A series of pyrazolyl palladium(II), platinum(II) and gold(III) complexes, [PdCl2(3,5-R2bpza)] {R = H (1), R = Me (2), bpza = bis-pyrazolyl acetic acid}, [PtCl2(3,5-R2bpza)] {R = H (3a), R = Me (4)}, [AuCl2(3,5-
R2bpza)]Cl {R = H (5a), R = Me (6a)} and [PdCl2(3,5-R2bpzate)] {R = Me (7)} have been synthesised and
structurally characterised. Single crystal X-ray crystallography showed that the pyrazolyl ligands exhibit
N^N-coordination with the metals. Anticancer activities of six complexes 1–6a were investigated against
CHO cells and were found to have low activities. Substitution reactions of selected complexes 1, 2, 3a and
5a with L-cysteine show that the low anticancer activities compounds and that the rate of substitution
with sulfur-containing compounds is not the cause of the low anticancer activities.