title: Mass spectrometry and UV-VIS spectrophotometry of ruthenium(II) [RuClCp(mPTA)2](OSO2CF3)2 complex in solution.
abstract: Ruthenium(II) complexes are of great interest as a new class of cancerostatics with advantages over classical platinum compounds including lower toxicity. The stability of the [RuClCp(mPTA)2](OSO2CF3)2 complex (I) (Cp cyclopentadienyl, mPTA N-methyl 1,3,5-triaza-7-phosphaadamantane) in aqueous solution was studied using spectrophotometry, matrix-assisted laser desorption/ionization (MALDI) and laser desorption/ionization (LDI) time-of-flight (TOF) mass spectrometry (MS). Spectrophotometry proves that at least three different reactions take place in water. Dissolution of I leads to fast coordination of water molecules to the Ru(II) cation and then slow hydrolysis and ligand exchange of chloride and mPTA with water, hydroxide or with trifluoromethane sulfonate itself. Via MALDI and LDI of the hydrolyzed solutions the formation of singly positively charged ions of general formula RuCl(p)(Cp)(q)(mPTA)(r)(H2O)(s)(OH)(t) (p = 0-1, q = 0-1, r = 0-2, s = 0-5, t = 0-2) and of some fragment ions was shown. The stoichiometry was determined by analyzing the isotopic envelopes and computer modelling. The [RuClCp(mPTA)2](OSO2CF3)2 complex can be stabilized in dilute hydrochloric acid or in neutral 0.15 M isotonic sodium chloride solution.
authors.affiliation: Department of Analytical Chemistry, Nutrition and Food Science, Faculty of Chemistry, University of La Laguna, Campus de Anchieta, 38071 La Laguna, Tenerife, Spain. empena@ull.es
authors.forename: Eladia María
authors.initials: EM
authors.lastname: Peña-Méndez
authors.forename: Beatriz
authors.initials: B
authors.lastname: González
authors.forename: Pablo
authors.initials: P
authors.lastname: Lorenzo
authors.forename: Antonio
authors.initials: A
authors.lastname: Romerosa
authors.forename: Josef
authors.initials: J
authors.lastname: Havel
mesh_terms: D000218:Adamantane / Q000031:analogs & derivatives* / Q000737:chemistry; D004355:Drug Stability; D009942:Organometallic Compounds / Q000737:chemistry*; D012428:Ruthenium / Q000737:chemistry*; D012995:Solubility; D019032:Spectrometry, Mass, Matrix-Assisted Laser Desorption-Ionization / Q000379:methods*; D013056:Spectrophotometry, Ultraviolet / Q000379:methods*
chemical_list: D009942:Organometallic Compounds; D012428:Ruthenium; D000218:Adamantane