Methylation of adenosine and related nucleosides with trimethylselenonium hydroxide, and regiospecific effects of copper(II) ions

Abstract

Methylation of adenosine, deoxyadenosine, 6-N-methyladenosine and 2′(3′)-O-methyladenosines with trimethylselenonium hydroxide was studied in the presence and absence of copper(II) acetylacetonate [Cu(AA)₂]. It was found that copper(II) ions promoted methylation of the 2′(3′)-OH groups of the ribonucleosides but suppressed methylation at the N-1 position of the adenine rings. The metal-ion effects are discussed in conjunction with a catalytic role for Cu(AA)₂ in the reactions.