Compounds of the formula: ##STR1## wherein R.sup.1 is a higher alkyl group which may be substituted; R.sup.2 is a hydrogen, a lower alkyl group which may be substituted, a lower alkanoyl group which may be substituted or a lower alkylthiocarbamoyl group; R.sup.3 is a primary to tertiary amino group or a quaternary ammonium group; and n is 2 or 3, and salts thereof, have antitumor activity and platelet activating factor inhibitory activity.