The pH-Dependence of the Hydration of 5-Formylcytosine: an Experimental and Theoretical Study

5-Formylcytosine is an important nucleobase in epigenetic regulation, whose hydrate form has been implicated in the formation of 5-carboxycytosine as well as oligonucleotide binding events. The hydrate content of 5-formylcytosine and its uracil derivative has now been quantified using a combination of NMR and mass spectroscopic measurements as well as theoretical studies. Small amounts of hydrate can be identified for the protonated form of 5-formylcytosine and for neutral 5-formyluracil. For neutral 5-formylcytosine, however, direct detection of the hydrate was not possible due to its very low abundance. This is in full agreement with theoretical estimates

Tricyanated Ferrocenes;Isolation, structure, electrochemistry and DFT calculations

1,2,3- Tricyanoferrocene and 1,3-dibromo-2,4,5-tricyanoferrocene have been synthesized via metallation and usage of dimethylmalononitrile (DMMN) as cyanating agent. They are the first compounds where three nitrile functions could be introduced into the ferrocene sceleton. Further studies on the electrophilic cyanation of lithiated haloferrocenes [Fe(C5HmX4-mLi)(C5H5)] (X=Cl, Br;m=0-3) show the formation of complex mixtures of cyano-halo-ferrocenes [Fe{C5HmX5-m-n(CN)(n)}(C5H5)] (m=0-3, n=0-3) most likely induced by halogen-dance reactions. The molecular and crystal structures of [Fe{C5H2(CN)(3)}(C5H5)] and [Fe(C5Cl4CN)(C5H5)] are discussed. Cyclic voltametric studies of both tricyanoferrocenes show irreversible oxidations at very high potentials (E-onset approximate to 845 mV and 945 mV, respectively, vs FcH/FcH(+))

Ferrocenes with a Persulfurated Cyclopentadienyl Ring: Synthesis, Structural Studies, and Optoelectronic Properties

Persulfurated arenes are a fascinating class of functional molecules with a wide range of potential applications. Ferrocenes are also a multifaceted class of aromatic compounds that can easily be finetuned for an enormous variety of desired properties. A combination of both substance classes might yield an even wider field of applications. Herein, we describe the synthesis of two ferrocenes with one persulfurated cyclopentadienyl ring [C5(SR)5], with R=Me or Ph, together with their crystal structures, optical, and electrochemical properties. Both crystal structures show significant intramolecular sulfur‐iron interactions as well as weak intermolecular sulfur– contacts. Cyclovoltammetry of the [C5(SPh)5] compound shows a high oxidation potential of 651 mV vs. FcH/FcH+