Details on Ozonolyses of Substituted Cyclopentenes

Die Bildung und Stabilität monomerer Ozonide von Cyclopentenen werden in Abhängigkeit von der Substitution studiert. Bisherige Annahmen müssen revidiert werden, eine mechanistische Alternative über oxygenierende Ringerweiterung (Monosauerstoff-Transfer) und anschließende peroxidische Verbrückung (Disauerstoff-Transfer) wird diskutiert.Formation and stability of monomeric ozonides of cyclopentenes are studied depending upon substitution. Assumptions hitherto made must be revised. A mechanistic alternative including a sequence of oxygenative ring-enlargement (Transfer of one oxygen) and final formation of a peroxide bridge (Transfer of two oxygens) is discussed

Details on Ozonolyses of Substituted Cyclopentenes

Die Bildung und Stabilität monomerer Ozonide von Cyclopentenen werden in Abhängigkeit von der Substitution studiert. Bisherige Annahmen müssen revidiert werden, eine mechanistische Alternative über oxygenierende Ringerweiterung (Monosauerstoff-Transfer) und anschließende peroxidische Verbrückung (Disauerstoff-Transfer) wird diskutiert.Formation and stability of monomeric ozonides of cyclopentenes are studied depending upon substitution. Assumptions hitherto made must be revised. A mechanistic alternative including a sequence of oxygenative ring-enlargement (Transfer of one oxygen) and final formation of a peroxide bridge (Transfer of two oxygens) is discussed

Theoretical and Experimental Study of Charge Transfer through DNA: Impact of Mercury Mediated T‑Hg‑T Base Pair

DNA-Hg complexes may play an important role in sensing DNA defects or in detecting the presence of Hg in the environment. A fundamental way of characterizing DNA-Hg complexes is to study the way the electric charge is transferred through the molecular chain. The main goal of this contribution was to investigate the impact of a mercury metal cation that links two thymine bases in a DNA T-T mismatched base pair (T-Hg-T) on charge transfer through the DNA molecule. We compared the charge transfer efficiencies in standard DNA, DNA with mismatched T-T base pairs, and DNA with a T-Hg­(II)-T base pair. For this purpose, we measured the temperature dependence of steady-state fluorescence and UV–vis of the DNA molecules. The experimental results were confronted with the results obtained employing theoretical DFT methods. Generally, the efficiency of charge transfer was driven by mercury changing the spatial overlap of bases