Dataset Information

Structural Elucidation of Cisplatin and Hydrated cis-Diammineplatinum(II) Complex Conjugated with Cyanocobalamin by Liquid Chromatography with Electrospray Ionization-Mass Spectrometry and Multistage Mass Spectrometry.

ABSTRACT: Pt(II)-based derivatives bearing a cyanocobalamin (CNCbl) unit were synthesized in aqueous solutions, and the reaction mixtures were examined by reversed-phase liquid chromatography with electrospray ionization and linear ion trap mass spectrometry (MS). Isotopic pattern analysis, multistage mass-spectra (MS/MS and MS³) interpretation, and differential isotopic labeling were used to establish the chemical composition and to suggest the chemical structures of reaction products. When cisplatin (cis-[PtCl₂(NH₃)₂]) was used as a Pt(II) drug derivative, a coordination bond between diamminemonochloroplatinum(II) and the cyano group of CNCbl, in turn linked covalently to the vitamin Co(III) ion, occurred. The resulting conjugate with a Co^III-CN-Pt^II bridge was MS detected as a doubly positive charged ion with the prevailing isotopologue at m/z 810.26 (empirical formula [C₆₃H₉₅ClCo^IIIN₁₆O₁₄PPt]²⁺). Likewise, a peak signal centered at m/z 811.26 was observed when ¹⁵N-labeled cisplatin cis-[PtCl₂(¹⁵NH₃)₂] was used as Pt(II) complex, thus confirming the presence of both the cisplatin amino groups in the conjugate. A bifunctional conjugate was obtained between CNCbl and the cis-diamminediaquaplatinum(II), that is, cis-[Pt(NH₃)₂(H₂O)₂]²⁺; in this case, the planar coordination complex of Pt(II) was also involved in a covalent bond with the oxygen atom of one of the CNCbl amide moieties. The peak signal detected at m/z 792.26 (empirical formula [C₆₃H₉₄Co^IIIN₁₆O₁₄PPt]²⁺) changed to m/z 793.26 when the labeled cis-[Pt(¹⁵NH₃)₂(H₂O)₂]²⁺ complex was adopted for conjugation. Comparison between MS/MS spectra allowed an extended structural characterization of both conjugates, as such or ¹⁵N-labeled. Two-dimensional heteronuclear (¹H-¹⁵N) single quantum correlation NMR spectroscopy, applied to ¹⁵N-labeled conjugates, supported the hypotheses made on the Pt(II) coordination in both cases.

SUBMITTER: Ventura G

PROVIDER: S-EPMC6644602 | biostudies-literature | 2018 Oct

REPOSITORIES: biostudies-literature

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Publications

Structural Elucidation of Cisplatin and Hydrated <i>cis</i>-Diammineplatinum(II) Complex Conjugated with Cyanocobalamin by Liquid Chromatography with Electrospray Ionization-Mass Spectrometry and Multistage Mass Spectrometry.

Ventura Giovanni G Nardella Maria Incoronata MI Panella Andrea A Arnesano Fabio F Calvano Cosima Damiana CD Losito Ilario I Palmisano Francesco F Cataldi Tommaso R I TRI

ACS omega 20181009 10

Pt(II)-based derivatives bearing a cyanocobalamin (CNCbl) unit were synthesized in aqueous solutions, and the reaction mixtures were examined by reversed-phase liquid chromatography with electrospray ionization and linear ion trap mass spectrometry (MS). Isotopic pattern analysis, multistage mass-spectra (MS/MS and MS<sup>3</sup>) interpretation, and differential isotopic labeling were used to establish the chemical composition and to suggest the chemical structures of reaction products. When ci ...[more]

PMID: 31458014

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Dataset Information

Structural Elucidation of Cisplatin and Hydrated cis-Diammineplatinum(II) Complex Conjugated with Cyanocobalamin by Liquid Chromatography with Electrospray Ionization-Mass Spectrometry and Multistage Mass Spectrometry.

Publications

Structural Elucidation of Cisplatin and Hydrated <i>cis</i>-Diammineplatinum(II) Complex Conjugated with Cyanocobalamin by Liquid Chromatography with Electrospray Ionization-Mass Spectrometry and Multistage Mass Spectrometry.

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