Electrospray ionization mass spectrometric study on the coordination behavior of dacarbazine towards transition metal ions

Dacarbazine

Dacarbazine is a cell cycle nonspecific antineoplastic alkylating agent used in the treatment of metastatic malignant melanoma. This chapter contains the descriptions of the drug: nomenclature, formulae, chemical structure, elemental composition, and appearance. The uses and applications of dacarbazine and the methods that were used for its preparation are reported. The methods which were used for the physical characterization of the drug are ionization constant, solubility, X-ray powder diffraction pattern, crystal structure, melting point, and differential scanning calorimetry. The profile contains the spectra of the drug: ultraviolet spectrum, vibrational spectrum, nuclear magnetic resonance spectra, and mass spectrum. The compendial methods of analysis for dacarbazine include the United States Pharmacopeia methods, British Pharmacopeia methods, and International Pharmacopeia methods. Other reported methods that are used for the analysis of the drug are high-performance liquid chromatography, high-performance liquid chromatography-mass spectrometry, and polarography. Metabolism, pharmacokinetics, and stability studies on dacarbazine are also included. Reviews of some analytical methods and physicochemical properties of the drug as well as the most important enzymes that are involved in the prodrug activation are provided. Sixty-four references are listed at the end of this monograph.

Structure−Activity Relationships for NAMI-A-type Complexes (HL)[trans-RuCl4L(S-dmso)ruthenate(III)] (L = Imidazole, Indazole, 1,2,4-Triazole, 4-Amino-1,2,4-triazole, and 1-Methyl-1,2,4-triazole): Aquation, Redox Properties, Protein Binding, and Antiproliferative Activity

Imidazolium [trans-tetrachloro(1H-imidazole)(S-dimethylsulfoxide)ruthenate(III)] (NAMI-A) and indazolium [trans-tetrachlorobis(1H-indazole)ruthenate(III)] (KP1019) are the most promising ruthenium complexes for anticancer chemotherapy. In this study, the azole ligand of NAMI-A was systematically varied (from imidazole of NAMI-A to indazole, 1,2,4-triazole, 4-amino-1,2,4-triazole, and 1-methyl-1,2,4-triazole), and the respective complexes were evaluated with regard to the rate of aquation and protein binding, redox potentials, and cytotoxicity by means of capillary zone electrophoresis, electrospray ionization mass spectrometry, cyclic voltammetry, and colorimetric microculture assays. Stability studies demonstrated low stability of the complexes at pH 7.4 and 37 degrees C and a high reactivity toward proteins (binding rate constants in the ranges of 0.02-0.34 and 0.01-0.26 min-1 for albumin and transferrin, respectively). The redox potentials (between 0.25 and 0.35 V) were found to be biologically accessible for activation of the complexes in the tumor, and the indazole-containing compound shows the highest antiproliferative activity in vitro.