Structural effects on the antitumour activity of a series of di(4‐substituted phenyl)tin dichloride complexes with nitrogen‐donor ligands

Investigation of the antitumour activity of a series of diorganotin dichloride complexes (4‐ZC 6 H 4 ) 2 SnCl 2 ·L 2 , where Z = OMe, Me, F, Cl, and CF 3 and L 2 = 2,2′‐bipyridyl (bipy), 1,10‐phenanthroline (phen) and 2‐aminomethylpyridine (amp) is reported. A number of these complexex are shown to exhibit reproducible activity in vivo towards P388 lymphocytic leukaemia in mice. 1 H NMR data are reported for an extended series of (4‐ZC 6 H 4 ) 4 Sn and the parent dichlorides (4‐ZC 6 H 4 ) 2 SnCl 2 of the above‐mentioned complexes. A correlation is reported between Hammett substituent constants and 1 H chemical shift data. Attempts are made to relate the antitumour activity of the complexes to various structural factors. The dependence of antitumour activity on the electronic effect of group Z and the nature of the ligand L 2 is demonstrated.