The antitumor activity of the organometallic ruthenium(II)-arene complexes, RuCl(2)(eta(6)-arene)(PTA), (arene = p-cymene, toluene, benzene, benzo-15-crown-5, 1-ethylbenzene-2,3-dimethylimidazolium tetrafluoroborate, ethyl benzoate, hexamethylbenzene; PTA = 1,3,5-triaza-7-phosphaadamantane), abbreviated RAPTA, has been evaluated. In vitro biological experiments demonstrate that these compounds are active toward the TS/A mouse adenocarcinoma cancer cell line whereas cytotoxicity on the HBL-100 human mammary (nontumor) cell line was not observed at concentrations up to 0.3 mM, which indicates selectivity of these ruthenium(II)-arene complexes to cancer cells. Analogues of the RAPTA compounds, in which the PTA ligand is methylated, have also been prepared, and these prove to be cytotoxic toward both cell lines. RAPTA-C and the benzene analogue RAPTA-B were selected for in vivo experiments to evaluate their anticancer and antimetastatic activity. The results show that these complexes can reduce the growth of lung metastases in CBA mice bearing the MCa mammary carcinoma in the absence of a corresponding action at the site of primary tumor growth. Pharmacokinetic studies of RAPTA-C indicate that ruthenium is rapidly lost from the organs and the bloodstream.

Hydrogen gas is a storable form of chemical energy that could complement intermittent renewable energy conversion. One of the main disadvantages of hydrogen gas arises from its low density, and therefore, efficient handling and storage methods are key factors that need to be addressed to realize a hydrogen-based economy. Storage systems based on liquids, in particular, formic acid and alcohols, are highly attractive hydrogen carriers as they can be made from CO or other renewable materials, they can be used in stationary power storage units such as hydrogen filling stations, and they can be used directly as transportation fuels. However, to bring about a paradigm change in our energy infrastructure, efficient catalytic processes that release the hydrogen from these molecules, as well as catalysts that regenerate these molecules from CO and hydrogen, are required. In this review, we describe the considerable progress that has been made in homogeneous catalysis for these critical reactions, namely, the hydrogenation of CO to formic acid and methanol and the reverse dehydrogenation reactions. The dehydrogenation of higher alcohols available from renewable feedstocks is also described. Key structural features of the catalysts are analyzed, as is the role of additives, which are required in many systems. Particular attention is paid to advances in sustainable catalytic processes, especially to additive-free processes and catalysts based on Earth-abundant metal ions. Mechanistic information is also presented, and it is hoped that this review not only provides an account of the state of the art in the field but also offers insights into how superior catalytic systems can be obtained in the future.

The promising drug candidate indazolium trans-[tetrachlorobis(1H-indazole)ruthenate(III)] (KP1019) is the second Ru-based anticancer agent to enter clinical trials. In this review, which is an update of a paper from 2006 (Hartinger et al., J. Inorg. Biochem. 2006, 100, 891-904), the experimental evidence for the proposed mode of action of this coordination compound is discussed, including transport into the cell via the transferrin cycle and activation by reduction. The results of the early clinical development of KP1019 are summarized in which five out of six evaluated patients experienced disease stabilization with no severe side effects.

In undergraduate level organometallic chemistry courses students are usually taught that organometallic compounds are toxic and unstable in air and water. While this is true of many complexes, some are also non-toxic and stable in air and water. Indeed, bioorganometallic chemistry, the study of biomolecules or biologically active molecules that contain at least one carbon directly bound to a metal, is a thriving subject, and air and water stability is a general pre-requisite. This interdisciplinary field is located at the borderline between chemistry, biochemistry, biology and medicine. In this tutorial review, various aspects of bioorganometallic chemistry are introduced, with the main emphasis on medicinal organometallic compounds. Organometallic therapeutics for cancer, HIV and malaria and other medicinal applications are described. It is also shown how rational ligand design has led to new improved therapies much in the same way that an organometallic chemist working in catalysis will design new ligands for improved activities.

The discovery of new metal-based antitumour drugs, whether cisplatin derivatives or those based on other metals, has been largely based on cell viability assays (IC50 values) and compounds that bind to DNA. This approach has been applied for more than 30 years during which time very few new drugs have entered clinical use. In this article we discuss what the future holds for metal-based drugs, in particular anti-metastasis drugs, in these enlightened times of the post genomic era.