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Updated: Feb 26, 2026

Sequence-specific and Selective Recognition of Double-stranded RNAs over Single-stranded RNAs by Chemically Modified Peptide Nucleic Acids
Published on: September 21, 2017
Platinum(II) and palladium(II) complexes of tridentate hydrazone-based ligands as selective guanine quadruplex
Alexander Schmidt1, Rweetuparna Guha1, Alexander Hepp1
1Westfälische Wilhelms-Universität Münster, Institut für Anorganische und Analytische Chemie, Corrensstraße 28/30, 48149 Münster, Germany.
Abstract:
Several tridentate hydrazone-based ligands, synthesized by a condensation reaction of either 2-(1-methylhydrazinyl)pyridine or 2-(1-methylhydrazinyl)quinoline with an aldehyde (picolinaldehyde, 1H-pyrrole-2-carbaldehyde, 2-mercaptobenzaldehyde, 2-aminobenzaldehyde) have been reacted with palladium(II) and platinum(II) salts and precursor complexes to yield nine new metal complexes. These planar complexes were investigated with respect to their capability to interact with guanine quadruplex DNA. Two sequences (H-telo, derived from the human telomeric sequence, and c-myc, representing an excerpt of the promoter region of the c-Myc oncogene) were investigated. Circular dichroism (CD) spectroscopy, temperature-dependent CD spectroscopy, UV-Vis spectroscopy and a fluorescent intercalator displacement (FID) assay were applied in this respect. The spectroscopic data show that the complexes indeed interact with guanine quadruplex DNA. According to the FID assay, some of the complexes belong to the highest-affinity metal-containing quadruplex binders reported so far. Their affinity towards quadruplex DNA is up to 80-fold higher than to a reference double helix. These findings make the metal complexes good candidates as anticancer drugs, as guanine quadruplexes have been proposed as potential targets in anticancer drug design.
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