Interaction of organotin(IV) moieties with nucleic acid constituent: Synthesis, structural characterization and anti-inflammatory activity of tri-i-propyltin(IV) and diorganotin(IV) derivatives of guanosine

Abstract

Abstract Tri- i -propyltin(IV) and diorganotin(IV) derivatives of guanosine of the general formulae, i -Pr 3 Sn(HGuO).H 2 O and [R 2 Sn(O)(HGuO).H 2 O] n , where R = Me, n -Oct and Ph; H 2 GuO = Guanosine, have been synthesized by either sodium salt or azeotropic removal of water method. The bonding and coordination behavior in these derivatives are discussed on the basis of FT-IR, multinuclear 1 H, 13 C and 119 Sn NMR and 119 Sn Mossbauer spectroscopic studies. These investigations suggest that guanosine acts as monoanionic monodentate coordinating through O-2′ of the ribofuranose group. Diorganotin(IV) derivatives of guanosine have a polymeric structure with Sn O Sn bridges and cis -disposition of the organic groups in a distorted trigonal-bipyramidal geometry around the tin atom. 119 Sn Mossbauer and 119 Sn NMR spectral data of tri- i -propyltin(IV) derivative support a penta-coordinate distorted trigonal-bipyramidal structure having equatorial organic groups, and involving a water molecule and O-2′ of the ribofuranose group in the axial positions. Some extent of intermolecular hydrogen-bonding involving water or (OH) groups leading to some degree of polymerization could not be ignored. Tri- i -propyltin(IV) and diorganotin(IV) derivatives of guanosine exhibited very low anti-inflammatory activity (~ 7.51–9.21% inhibition) at 40 mg kg − 1 dose and LD 50 values > 200 mg kg − 1 in albino rats.