title: [Studies on the synthesis of sulfur containing pyrimido [5,4-d]pyrimidine derivatives. II. Syntheses and rearrangement of 2-methylsulfonyl pyrimido[5,4-d]pyrimidine-6-sulfonamide derivatives].
mesh_terms: D055598:Chemical Phenomena; D002621:Chemistry; D011743:Pyrimidines / Q000138:chemical synthesis*; D013449:Sulfonamides / Q000138:chemical synthesis*
chemical_list: D011743:Pyrimidines; D013449:Sulfonamides