Copper(ii)-mediated base pairing involving the artificial nucleobase 3H-imidazo[4,5-f]quinolin-5-ol.

Different N3-substituted derivatives of the new ligand 3H-imidazo[4,5-f]quinolin-5-ol were synthesized. The three pKa values of its nucleoside derivative 1 were determined as 2.72 ± 0.

Metal-mediated base pairing in DNA involving the artificial nucleobase imidazole-4-carboxylate.

The use of imidazole-4-carboxylate (X) as an artificial nucleobase in metal-mediated base pairing is reported. Towards this end, the corresponding deoxyribonucleoside was synthesized and structurally characterized as its sodium salt (sodium 1,2-dideoxy-1-(4-carboxyimidazol-1-yl)-d-ribofuranose). The deoxyribonucleoside was incorporated into different DNA duplexes (parallel-stranded and antiparallel-stranded), and their Cu(II)- and Ag(I)-binding behavior was investigated.

A metal-mediated base pair that discriminates between the canonical pyrimidine nucleobases.

A nucleoside analogue comprising the ligand 1-imidazo[4,5-][1,10]phenanthroline () was applied to develop a molecular beacon capable of discriminating the canonical nucleobases cytosine and thymine. The beacon is based on the formation of a stable Ag-mediated base pair between and cytosine, whereas the presence of Ag strongly destabilizes nucleic acids comprising an artificial base pair between and thymine. Metal-mediated base pair formation was investigated by temperature-dependent UV spectroscopy and CD spectroscopy and complemented by extensive DFT calculations.