Effect of ionic state of 2'-deoxyguanosine and solvent on its aralkylation by benzyl bromide.
To extend studies of the aralkylation of nucleic acid components under a variety of solvent conditions, we determined product distributions from the reactions of benzyl bromide with 2'-deoxyguanosine and the anion of 2'-deoxyguanosine in 2,2, 2-trifluoroethanol (TFE) and compared these distributions with those from the reaction of the anion with benzyl bromide in N, N-dimethylacetamide (DMA). 7-Benzylguanine was the only benzylated product detected in the reaction with the neutral nucleoside in TFE. In striking contrast, the reaction of the anion of 2'-deoxyguanosine with benzyl bromide in TFE produced N2-benzyl-2'-deoxyguanosine in significant yield and with high selectivity. The reaction of the anion of 2'-deoxyguanosine with benzyl bromide in DMA produced products derived only from reaction at the 1- and/or 7-position of the nucleoside. The weakly nucleophilic but protic polar solvent TFE and the iminolate tautomeric form of the 2'-deoxyguanosine anion appear to be essential for benzylation at the exocyclic N2-position.
Moon
K Y
KY
Chemistry of Carcinogenesis Laboratory, ABL-Basic Research Program, NCI-Frederick Cancer Research and Development Center, P.O. Box B, Frederick, Maryland 21702, USA.
Moschel
R C
RC
D001593:Benzyl Compounds / Q000378:metabolism*; D003849:Deoxyguanosine / Q000378:metabolism*; D012997:Solvents
D001593:Benzyl Compounds; D012997:Solvents; D003849:Deoxyguanosine; C038682:benzyl bromide