In the present paper we report the synthesis and structural IR and
1H and
13C NMR characterization offourplatinum(II) and palladium(II) cyclometalated complexes ofthe formula[Pd(4-ClC
6H
4N=C(COC
6H
5)C
6H
4)X]
2,where X = OAc (
2) or Cl (
3), and[Pt(4-ClC
6H
4N=C(COC
6H
5)C
6H
4)X]
2,where X = Cl (
4) or OAc (
5).Theacetate-bridged compounds
2 and
5 have anopen-book structure. The chloro-bridged compounds
3 and
4 havean unfolded structure. Complex
2 crystallizes in thecentrosymmetric triclinic space group
P![](/images/entities/onemacr.gif)
, with
Z = 2. Unitcell parameters are as follows:
a = 11.765(3) Å,
b = 12.862(4) Å,
c = 15.022(5) Å,
![](/images/gifchars/alpha.gif)
= 84.08(2)
![](/images/entities/deg.gif)
,
![](/images/gifchars/beta2.gif)
= 78.56(2)
![](/images/entities/deg.gif)
,
![](/images/gifchars/gamma.gif)
= 83.13(2)
![](/images/entities/deg.gif)
. All these compounds were screenedagainst MDA-MB 468 (breast carcinoma) and HL-60(leukemic) tumor cells. The low IC
50 values ofcompound
5 (1.05
![](/images/entities/mgr.gif)
M) and of compound
4 (1.58
![](/images/entities/mgr.gif)
M) againstMDA-MB 468 and of 0.82
![](/images/entities/mgr.gif)
M (
5) and 1.37
![](/images/entities/mgr.gif)
M (
4)against HL-60 relative to
cis-DDP (2.67 and 2.07
![](/images/entities/mgr.gif)
M,respectively) and other cyclometalated compounds suggest that thesynthesized compounds may be regarded ashaving potential antitumor properties. The data suggest that theantiproliferative activity of compound
5 maycorrelate with its covalent binding to DNA and the induction ofimportant modifications on the helix.