Flexible and rigid ionic organoplatinum complexes and their antiproliferative activities

Syntheses of five (1–5) cationic organometallic complexes bearing two platinum (II) centers are being reported. Compounds 1 and 2 have a flexible molecular backbone and are isomeric. Compounds 3, 4, and 5 are structural isomers with a rigid structural framework and containing pyrimidine/pyrazine in the center and two pendant arms bearing the alkynyl–ditopic platinum units. Compounds 1–5 were systematically characterized using FT-IR, NMR [¹H, ³¹P{¹H}, and ¹³C{¹H}], and HRMS. The antiproliferative activity of these compounds was examined against HeLa cancer cell line, and results were compared with that of cisplatin. “Live/dead” cell death assay was performed to ratify the superior antiproliferative activities of some of these organometallic complexes with respect to cisplatin.