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Asymmetric Hydrogen Transfer Reactions Promoted by Homogeneous Transition Metal Catalysts
No full textCHEM. REV
Inhibitory effects of some organometallic complexes of rhodium(I) and iridium(I) on carrageenin paw edema in rats
No full textAntitumor action of rhodium(I) and iridium(I) complexes
No full textSeveral rhodium(I) and iridium(I) complexes displayed different degrees of antitumour activity when tested in mice bearing Ehrlich ascites carcinoma. Rhodium (I) and iridium (I) acetylacetonate derivatives caused a high percentage of cures. The rhodium (I) dimers were particularly interesting, since (bis(cycloocta-1,5-diene)micromicron' dichlorodirhodium(I) [RhCODCl]2) was highly effective, whereas its analogues, bis(bicyclo[2,2,1]hepta-2,5-diene)micromicron'-dichlorodirhodium(I) [RhNBDCl]2) and bis(1,5-hexadiene)micromicron' dichlorodirhodium(I) [RhEDCl]2) were virtually inactive. The absence of significant inhibition of DNA, RNA and protein syntheses in tumour cells found for [RhCODCl]2 at therapeutically active dosages, indicates that this substance has a different mechanism of action from that of cis-dichlorodiammine Pt(II) (cis-PDD). The amount of rhodium found in tumour cells after administration of active [RhCODCl]2 was higher than that for [RhEDCl]2, while the rhodium concentration in the ascitic fluid was much higher for [RhEDCl]2. A mechanism based on the chemical properties of the complexes is tentatively proposed for explaining these findings and selective toxicity for tumour cells
Antitumor effects of rhodium(I), iridium(I) and ruthenium(II) complexes in comparison with cis-dichloro-diamminoplatinum(II) in mice bearing Lewis lung carcinoma
No full textThe effects of square planar rhodium, [RhacacCOD]o and iridium, [IracacCOD]o complexes and of octahedral ruthenium, [cis-RuCl2 (DMSO)4]o complex have been examined in comparison with cis-dichlorodiammino platinum(II) (cis-PDD). The toxicity in BDF1 mice varies widely and decreasing LD50-values, ranging from 0.94 mg/kg to 1000 mg/kg, have been obtained for cis-PDD, [RhacacCOD]o, [IracacCOD]o and [cis-RuCl2(DMSO)4]o, respectively. All the tested complexes similarly inhibit the growth of subcutaneous Lewis lung carcinoma and the development of spontaneous as well as of artificial metastases, with the exception of [IracacCOD]o which is inactive on metastases. The antitumor activity of [RhacacCOD]o and [cis-RuCl2(DMSO)4]o appears interesting, since it is of the same magnitude as that of cis-PDD, considering also that they were found to be only marginally nephrotoxic
Antineoplastic activity and toxicity of an organometallic complex of ruthenium(II) in comparison with cis-PDD in mice bearing solid malignant neoplasms
No full textThe antineoplastic activity of an organometallic complex of ruthenium(II), [cis-RuCl2(DMSO)4]o, has been examined in comparison with that of cis-PDD, using three metastasizing tumors of the mouse: Lewis lung carcinoma, B16 melanoma and MCa mammary carcinoma. [cis-RuCl2(DMSO)4]o significantly reduces primary tumor growth in all the tumors tested, and its activity is similarly pronounced at three different dosages in mice bearing Lewis lung carcinoma. On the contrary, the survival time of animals having i.v. or i.m. tumor implants are only moderately increased, and also in the case of combined treatments with surgery. The antineoplastic activity of cis-PDD appears to be less pronounced than that of [cis-RuCl2(DMSO)4]o, and is limited to mice bearing B16 melanoma, which, among the three tumors used, appears to be naturally more responsive to cis-PDD and [cis-RuCl2(DMSO)4]o. The use of [cis-RuCl2(DMSO)4]o appears advantageous over that of cis-PDD since, unlike cis-PDD, its antineoplastic effects have been obtained at dosages with reduced host toxicity, indicated by the absence of significant hematological toxicity and toxicity for normal proliferating tissues
Antineoplastic Activity of planar Rhodium(I) complexes in mice bearing Lewis lung carcinoma and P388 leukemia
No full textEffects of two pyridinalalkyliminerhodium(I) complexes in mice bearing MCamammary carcinoma.
No full text
Coordination metal complexes of Rh(I), Ir(I) and Ru(II): recent advances on antimetastatic activity on solid mouse tumors
No full textFollowing pioneering observations on the mouse Ehrlich ascites carcinoma, the result of cooperation between the Institutes of Chemistry and Pharmacology of the University of Trieste, more recent studies have characterized some aspects of the antimetastatic properties of coordination metal complexes other than platinum compounds. The compounds examined, rhodium(I) and iridium(I) derivatives of the type [Mchel(LL)]+/o (chel= pyridinalimine (NNR), acetylacetonate; LL= 1,5-hexadiene, 1,5-cyclooctadiene, norbornadiene), both with a square-planar structure, and an octahedral ruthenium(II) derivative RuCl2(dimethylsulfoxide)4 were tested using the solid metastasizing tumor of the mouse, Lewis lung carcinoma. The conclusions which can be drawn from the resulting data concern the role of the metal, of the leaving group and of the non-leaving group as well. It was found that the organometallic complexes of Rh(I) are more active than those of Ir(I); within the Rh(I) derivatives of the type [Rh(I)COD(NNR)]+Cl- (RCH3, C2H5, iC3H7), the higher the hydrosolubility, the higher is the antitumor and particularly the antimetastatic effect; as far as the diolefinic ligands are concerned, the higher the chelating effect the higher are the antimetastatic properties of the resulting compound. Separate conclusions can be made for the Ru(II) derivative. Comparison of its antimetastatic effects with those of cis-dichlorodiammineplatinum(II) (cisplatin) using three solid mouse tumors, clearly shows a better therapeutic index for the former, suggesting that within this class of compounds it is conceivable to obtain derivatives with an antineoplastic activity comparable to or even higher than that of cisplatin
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