NMR and X‐ray structural studies on 3‐benzyl‐8‐bromoadenine

Abstract

Abstract8‐Bromoadenine was benzylated in the presence of base to give a mixture of two regioisomers. One was easily recognized as 9‐benzyl‐8‐bromoadenine, but the other structure could not be determined with absolute certainty by NMR. Therefore, X‐ray crystallography was used to prove that the benzyl group was attached to N‐3. Furthermore, it is shown that the 3‐benzyl adenine derivative exists as the amine tautomer both in the crystalline state as well as in solution (DMSO‐d6), with restricted rotation around the N6C6 bond. J. Heterocyclic Chem., (2011).

Solvent‐directed Regioselective Benzylation of Adenine: Characterization of N9‐benzyladenine and N3‐benzyladenine

“…This research was conducted to add to the growing data showing that adenine reacts at the N9 and N3 positions . NMR data have routinely been misinterpreted, but a thorough analysis in three solvents leads to unambiguous interpretation and is well supported by computational predictions using Amsterdam Density Functional (ADF) RB3LYP/ATZP/COSMO.…”

Synthetic Routes to N-9 Alkylated 8-Oxoguanines; Weak Inhibitors of the Human DNA Glycosylase OGG1

“…The 8-oxo derivatives of guanosine or deoxyguanosine are probably not inhibitors of the glycosylases since they themselves may be substrates for the enzymes that cleave N , O -acetals in nucleic acids. As a continuance of our synthetic studies directed towards 9-substituted 8-oxoadenines [8,9], we herein present strategies for the synthesis of N -9 substituted 8-oxoguanines. Previous routes include rather tedious constructions of the guanine ring system [10,11,12], and hydrolysis of purine precursors; hydrolysis of 8-halopurines [13,14,15,16], or less conveniently hydrolysis of N -7 functionalizedpurines [11,17,18,19].…”