Cyclam-based molybdenum carbonyl complexes as a novel class of cytotoxic agents

Abstract

Cyclam-based molybdenum carbonyl complexes of formulae [(H₂R₂Cyclam)Mo(CO)₃] (R = H, ^4-tBuPhCH₂, ^4-CF3PhCH₂ and ^3,5-MePhCH₂) were prepared in high yields by the reaction of Mo(CO)₆ with the appropriate ligand precursor under reflux in di-n-butyl ether. All complexes were characterized by elemental analysis, IR, UV-Vis and NMR spectroscopy, thermogravimetry as well as single-crystal X-ray diffraction in the case of [(H₄Cyclam)Mo(CO)₃]. The cytotoxic effect of all compounds was examined on the human breast cancer cells MCF-7 and MDA-MB-231 revealing high antiproliferative activity.