magnetic resonance. XXII. The N-methylpurines.
mesh_terms: D002247:Carbon Isotopes; D007093:Imidazoles; D009682:Magnetic Resonance Spectroscopy; D008745:Methylation; D011522:Protons; D011687:Purines
chemical_list: D002247:Carbon Isotopes; D007093:Imidazoles; D011522:Protons; D011687:Purines