We report the discovery of a new bioorthogonal click-and-release reaction involving iminosydnones and strained alkynes. This transformation leads to two products resulting from the ligation and fragmentation of iminosydnones under physiological conditions. Optimized iminosydnones were successfully used to design innovative cleavable linkers for protein modification, thus opening up new areas in the fields of drug release and target-fishing applications. This click-and-release technology offers the possibility of exchanging tags on proteins for functionalized cyclooctynes under mild and bioorthogonal conditions.

An integrated catalytic decarboxylation/carboxylation for accessing isotopically labeled carboxylic acids with 13CO2 or 14CO2 is described. The method shows a wide scope under mild conditions, even in the context of late-stage functionalization, and does not require stoichiometric organometallics, thus complementing existing carbon-labeling techniques en route to carboxylic acids.

Examples of organometallic compounds as nucleoside analogues are rare within the field of medicinal bioorganometallic chemistry. We report on the synthesis and properties of two chiral ferrocene derivatives containing a nucleobase and a hydroxyalkyl group. These so-called ferronucleosides show promising anticancer activity, with cytostatic studies on five different cancer cell lines indicating that both functional groups are required for optimal activity.

The reactivity of functionalized ynamides and arylynamines with tetracyanoethylene at room temperature was evaluated. In most cases, the corresponding 1,1,4,4-tetracyanobutadienes (TCBDs) were obtained in good to excellent yields through a [2+2]-cycloaddition/[2+2]-retro-electrocyclization sequence. The influence of diverse functional groups on the yield of the reaction was investigated, in particular concerning multiple ynamides. These TCBDs were characterized by various spectroscopic techniques and electrochemistry and X-ray diffraction in some cases.

The design, synthesis and electrochemical behaviour of an oligomer consisting of linked thymine-functionalised ferrocene units are reported, which, as a so-called form of ferrocene nucleic acid (FcNA), acts as a structural mimic of DNA.

Carbon isotope labeling is a traceless technology, which allows tracking the fate of organic compounds either in the environment or in living organisms. This article reports on a general approach...

A photocatalytic approach for carbon isotope exchange is reported. Utilizing [ 13 C]CO 2 and [ 14 C]CO 2 as primary C1 sources, this protocol allows the insertion of the desired carbon isotope into phenyl acetic acids without the need for structural modifications or prefunctionalization in one single step. The exceptionally mild conditions required for this traceless transformation are in stark contrast with those for previous methods requiring the use of harsh thermal conditions.

A general procedure for the late-stage [11C], [13C] and [14C]carbon isotope labeling of cyclic carbamates is reported. This protocol allows the incorporation of carbon dioxide, the primary source of carbon-14...