For several years we have been investigating new anti-microbials that have novel modes of action. Four main compound-types have been explored: - Tetrahydroisoquinolines are an important set of compounds with a range of bioactivities. We have identified several of these alkaloids with anti-TB properties with a collaborator Prof S. Bahkta, and synthesised a range of compounds for anti-microbial screening with a view to probing the modes of action. Moreover we are also investigating anti-plasmodic and anti-viral properties of compounds. - The repurposing of existing drugs such as NSAID may be a valuable approach to TB-chemotherapeutics. With a collaborator Prof S. Bahkta (Birkbeck) we are exploring the SAR of a group of NSAIDs to identify compounds with enhanced bioactivities. - A new route to 1,3,5-N-alkyl pyridiniums was identified using phosphate-based media and with a collaborator Prof J. M. Ward we have established that the pyridiniums have interesting Gram-positive anti-bacterial properties. - Previously we have investigated the synthesis and biological activity of a series of calixarenes and novel small molecule analogues with anti-TB activities which appear to act via a novel host macrophage mediated mechanism.