Use of 1,2,4-triazolo[1,5-a]pyrimidines to design new 'piano-stool' ruthenium(II) compounds

摘要

A series of neutral half-sandwich organometallic ruthenium(II) complexes of the general formula [(eta(6)-p-cym)Ru(L)Cl-2], where eta(6)-p-cym - p-cymene, was prepared by the direct reaction of a dichloride p-cymene ruthenium(II) dimer, [{(eta(6)-p-cym)Ru(mu-Cl)}(2)Cl-2], with corresponding 1,2,4-triazolo[1,5-a]pyrimidine ligands (L), namely, L-1,2,4-triazolo[1,5-a]pyrimidine (tp) (1), 5,7-dimethyl-1,2,4-triazolo [1,5-a]pyrimidine (dmtp) (2), 5,7-ditertbutyl-1,2,4-triazolo[1,5-a]pyrimidine (dbtp) (3), 7-isobutyl-5-methyl-1,2,4-triazolo[1,5-a]pyrimidine (ibmtp) (4), and 5,7-diphenyl-1,2,4-triazolo[1,5-a]pyrimidine (dptp) (5). The complexes were prepared in molar ratios of 1:2 (except (1), for which an excess of tp was used). The structures of the complexes were determined by multinuclear magnetic resonance (H-1, C-13, N-15) spectroscopy and X-ray diffraction. According to all the spectroscopic data, the molecules adopted the usual "piano-stool" geometry with a monodentate N3 triazolopyrimidine ligand. Studies on these lipophilic ruthenium(II) complexes revealed rather low in vitro antiproliferative activities against two human cell lines. (C) 2016 Elsevier Ltd. All rights reserved.