The present invention relates to agents and compositions for the modification of the growth of bacterial cells. Thus, the compounds of the present invention are useful for the prevention and/or treatment of a disease in a subject. In particular, the present invention relates to the field of repurposing pharmaceutical compounds for treatment strategies of infectious diseases, gastrointestinal disorders, inflammatory diseases, proliferative diseases, metabolic disorders, cardiovascular diseases, and immunological diseases. Some of the compounds of the present invention demonstrate high specificity in inhibiting the growth of single bacterial species. Such compounds enable narrow-spectrum antibacterial therapies, constituting a major effort of current and future drug development strategies in order to reduce side effects of antibacterial treatment plans. Particularly interesting compounds of this invention are effective against pathobiological species such as Clostridium difficile, Clostridium perfingens, Fusobacterium nucleatum, and an enterotoxigenic strain of Bacteroides fragilis. Other compounds of the present invention reveal a strong inhibitory effect on a broad spectrum of bacterial species. Such compounds are useful for broad-spectrum antibiotic therapies of infections with unknown causative infecting bacterial species. Both types of compounds, especially the ones with narrow-spectrum antibacterialactivity, can further be used for modulating the microbiome composition and targeting species associated with dysbiosis and disease.