Platinum complexes agents

Sucralfate [54182-58-0] an aluminum salt of sucrose octasulfate, is used as an antacid and antiulcer medication (59). Bis- and tris-platinum complexes of sucrose show promise as antitumor agents (60). Sucrose monoesters are used in some pharmaceutical preparations (21). A sucrose polyester is under evaluation as a contrast agent for magnetic resonance imaging (mri) (61). Oral adrninistration of this substance opacifies the gastrointestinal tract and eliminates the need for purging prior to mri. 

The resistance of rhodium to chemical attack is remarkable, and surpasses that of platinum. Its domain of stability (as seen from Fig. 6.4) is extremely wide, and in the absence of complexing agents it is stable in aqueous solutions of all pH values. In the massive form it is unattacked by caustic alkalis, acids and oxidising agents, including aqua regia. When finely divided, however, it is attacked by concentrated sulphuric acid and aqua regia. 

Discussion. Iodine (or tri-iodide ion Ij" = I2 +1-) is readily generated with 100 per cent efficiency by the oxidation of iodide ion at a platinum anode, and can be used for the coulometric titration of antimony (III). The optimum pH is between 7.5 and 8.5, and a complexing agent (e.g. tartrate ion) must be present to prevent hydrolysis and precipitation of the antimony. In solutions more alkaline than pH of about 8.5, disproportionation of iodine to iodide and iodate(I) (hypoiodite) occurs. The reversible character of the iodine-iodide complex renders equivalence point detection easy by both potentiometric and amperometric techniques for macro titrations, the usual visual detection of the end point with starch is possible. 

The platinum complex (NH3)2PtCl2 is a well-known antitumor agent. Because the drug is soluble in water, it is readily excreted through the kidneys and can cause severe kidney damage. Various procedures are employed clinically to minimize these side effects, but the... 

Farrell, N. In Polynuclear Charged Platinum Complexes as a New Class of Anticancer Agents Kelland, L. R., Farrell, N., Eds. Humana Press Totowa, NJ,... 

The interaction of platinum(II) complexes with various amino acids and simple peptides is relevant to understanding the biological fate of platinum anticancer agents such as mplatin, and this area has been reviewed extensively.258-261... 

Cisplatin is a platinum complex (platinum dichloride and two ammonia molecules) used as a cytostatic agent against cancer. The molecule cross-links DNA strands, thus leading to cell death. 

The effects of the bifunctional Pt drugs are very like those of the cross-linking dialkylating agents known to be effective against cancer (90). The reader is reminded of the parallel chemistry of carbonium ions and of platinum complexes, section IIF. 

Schuster, M. Selective complexing agents for the trace enrichment of platinum metals. Fresenius J. Anal. Chem. 1992, 342, 791-794. 

PLATINUM COMPLEXES AS THERAPEUTIC AGENTS 9.18.2.1 Clinically Used Anticancer Agents. CA-platinum Compounds... 

Platinum complexes are cytotoxic agents yet the paradigm in cancer chemotherapy has moved to a more targeted approach, with special emphasis on signaling pathways. In this respect a remarkable story is that of arsenic trioxide, As203 (Trisenox, Cell Therapeutics Inc, Seattle, USA) which was approved by the FDA in September 2000 for treatment of acute promomyelo-cytic leukemia (APL) in patients who have relapsed or are refractory to retinoid and anthracycline chemotherapy. An estimated 1,500 new cases of APL are diagnosed yearly in the US, of which an... 

D. Cole-Hamilton, Liverpool University Professor Gray, some of the platinum complexes that you have prepared at the same time as producing hydrogen contain, formally at least, Pt(III). Can these compounds act as oxidising agents, either thermally or photochemically ... 

Platinum electrodes are widely used as an inert electrode in redox reactions because the metal is most stable in aqueous and nonaqueous solutions in the absence of complexing agents, as well as because of its electrocatalytic activity. The inertness of the metal does not mean that no surface layers are formed. The true doublelayer (ideal polarized electrode) behavior is limited to ca. 200-300 mV potential interval depending on the crystal structure and the actual state of the metal surface, while at low and high potentials, hydrogen and oxygen adsorption (oxide formation) respectively, occur. 

Platinum complexes (e.g., di-platinum, 8.100) are used as antineoplastic agents in the treatment of cancer. Their use is described in chapter 7. 

Ba[Pt(CN)4] is used in the production of fluorescent X-ray screens.94 Dichlorodihydroxy-diamine- and dichlorodinitratodiamine-platinum(IV) complexes show weak fungicidal activity, but there appears to be no likelihood of them actually being used to this end.95 Other applications of platinum complexes involve their use as anticancer agents, as selective stains in biology, in catalysis, in metallurgy and in photography, described in the relevant chapters of this volume. 

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