Interaction of beryllium derivatives with N-methylated DNA bases: 9-methylguanine and 1-methylcytosine
The effect of beryllium bonds (BeB) on the tautomerism of 9-methyl-guanine and 1-methylcytosine has been theoretically studied at MP2/aug-cc-pVDZ computational level. It is predicted that BeB will be able to strongly modify the tautomeric behaviour of these nucleobases and, by extension, of DNA and RNA bases. Thus, while the oxo-amino is the most stable tautomer for 9-methyl-guanine and 1-methylcytosine when isolated, they present a relative energy above 33 and 17 kJ mol−1, respectively, with respect to the most stable tautomer when they form complexes with BeR2 systems (amino-hydroxy and imino-oxo, respectively). In both cases, the most stable complexes are associated to N⋯Be interactions with binding energies up to 180 kJ mol−1.