Nitrosative adenine deamination: facile pyrimidine ring-opening in the dediazoniation of adeninediazonium ion.
[reaction: see text]. Dediazoniation of adeninediazonium ion, 1, forms the heteroaromatic cation, 2. Ab initio studies at the CCSD(fc)/6-31G**//MP2(full)/6-31G** level now reveal that the cyclic cation 2 is kinetically and thermodynamically unstable with respect to the pyrimidine ring-opened cation, 3. The results suggest that 4-cyano-5-isocyano-imidazole, 4, and 4,5-dicyanoimidazole, 5, might be formed to some extent in nitrosative deaminations of adenine.
Department of Chemistry, University of Missouri-Columbia, Columbia, Missouri 65211, USA.
Brian
B
Hodgen
Sundeep
S
Rayat
Rainer
R
Glaser
D000225:Adenine / Q000031:analogs & derivatives / Q000737:chemistry*; D003641:Deamination; D003979:Diazonium Compounds / Q000737:chemistry*; D007093:Imidazoles / Q000737:chemistry; D008956:Models, Chemical; D008958:Models, Molecular; D015394:Molecular Structure; D013816:Thermodynamics
C110830:4,5-dicyanoimidazole; D003979:Diazonium Compounds; D007093:Imidazoles; D000225:Adenine