Synthesis and characterization of and complexes

Synthesis, Structure, and Selective Cytotoxicity of Organometallic Cp*RuII O-Alkyl-N-phenylcarbamate Sandwich Complexes

Tetraphenylborate salts of the η6-arene Cp*RuII O-alkyl-N-phenyl carbamate organometallic sandwich complexes, [Cp*Ru(PhNHCO2R)]BPh4 for R = Me (1), Et (2), and n-Pr (3), have been prepared by a facile one-pot reaction between ruthenium trichloride, pentamethylcyclopentadiene, and phenylisocyanate in refluxing alcohol solutions, and have been characterized by Fourier-transform IR and NMR spectroscopy, electrospray mass spectrometry, and single-crystal X-ray structure determinations. In vitro cytotoxicity studies show the complexes to be potent growth inhibitors for a range of tumour cell lines, while expressing significantly lower levels of toxicity towards a normal human fibroblast cell line.

Novel organometallic cationic ruthenium(II) pentamethylcyclopentadienyl benzenesulfonamide complexes targeted to inhibit carbonic anhydrase

Cationic ruthenium(II) pentamethylcyclopentadienyl benzenesulfonamide sandwich complexes have been synthesized and screened for enzymatic inhibition of the physiologically dominant carbonic anhydrase (CA) isozymes: human CA I and II, mitochondrial isozymes VA and VB, and the cancer-associated isozyme IX. The complexes demonstrated weaker binding to CAs compared with typical aromatic sulfonamides, inhibiting the enzyme at high nanomolar concentrations. An in vitro cytotoxic evaluation of the complexes was also undertaken against a range of tumorigenic cell lines and a healthy human cell line. Complexes inhibited the growth of cancerous cells at low micromolar concentrations while expressing lower levels of toxicity towards the normal human cell line. Factors influencing the synthesis, cytotoxicity, and enzyme affinity for this series of organometallic complexes are discussed.