The present disclosure relates to compounds of formula (I) or a pharmaceutically acceptable salt thereof wherein R1 means a fluorine atom or a perhalogeno linear alkyl radical containing 1, 2 or 3 carbon atoms; R2 means a chlorine atom, a linear alkyl radical containing 1, 2 or 3 carbon atoms or a perhalogeno linear alkyl radical containing 1, 2 or 3 carbon atoms, and R means a hydrogen atom or a radical of formula (Ia). The present disclosure also relates to processes for their preparation as well their therapeutic uses, in particular such as for use in the treatment of malaria.