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Second generation silver(I)-mediated imidazole base pairs.

ABSTRACT: The imidazole-Ag(I)-imidazole base pair is one of the best-investigated artificial metal-mediated base pairs. We show here that its stability can be further improved by formally replacing the imidazole moiety by a 2-methylimidazole or 4-methylimidazole moiety. A comparison of the thermal stability of several double helices shows that the addition of one equivalent of Ag(I) leads to a 50% larger increase in the melting temperature when a DNA duplex with methylated imidazole nucleosides is applied. This significant effect can likely be attributed to a better steric shielding of the metal ion within the metal-mediated base pair.

SUBMITTER: Hensel S

PROVIDER: S-EPMC4168905 | biostudies-literature | 2014

REPOSITORIES: biostudies-literature

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Second generation silver(I)-mediated imidazole base pairs.

Hensel Susanne S Megger Nicole N Schweizer Kristina K Müller Jens J

Beilstein journal of organic chemistry 20140909

The imidazole-Ag(I)-imidazole base pair is one of the best-investigated artificial metal-mediated base pairs. We show here that its stability can be further improved by formally replacing the imidazole moiety by a 2-methylimidazole or 4-methylimidazole moiety. A comparison of the thermal stability of several double helices shows that the addition of one equivalent of Ag(I) leads to a 50% larger increase in the melting temperature when a DNA duplex with methylated imidazole nucleosides is applied ...[more]

PMID: 25246972

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