title: Purine studies. 8. Formation of alkylthiopurines from 4,5-diaminopyrimidine- or purine-thiones by means of orthoester-anhydride mixtures.
mesh_terms: D000812:Anhydrides; D009682:Magnetic Resonance Spectroscopy; D011687:Purines / Q000138:chemical synthesis*; D011743:Pyrimidines; D013329:Structure-Activity Relationship; D013871:Thiones / Q000138:chemical synthesis
chemical_list: D000812:Anhydrides; D011687:Purines; D011743:Pyrimidines; D013871:Thiones