Abstract: The present invention provides compounds of the formula (III): ##STR1## or an acid addition salt thereof, wherein R.sup.6, R.sup.7, R.sup.9 and R.sup.10 are each hydrogen, halogen, C.sub.1-4 alkyl or trifluoromethyl and R.sup.8 is chlorine or R.sup.7 and R.sup.8 are linked to form a --CH.dbd.CH--CH.dbd.CH-- group when one of R.sup.6 and R.sup.10 is other than hydrogen provided that when R.sup.8 is chlorine R.sup.6, R.sup.7, R.sup.9 and R.sup.10 are not all hydrogen atoms and that any one of R.sup.6, R.sup.7, R.sup.9 and R.sup.10 is not chlorine when the other three groups are hydrogen. Also provided are pharmaceutical compositions containing compounds of the formula (III), the first medical use of compounds of the formula (III), a process for preparing such compounds and intermediates through which this process proceeds.

Abstract: The present invention provides compounds of the formula (III): ##STR1## or an acid addition salt thereof, wherein R.sup.6 is chlorine, bromine, iodine, C.sub.1-4 alkyl or trifluoromethyl, or R.sup.6 and R.sup.7 form a --CH.dbd.CH--CH.dbd.CH--group optionally substituted by a halogen atom or a C.sub.1-4 alkyl or trifluoromethyl group, R.sup.8 is hydrogen, bromine, iodine, C.sub.1-4 alkyl or trifluoromethyl, R.sup.9 is hydrogen, halogen, C.sub.1-4 alkyl or trifluoromethyl, R.sup.10 is hydrogen, methyl or fluorine and R.sup.11 is amino, C.sub.1-10 acylamino or di-substituted aminomethyleneamino provided that, at most, only two of R.sup.7 -R.sup.10 are other than hydrogen and that R.sup.7 -R.sup.10 are not all hydrogen when R.sup.6 is chlorine. Also provided are pharmaceutical compositions containing compounds of the formula (III), the first medical use of compounds of the formula (III), a process for preparing such compounds and intermediates through which this process proceeds.