Mechanistic aspects of the oxidation of 1,3-disubstituted 6-amino-5-nitrosouracils with lead tetraacetate: the formation of pyrimido[5,4-g]pteridinetetrone 10-oxides
                                
                                    
                                        作者:Magoichi Sako、Seiji Ohara、Kosaku Hirota、Keuji Kano、Yoshifumi Maki、Edward C. Taylor                                    
                                    
                                        DOI:10.1021/jo00022a017
                                    
                                    
                                        日期:1991.10
                                    
                                    Lead tetraacetate oxidation of 1,3-disubstituted 6-amino-5-nitrosouracils 1 in glacial acetic acid results in the formation of 1,3,6,8-tetrasubstituted pyrimido[5,4-g]pteridine-2,4,5,7(1H,3H,6H,8H)-tetrone 10-oxides 2.  ESR studies and a number of chemical observations suggest a novel reaction sequence involving oxidative dimerization of 1 followed by intramolecular cyclization, oxidation, and homolytic elimination of nitrous oxide.