0000000000658148
AUTHOR
Barbieri R.
The interaction of S,N-coordinated dimethyltin(IV) derivatives with deoxyribonucleic acid: Structure and dynamics by119Sn mössbauer spectroscopy
Complexes Me2SnCl(SPy) and Me2SnCl(SPym) (HSPy = 2-mercaptopyridine; HSPym = 2-mercaptopyrimidine), from ethanol solutions, interact with aqueous calf-thymus DNA yielding condensed phases with probable Me2Sn(SPy,-SPym) (DNA monomer) stoichiometries of 1:1; the condensation of DNA is inferred originated from electrostatic bonding between complex cations Me2Sn(SPy,SPym)+ and the phosphate oxygen of the phosphodiester groups. Octahedral-or trigonal-bipyramidal tin environments are inferred from the point-charge model treatment of the 119Sn Mössbauer parameter nuclear quadrupole splitting, considering the bonding by S and N, or only S donor atoms from the ligand, as well as possible coordinatio…
The interaction of deoxyribonucleic acid with methyltin(IV) moieties in solution studied by small-angle X-ray scattering, circular dichroism and UV spectroscopy
The nature of calf thymus DNA in aqueous solution, in the presence of the organotin(IV) species Sn(IV)Me3, Sn(IV)Me2 and Sn(IV)Me, possibly partly hydrolysed and/or hydrated, was investigated by small-angle X-ray scattering (SAXS), ultraviolet spectroscopy (UV) at different temperatures and circular dichroism (CD). The results are compared with those of previous 119Sn Mossbauer studies on condensed DNA phases. The effects of tin-phosphate oxygen bonding on the DNA melting profile in DNA-Sn(IV)Me systems are in agreement with previous reports on DNA-Main Group metal ion interactions. The structure and conformation of the DNA double helix are not influenced by Sn(IV)Me(n) species, even in exp…