The present invention relates to compounds of the formula: ##STR1## and the pharmaceutically acceptable salts thereof, wherein Z can be: ##STR2## wherein R.sup.3 is alkyl having 1 to 6 carbon atoms and, when n is greater than 1, each R.sup.3 can be the same or different; and n is an integer from 1 to 3;R.sup.1 and R.sup.2 can each independently be hydrogen, straight or branched chain alkyl, or cycloalkyl having 3 to 8 carbon atoms which can optionally be substituted at one or more positions by alkyl of 1 to 6 carbon atoms; X is oxygen, sulfur, NR.sup.4, wherein R.sup.4 is hydrogen or alkyl having 1 to 4 carbon atoms, C.dbd.O, CHOH, or CH.sub.2 ; Y is hydrogen, alkoxy, halogen, alkyl, or hydroxy; and m is an integer from 0 to 3. The compounds are antagonists of platlet-activating factor (PAF).