The present invention relates to peptidomimetics of the formula (I) or (I)c wherein L1, L2, L3, R1, R2, R3, R4, R5, R6, n, m, Q, X, Z1 and Z2 are defined as mentioned in the description and to salts and solvates of each of these compounds and to processes for the preparation thereof, compositions containing them and the uses of such compounds. It has been found that the compounds have a high microbicide activity and are suited to combat resistant bacteria, such as meticillin-resistant Staphylococcus aureus (MRSA) strains, at very low concentrations.