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Your search keyword '"Kazazić, Snježana"' showing total 3 results
Start Over Author "Kazazić, Snježana" Topic esi-ms Publication Year Range Last 10 years
3 results on '"Kazazić, Snježana"'

2. ESI-MS studies of the non-covalent interactions between biologically important metal ions and N-sulfonylcytosine derivatives

Author

Ključarić, Valentina, Kobetić, Renata, Rinkovec, Jasmina, Kazazić, Snježana, Gembarovski, Dubravka, Saftić, Dijana, Matić, Josipa, Ban, Željka, and Žinić, Biserka

Subjects
NATURAL SCIENCES, Chemistry, Analytic Chemistry, Organic Chemistry, N-1-sulfonylcytosine derivatives, Cu(II) complexes, metal ions Na+, K+, Ca2+, Mg2+, Zn2+, non-covalent interactions, ESI-MS
Abstract

The aim of this report is to present the electrospray ionization mass spectrometry results of the non-covalent interaction of two biologically active ligands, N-1-(p-toluenesulfonyl)cytosine, 1-TsC, 1 and N-1 methanesulfonylcytosine, 1-MsC, 2 and their Cu(II) complexes Cu(1-TsCN3)2Cl2, 3 and Cu(1-MsC-N3)2Cl2 and 4 with biologically important cations: Na+, K+, Ca2+, Mg2+ and Zn2+. The formation of various complex metal ions was observed. The alkali metals Na+ and K+ formed clusters because of electrostatic interactions. Ca2+ andMg2+ salts produced the tris ligand andmixed ligand complexes. The interaction of Zn2+ with 1–4 produced monometal and dimetal Zn2+ complexes as a result of the affinity of Zn2+ ions toward both O and N atoms.

Published
2016

3. The transformation from 2°-amine to 3°-amine of cyclam ring alters the fragmentation patterns of 1-tosylcytosine-cyclam conjugates.

Author

Kobetić, Renata, Ključarić, Valentina, Saftić, Dijana, Matić, Josipa, Ban, Željka, Kazazić, Snježana, and Žinić, Biserka

Subjects
AMINES, CYTOSINE derivatives, ELECTROSPRAY ionization mass spectrometry, COMPLEXATION reactions, METAL complexes
Abstract

The novel N-1-sulfonylcytosine-cyclam conjugates 1 and 2 conjugates are ionized by electrospray ionization mass spectrometry (ESI MS) in positive and negative modes (ES+ and ES-) as singly protonated/deprotonated species or as singly or doubly charged metal complexes. Their structure and fragmentation behavior is examined by collision induced experiments. It was observed that the structure of the conjugate dictated the mode of the ionization: 1 was analyzed in ES- mode while 2 in positive mode. Complexation with metal ions did not have the influence on the ionization mode. Zn2+ and Cu2+ complexes with ligand 1 followed the similar fragmentation pattern in negative ionization mode. The transformation from 2°-amine in 1 to 3°-amine of cyclam ring in 2 leads to the different fragmentation patterns due to the modification of the protonation priority which changed the fragmentation channels within the conjugate itself. Cu2+ ions formed complexes practically immediately, and the priority had the cyclam portion of the ligand 2. The structure of the formed Zn2+ complexes with ligand 2 depended on the number of 3° amines within the cyclam portion of the conjugate and the ratio of the metal:ligand used. The cleavage of the cyclam ring of metal complexes is driven by the formation of the fragment that suited the coordinating demand of the metal ions and the collision energy applied. Finally, it was shown that the structure of the cyclam conjugate dictates the fragmentation reactions and not the metal ions. [ABSTRACT FROM AUTHOR]

Published
2018
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