S⋅⋅⋅Sn Tetrel Bonds in the Activation of Peroxisome Proliferator-Activated Receptors (PPARs) by Organotin Molecules.

In this study, a PDB (Protein Data Bank) analysis and theoretical calculations (PBE0-D3/def2-TZVP level of theory) were combined to analyze the impact of S⋅⋅⋅Sn tetrel-bonding interactions in the activation mechanism of peroxisome proliferator-activated receptors (PPARs) by two organotin derivatives, triphenyltin (TPT) and tributyltin (TBT). The presence of a covalently bonded CYS285 to the organotin molecule was found to be key to enhance the σ-hole-donor ability of the tin atom, thus strengthening the tetrel-bonding interaction with a sulfur atom belonging to a vicinal methionine residue (MET364).