The present invention relates to novel labyrinthopeptin derivatives. These labyrinthopeptin derivatives are useful for the treatment of infectious diseases, such as an infectious disease caused by an infection with human respiratory syncytial virus (RSV), Kaposi sarcoma-associated herpesvirus (KSHV), cytomegalovirus (CMV/HCMV), dengue virus (DENV), chikungunya virus (CHIKV), tick-borne encephalitis virus (TBEV FSME virus), vesicular stomatitis Indiana virus (VSV), zika virus (ZIKV) and/or hepatitis C virus (HCV). Said labyrinthopeptin derivatives are also useful for analyzing the mode of action of labyrinthopeptins. Also encompassed by the present invention are labyrinthopeptins for use in treating an infectious disease, in particular an infectious disease caused by an infection with any one of the viruses selected from RSV, KSHV, CMV, CHIKV, TBEV, VSV, ZIKV and HCV. The invention further relates to a combination of labyrinthopeptin A1 and A2 for use as a medicament, e.g. for treating an infectious disease caused by an infection with RSV, KSHV, CMV, DENV, CHIKV, TBEV, VSV, ZIKV and/or HCV.
