Abstract: Compounds of formula ##STR1## wherein R.sub.1 is chloro, fluoro, bromo or trifluoromethyl;R.sub.2 is hydrogen, chloro , fluoro, bromo or trifluoromethyl;Z is CH or N;R.sub.3, R.sub.4 and R.sub.5, which are the same or different, are hydrogen or C.sub.1 -C.sub.4 alkyl, with the proviso that R.sub.4 is different from R.sub.5 when R.sub.3 is hydrogen;X is O, S, SO or SO.sub.2 ;R.sub.6 is a C.sub.1 -C.sub.5 polyfluoroalkyl group containing at least two fluorine atoms and optionally other halogen atoms selected from the group consisting of chloro and bromo; processes for their preparation and pharmaceutical compositions containing them are described.The compounds of formula II-A are endowed with a marked wide range antimycotic acitivity.