A compound of formula (I) or a pharmaceutically acceptable salt, ester or pro-drug thereof: wherein R1 is a substituent； R2 and R5 are hydrogen or alkyl； R3 and R4 are hydrogen or a substituent, or, taken together with the atoms to which they are attached, R1 and R2 or R1 and R3 form a heterocyclyl ring； R6 and R7 are hydrogen or a substituent, or, taken together with the carbon atom to which they are attached, R6 and R7 form a cycloalkyl or heterocyclyl ring； W represents (Aaa)n, wherein each Aaa is an independently selected amino acid； n is an integer of from 1 to 20. These compounds are inhibitors of rhomboid intramembrane proteases based on peptidyl ketoamides. The compounds, and pharmaceutical compositions containing them, can be used for the use in the treatment of e.g. malaria, Parkinsons disease, cancer, diabetes and bacterial infections.
