New trimethyltin(IV) derivatives of dipeptides: synthesis, characteristic spectral studies and biological activity

Abstract

AbstractNew trimethyltin(IV) derivatives with general formulae Me3Sn(HL), where HL is the monoanion of glycyltyrosine (H2L‐1), glycylisoleucine (H2L‐2), leucylleucine (H2L‐3), leucyltyrosine (H2L‐4), alanylvaline (H2L‐5), and valylvaline (H2L‐6) have been synthesized by the reaction of Me3SnCl and the sodium salt of the respective dipeptide with filtration of the NaCl formed. The bonding and coordination behaviour in the compounds synthesized are discussed on the basis of IR and 119Sn Mössbauer spectroscopic studies in the solid state and multinuclear 1H, 13C and 117Sn magnetic resonance in solution. These investigations suggest that, in the solid state, all the ligands in Me3Sn(HL) act as monoanionic bidentates coordinating through the COO− and NH2 groups. The 119Sn Mössbauer studies indicate that, for these polymeric derivatives, the polyhedron around tin in Me3Sn(HL) is a trigonal‐bipyramid with the three methyl groups in the equatorial positions, while the axial positions are occupied by a carboxylic oxygen and the amino nitrogen atom from the adjacent molecule. The NMR data suggest that, in solution, an equilibrium between solvated and intramolecular coordinated monomeric species exists. The anti‐inflammatory and cardiovascular activities and toxicity of all these compounds have been determined. All the compounds have also been screened against Staphylococcus aureus Mau (29/58), S. aureus Mau (78/71), Bacillus subtilis (18/64), Escherichia coli (326/71), E. coli, Candida albicans (Pn‐10), Microsporum gypseum and Euglena gracillis. All the Me3Sn(IV) compounds exhibit good anti‐inflammatory activity. Me3Sn(GlyTyr) and Me3Sn(GlyIle) display a potent cardiovascular activity and Me3Sn(AlaVal) exhibits good antibacterial activity against all the strains chosen. Copyright © 2004 John Wiley & Sons, Ltd.