Organometallic Iridium (III) Cyclopentadienyl Anticancer Complexes Containing C,N-Chelating Ligands

• Published in: Platinum metals review Vol. 56; no. 1; p. 54
• Main Authors: Liu, Z, Habtemariam, A, Pizarro, A M, Clarkson, G J, Sadler, P J
• Format: Journal Article
• Language: English
• Published: 01-01-2012
• Subjects: Aqueous solutions; Cancer; Human; Iridium; Ligands; Metalorganic compounds; Phenyls; Platinum metals
• ISSN: 0032-1400

[( eta super(5)-Cp super(x))Ir(C perpendicular )Cl] (Cp super(x) = Cp*, C perpendicular = 2-(p-tolyl)pyridine (1), 2-phenylquinoline (2), 2-(2,4-difluorophenyl)-pyridine (3); Cp super(x) = tetramethyl(phenyl)cyclopentadienyl (Cp super(xph)), C perpendicular = 2-phenylpyridine (4); and Cp super(x) = tetramethyl(biphenyl)cyclopentadienyl (Cp super(xbiph)), C perpendicular = 2-phenylpyridine (5)) have been synthesised and characterised. 2 and 5 have typical 'piano-stool' geometry. All the complexes hydrolysed rapidly in aqueous solution (<5 min). All the complexes showed potent cytotoxicity with IC sub(50) values from 6.5 to 0.7 mu M toward A2780 human ovarian cancer cells. Potency increased with additional phenyl substitution on Cp*: Cp super(xbiph) > Cp super(xph) > Cp*. Cp super(xbiph) with 5 exhibited submicromolar activity (twice as active as cisplatin).