NMR Studies of a DNA Containing 8-Methoxydeoxyguanosine

Abstract

¹H NMR experiments have been undertaken to elucidate the structural effects of methoxy substitution at the C8 of a deoxyguanosine residue in a self-complementary dodecadeoxyribonucleotide, d(C-G-C-mo⁸G-A-A-T-T-C-G-C-G), duplex, which has an 8-methoxy-2′-deoxyguanosine (mo⁸dG) residue at the 4th position. NMR data indicate that the mo⁸dG residue takes an anti glycosidic conformation in a mo⁸dG(anti):dC(anti) base-pair structure in a B-form duplex. The thermal stability of the duplex is reduced, but the overall structure is much the same as that of the unmodified d(C-G-C-G-A-A-T-T-C-G-C-G) duplex.