Two new supramolecular coordination complexes (SCCs), were obtained from the self-assembly of a new bis-benzimidazole bridged Ru acceptor, 4, with dipyridyl and tripyridyl donors, respectively. As part of a growing library of anticancer-active Ru-based SCCs, metalla-prism 6 selectively showed high cytotoxicities relative to cisplatin for a series of cancer cell lines, with IC50 values as low as 8.41 μM for MCF7 cells, as determined from MTS assays.