A one-step synthesis of regioisomeric N- and O-benzylated 8-bromoguanines 4
, 5, 9, 10 via N-2-acetyl-8-bromoguanine (2) is described. The possibility
to prepare 8-oxo- and 8-chloroguanine derivatives 3, 11, 12 from the same c
ompound 2 is demonstrated. H-1 and C-13 NMR spectra are used to locate the
sites of aralkylation.