Crystal structures of three platinacyclic complexes bearing isopropyl eugenoxyacetate and pyridine derivatives.

Three new platinum(II) complexes bearing a eugenol and a pyridine derivative, namely (η(2)-2-allyl-4-meth-oxy-5-{[(propan-2-yl-oxy)carbon-yl]meth-oxy}phenyl-κC (1))chlorido-(pyridine-κN)platinum(II), [Pt(C(15)H(19)O(4))Cl(C(5)H(5)N)], (I), (η(2)-2-allyl-4-meth-oxy-5-{[(propan-2-yl-oxy)carbon-yl]meth-oxy}phenyl-κC (1))chlorido-(4-methyl-pyridine-κN)platinum(II), [Pt(C(15)H(19)O(4))Cl(C(6)H(7)N)], (II), and (η(2)-2-allyl-4-meth-oxy-5-{[(propan-2-yl-oxy)carbon-yl]meth-oxy}phenyl-κC (1))chlorido(pyridine-4-carb-oxy-lic acid-κN)platinum(II), [Pt(C(15)H(19)O(4))Cl(C(6)H(5)NO(2))], (III), have been synthesized and further characterized by single-crystal X-ray diffraction. The Pt(II) atoms exhibit the usual distorted square-planar coordination and are surrounded by one Cl atom, one N atom, and a C atom and C=C double bond of the eugenol ligand. The donor N atom of the pyridine ligand occupies a cis position with respect to the double bond. Complexes (I) and (II) crystallize isomorphously in space group P and display a similar crystal packing characterized by C-H⋯O hydrogen bonding, C-H⋯π and π-π inter-actions. However, the presence of the additional methyl group in the 4-methyl-pyridine ligand in (II) disturbs the π-π inter-actions. The crystal packing of (III) is characterized by O-H⋯O hydrogen bonding, resulting in the formation of chains of mol-ecules connected in a head-to-tail fashion and running in the [101] direction. The IC(50) values for the HepG2 and KB cell lines are 150.9, 122.3†µM for (I) and 138.9, 93.2†µM for (II), respectively.