Inhibition of cancer cell growth by ruthenium(II) cyclopentadienyl derivative complexes with heteroaromatic ligands

Inhibition of the growth of LoVo human colon adenocarcinoma and MiaPaCa pancreatic cancer cell lines by two new organometallic ruthenium(II) complexes of general formula [Ru(η5-C5H5)(PP) L][CF3SO3], where PP is 1,2-bis(diphenylphosphino)ethane and L is 1,3,5-triazine (Tzn) 1 or PP is 2x triphenylphosphine and L is pyridazine (Pyd) 2 has been investigated. Crystal structures of compounds 1 and 2 were determined by X-ray diffraction studies. Atomic force microscopy (AFM) images suggest different mechanisms of interaction with the plasmid pBR322 DNA; while the mode of binding of compound 1 could be intercalation between base pairs of DNA, compound 2 might be involved in a covalent bond formation with N from the purine base.