title: Interactions of nucleosides with CrO(4) (2-) and Cr(3+) as studied by electrospray ionization mass spectrometry.
abstract: The interactions of CrO(4) (2-) and Cr(3+) with nucleosides studied by electrospray ionization mass spectrometry (ESI-MS) are reported. In water, the nucleosides which do not contain the NH(2) group form the unstable [M+HCrO(4)](-) anion. In the presence of a reducing agent, namely methanol, chromate anion forms stable complexes with nucleosides, [M+CH(3)CrO(4)](-) anions. The fragmentation of [M+CH(3)CrO(4)](-) anions involve elimination of the methanol molecule. Chromium cation-nucleoside complexes were not observed in water. In methanol solutions, adenosine and cytidine form [(M-H)+CrOCH(3)](+) and [(M-H)(2)+Cr](+) ions. Most probably, deprotonated imine tautomers form complexes in which a metal cation is simultaneously coordinated by two nitrogen atoms. Complexes containing chloride anions and a few methanol molecules were observed for other nucleosides. Guanosine and inosine form doubly charged ions of the type [M(2)+CrOCH(3)](2+) that probably contain a bond between the oxygen atom and the chromium cation, (HN(1)--C(6)==O)(2) (....)Cr(3+)).
authors.affiliation: Poznań University of Technology, Institute of Chemistry, Piotrowo 3, 60-965 Poznań, Poland. magdalena.franska@fct.put.poznan.pl
authors.forename: Magdalena
authors.initials: M
authors.lastname: Frańska
authors.forename: Karolina
authors.initials: K
authors.lastname: Gierczyk
mesh_terms: D000838:Anions; D002412:Cations; D002840:Chromates / Q000737:chemistry*; D002857:Chromium / Q000737:chemistry*; D015394:Molecular Structure; D009705:Nucleosides / Q000032:analysis / Q000737:chemistry*; D021241:Spectrometry, Mass, Electrospray Ionization / Q000379:methods*
chemical_list: D000838:Anions; D002412:Cations; D002840:Chromates; D009705:Nucleosides; D002857:Chromium