Self‐Assembled Supramolecular Hetero‐Bimetallacycles for Anticancer Potency by Intracellular Release

Abstract

Two new tetracationic hetero-bimetallacycles, 4 and 5, have been constructed from an N,N′-bis(4-(pyridin-4-ylethynyl)phenyl)pyridine-2,6-dicarboxamide ligand, 1, and cis-blocked complexes [M(dppf)](OTf)2 (dppf = 1,1′-bis(diphenylphosphino)ferrocene; M = Pd (2), Pt (3)) in CH3NO2/CH2Cl2 (1:1) solvent. Both complexes were isolated with adequate yields as triflate salts and were then characterized using 1H, 13C, and 31P NMR spectroscopy, elemental analysis, UV-Vis spectroscopy, and high-resolution electrospray mass spectrometry (HR-ESMS). The molecular structure of 4 was determined by molecular mechanics force field calculations. The cytotoxic effect of both new complexes were analyzed against T98G (brain tumor), KB (head and neck cancer), SNU-80 (thyroid cancer), and HEK-293 non-malignant cell lines. The cytotoxicity of complexes 4 and 5 were found to be considerably more effective against cancer cells than reference drug cisplatin. Annexin-V/PI staining, caspase-3/-7 activity, reduction in mitochondrial membrane potential justify a significant level of apoptosis in complex treated cells.

Mechanistic studies of the anticancer activity of an octahedral hexanuclear Pt(II) cage

“…12–16 More recent is work unveiling the in vitro and in vivo anticancer activity of Ru- and Pt-based supramolecules. 17–20 We and others have utilized metallocages to encapsulate and deliver biologically active small molecules to cancer cells. 21–26 Because the application of inorganic supramolecules in medicine is still in its infancy, fundamental studies aimed at improving our understanding of the biological properties of these complexes are of particular interest.…”

Ethylene Polymerization Using Site‐Selective Pyridine‐Amide Based Iron Complexes

“…The pyridine‐amide ligand‐based coordination complexes are extensively used for supramolecular structures . Such coordination complexes resulted in precise control over the placement of molecular components resulting in interesting structural topologies and tailor‐made properties …”

Self-assembled metal–organic polyhedra: An overview of various applications

“…Recently, the same group studied the cytotoxicity of hetero-bimetallic metallacycles (HBMCs), prepared by the [2+2] self-assembly of bis(4-(pyridine-4-ylethynyl)phenyl)pyridine-2,6-dicarboxamide (L7)and heterometallic cis-M-[(dppp)(OTf) 2 ] (M = Pd, Pt; dppp = 1,1-bis(diphenylphosphino)ferrocene; OTf = trifluoromethanesulfonate) (B6) against T98G (brain tumor), KB (head and neck cancer), SNU-80 (thyroid cancer), and HEK-293 non-malignant cell lines . These HBMCs were considerably more effective against cancer cells than reference drug cis-platin [106]. M a n u s c r i p t 13 …”