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Updated: Apr 4, 2026

Line Shape Analysis of Dynamic NMR Spectra for Characterizing Coordination Sphere Rearrangements at a Chiral Rhenium Polyhydride Complex
Published on: July 27, 2022
Synthesis and X-ray crystal structure of the dirhenium complex Re2(i-C3H7COO)4Cl2 and its interactions with the DNA
Alexander V Shtemenko1, Helen T Chifotides2, Dina E Yegorova1
1Department of Inorganic Chemistry, Ukrainian State University of Chemical Technology, Gagarin Ave. 8, Dnipropetrovs'k 49005, Ukraine.
Abstract:
The dirhenium complex Re2(i-C3H7COO)4Cl2 was synthesized and characterized by X-ray crystallography, (1)H NMR and electronic spectroscopies, and electrospray ionization-mass spectrometry. The reactions of Re2(i-C3H7COO)4Cl2 with the substituted DNA purine nucleobases guanine (9-methylguanine and 9-ethylguanine) and adenine (9-methyladenine and 9-ethyladenine) were investigated by proton nuclear magnetic resonance and electronic spectroscopies as well as electrospray ionization-mass spectrometry. The data corroborate binding of two 9-methylguanine (or 9-ethylguanine) and 9-methyladenine (or 9-ethyladenine) bases per dirhenium unit in a bidentate fashion, in equatorial positions, via sites N7/O6 and N1/N6, respectively, with concomitant substitution of two carboxylate groups to form a single isomer of cis-Re2(i-C3H7COO)2(nucleobase)2Cl2. The binding of the bases to the dirhenium core disrupts important nucleobase interactions and may have important biological implications with respect to the anticancer activity of dirhenium complexes.
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