Abstract: The invention provides a compound of Formula (I) or a pharmaceutically acceptable salt; wherein L is a substituted or non-substituted aromatic ligand; Z is a halogen or coordinating ligand; M is a group 8 or group 9 transition metal selected from; Fe, Ru, Os, Co, Rh and Os; A and B are independently selected from a substituted or non-substituted indole or pyridine, may be the same or different and coordinate to the transition metal M through the nitrogen atom of the indole or pyridine. The compounds have been shown to have use against antibiotic-resistant bacteria. A further aspect of the invention is directed towards treating or preventing bacterial infections.