Organometallic pharmaceutical

Fish RH, Jaouen G (2003) Bioorganometallic chemistry structural diversity of organometallic complexes with bioligands and molecular recognition studies of several supramolecu-lar hosts with biomolecules, alkali-metal ions, and organometallic pharmaceuticals. Organometallics 22 2166-2177... 

More recently, the Tc(I) compound [Tc(C0)3(H20)3]+ has become an important starting material for labeling organometallic pharmaceuticals. The compound can be prepared in water and at normal pressure. The use of the toxic gaseous CO was a problem, but a kit has recently been developed using solid nontoxic potassium boranocarbonate, which releases CO when hydrolyzed and which can reduce Tc(VII) to Tc(I). Therefore this kit should increase drastically the use of the precursor [Tc(C0)3(H20)3]+ for Tc and Tc studies. The chemistry of this molecule will be discussed in more details in a later section. 

Here we will recall just two of the advances made in the field of radiopharmaceuticals over the last few years. One shining example of an organometallic pharmaceutical that has been successfully commercialized is technetium-99m sestamibi, a hexakis (aUcyhsocyanide) complex of Tc(I) 29 that has become the most important myocardial imaging agent. The success of this compound, known by its trade name Cardiohte , has inspired researchers to develop other Tc-based radiopharmaceuticals [193-197]. 

Supramolecular Host Recognition Processes with Biological Compounds, Organometallic Pharmaceuticals, and Alkali-metal Ions as Guests... 

High Sugars Vitamins Organometallics Pharmaceutical >Cs paraffins... 

It is likely that the few organometallic systems we currently recognize in biology represent a small fraction of the total, and that many others, including new organometallic pharmaceuticals, remain to be discovered. We can therefore anticipate growing interest in this new area. 

Indeed, these reactions proceed at 25 °C in ethanol-aqueous media in the absence of transition metal catalysts. The ease with which P-H bonds in primary phosphines can be converted to P-C bonds, as shown in Schemes 9 and 10, demonstrates the importance of primary phosphines in the design and development of novel organophosphorus compounds. In particular, functionalized hydroxymethyl phosphines have become ubiquitous in the development of water-soluble transition metal/organometallic compounds for potential applications in biphasic aqueous-organic catalysis and also in transition metal based pharmaceutical development [53-62]. Extensive investigations on the coordination chemistry of hydroxymethyl phosphines have demonstrated unique stereospe-cific and kinetic propensity of this class of water-soluble phosphines [53-62]. Representative examples outlined in Fig. 4, depict bidentate and multidentate coordination modes and the unique kinetic propensity to stabilize various oxidation states of metal centers, such as Re( V), Rh(III), Pt(II) and Au(I), in aqueous media [53 - 62]. Therefore, the importance of functionalized primary phosphines in the development of multidentate water-soluble phosphines cannot be overemphasized. 

TOF-SIMS has been employed for the characterization of a wide range of materials, including metallic, salt, organometallic, organic, and polymeric substances, as well as for electronics, catalysts, and forensic samples. The ability to image molecular ions with submicrometer spatial resolution makes TOF-SIMS well suited to analysis of pharmaceuticals and biological cells, as well as for use in biotechnology and molecular electronics. 

Makoto Yamashita Makoto Yamashita, born in 1974 in Hiroshima, received his Ph.D. from Hiroshima University in 2002 under the guidance of Professor Yohsuke Yamamoto and Professor Kin-ya Akiba. He spent two years as a JSPS research fellow under the supervision of Professor John F. Hartwig at Yale University and Professor Takayuki Kawashima at The University of Tokyo. He started his current appointment as a research associate with Professor Kyoko Nozaki at The University of Tokyo in 2004. His current research interests are organometallic chemistry, organome-tallic catalyst, polymer chemistry, and main group chemistry. He has been awarded Inoue Research Award for Young Scientist (2005) and Takeda Pharmaceutical Company Award in Synthetic Organic Chemistry, Japan (2005). 

The problems addressed by inorganic chemistry continue to be challenges well into the twenty-first century. For example, coordination chemistry will continue to provide compounds with unusual properties and uses, and will become an increasingly important component in bioinorganic chemistry. Organometallic chemistry will continue as one of the most active areas of catalysis research, especially in the chemical, energy, pharmaceuticals, and pollution control industries. New methods to meet the needs of the production of inorganic chemicals will involve environmental friendly synthesis (Navratil, 1998). 

The Bj2 vitamers consist of a group of organometallic compounds that have a common cor-rinoid structure and vary in the substituent bound to the central cobalt atom (Fig. 7) (167,168). The principal naturally occurring Bl2 vitamers are hydroxocobalamin (HOCbl), methylcobal-amin (MeCbl), and adenosylcobalamin (AdoCbl). Cyanocobalamin (CNCbl) is the form commonly used for clinical, pharmaceutical, and food fortification purposes, due to its greater relative stability. 

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