Supramolecular bidentate rhodium(I) or iridium(I) phosphine and oxazoline amino acid bioconjugates as selective catalysts for enantioselective reactions.

This publication describes monodentate phosphine and oxazoline ligands attached to an amino acid ester and the application of their supramolecularly assembled rhodium(I) or iridium(I) complexes in asymmetric catalysis. The major feature of these complexes is the transmission of chirality from distant hydrogen bonded amino acids to the prochiral catalytic metal center ("backdoor induction"). The generated homoleptic and heteroleptic rhodium(I) or iridium(I) precatalysts were studied by NMR, UV-VIS and CD spectroscopy as well as X-ray single crystal diffraction.

Dissimilar effect of organometallic ruthenium complexes on the viability of MDR and non-MDR experimental models.

Ruthenium complexes containing triphenylphosphine diamide ligands were prepared, characterized, and tested for their biological activity against various cancer cell lines and the malaria parasite, Plasmodium falciparum. The effect of M (mono-substituted) and B (bis-substituted) complexes on the human cervical carcinoma (HeLa) cell line was investigated using the MTT assay. Five (B2, B3, B5, B6, and B13) of the 24 synthesized ruthenium complexes showed significant effects with IC values ranging between 0.

Turn-on fluorescence of ruthenium pyrene complexes in response to bovine serum albumin.

Two novel pyrene triphenylphosphine ruthenium conjugates act as fluorescent turn-on beacons for serum albumin, being non-fluorescent in aqueous media but exhibiting strong emission upon binding to BSA. The selective cytotoxicity of the compounds against tumour cells is enhanced upon irradiation by UV-light, paving the way for application in photodynamic therapy under two-photon excitation.

A ferrocene-based pseudopeptide chiroptical switch.

We present a double-stranded ferrocene pseudopeptide 2b which exhibits stimuli responsive chirality inversion triggered by solvent exchange or acid addition. Compound 2b exists as a mixture of self-assembled fast exchanging oligomers which macroscopically behave as a chiroptical switch with two stable states. The ferrocene group inversion results in a distinct CD signal in the visible part of the spectrum.