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

Abstract

<jats:p>Three new platinum(II) complexes bearing a eugenol and a pyridine derivative, namely (η<jats:sup>2</jats:sup>-2-allyl-4-methoxy-5-{[(propan-2-yloxy)carbonyl]methoxy}phenyl-κ<jats:italic>C</jats:italic> <jats:sup>1</jats:sup>)chlorido(pyridine-κ<jats:italic>N</jats:italic>)platinum(II), [Pt(C<jats:sub>15</jats:sub>H<jats:sub>19</jats:sub>O<jats:sub>4</jats:sub>)Cl(C<jats:sub>5</jats:sub>H<jats:sub>5</jats:sub>N)], (<jats:bold>I</jats:bold>), (η<jats:sup>2</jats:sup>-2-allyl-4-methoxy-5-{[(propan-2-yloxy)carbonyl]methoxy}phenyl-κ<jats:italic>C</jats:italic> <jats:sup>1</jats:sup>)chlorido(4-methylpyridine-κ<jats:italic>N</jats:italic>)platinum(II), [Pt(C<jats:sub>15</jats:sub>H<jats:sub>19</jats:sub>O<jats:sub>4</jats:sub>)Cl(C<jats:sub>6</jats:sub>H<jats:sub>7</jats:sub>N)], (<jats:bold>II</jats:bold>), and (η<jats:sup>2</jats:sup>-2-allyl-4-methoxy-5-{[(propan-2-yloxy)carbonyl]methoxy}phenyl-κ<jats:italic>C</jats:italic> <jats:sup>1</jats:sup>)chlorido(pyridine-4-carboxylic acid-κ<jats:italic>N</jats:italic>)platinum(II), [Pt(C<jats:sub>15</jats:sub>H<jats:sub>19</jats:sub>O<jats:sub>4</jats:sub>)Cl(C<jats:sub>6</jats:sub>H<jats:sub>5</jats:sub>NO<jats:sub>2</jats:sub>)], (<jats:bold>III</jats:bold>), have been synthesized and further characterized by single-crystal X-ray diffraction. The Pt<jats:sup>II</jats:sup> 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 <jats:italic>cis</jats:italic> position with respect to the double bond. Complexes (<jats:bold>I</jats:bold>) and (<jats:bold>II</jats:bold>) crystallize isomorphously in space group <jats:italic>P</jats:italic>\overline{1} and display a similar crystal packing characterized by C—H...O hydrogen bonding, C—H...π and π–π interactions. However, the presence of the additional methyl group in the 4-methylpyridine ligand in (<jats:bold>II</jats:bold>) disturbs the π–π interactions. The crystal packing of (<jats:bold>III</jats:bold>) is characterized by O—H...O hydrogen bonding, resulting in the formation of chains of molecules connected in a head-to-tail fashion and running in the [101] direction. The IC<jats:sub>50</jats:sub> values for the HepG2 and KB cell lines are 150.9, 122.3 µ<jats:italic>M</jats:italic> for (<jats:bold>I</jats:bold>) and 138.9, 93.2 µ<jats:italic>M</jats:italic> for (<jats:bold>II</jats:bold>), respectively.</jats:p>

Mixed Arylolefin/NHC Complexes of Platinum(II): Syntheses, Characterizations, and In Vitro Cytotoxicities

“…Differences in growth rates, drug sensitivities, and other factors of different cell lines may have influenced the variations in the cells . Numerous reports have also illustrated that the reported IC 50 values of NHC/arylolefin Pt­(II) complexes may vary among the different cell lines tested. ,,,, …”