Abstract: A compound of Formula I ##STR1## or a pharmaceutically acceptable salt thereof wherein n is 1 or 2; R.sup.1 and R.sup.2 are independently H (provided only one is H at the same time), --OH, CN, CH.sub.2 CN, 2-- or 4--CF.sub.3, CH.sub.2 CF.sub.3, CH.sub.2 CHF.sub.2, CH.dbd.CF.sub.2, (CH.sub.2).sub.2 CF.sub.3, ethenyl, 2-propenyl, OSO.sub.2 CH.sub.3, OSO.sub.2 CF.sub.3, SSO.sub.2 CF.sub.3, COR, COOR, CON(R).sub.2, SO.sub.x CH.sub.3 (where, x is 0-2), SO.sub.x CF.sub.3, O(CH.sub.2).sub.x CF.sub.3, SO.sub.2 N(R).sub.2, CH.dbd.NOR, COCOOR, COCOON(R).sub.2, C.sub.1-8 alkyls, C.sub.3-8 cycloalkyls, CH.sub.2 OR, CH.sub.2 (R).sub.2, NRSO.sub.2 CF.sub.3, NO.sub.2, halogen, a phenyl at positions 2, 3 or 4, thienyl, furyl, pyrrole, oxazole, thiazole, N-pyrroline, triazole, tetrazole or pyridine; R.sup.3 is hydrogen, CF.sub.3, CH.sub.2 CF.sub.3, C.sub.1 -C.sub.8 alkyl, C.sub.3 -C.sub.8 cycloalkyl, C.sub.4 -C.sub.9 cycloalkyl-methyl, C.sub. 2 -C.sub.8 alkenyl, C.sub.2 -C.sub.