Inhibitors of NAALADase enzyme activity

A compound having the following formula:

• ##STR13## where R is hydrogen, C.sub.1 -C.sub.9 straight or branched chain alkyl or alkenyl group, C.sub.3 -C.sub.8 cycloalkyl, C.sub.3 or C.sub.5 cycloalkyl, C.sub.5 -C.sub.7 cycloalkenyl, or Ar.sub.1, wherein said alkyl, alkenyl, cycloalkyl, cycloalkenyl or aryl groups are optionally substituted with C.sub.3 -C.sub.8 cycloalkyl, C.sub.3 or C.sub.5 cycloalkyl, C.sub.5 -C.sub.7 cycloalkenyl, C.sub.1 -C.sub.4 alkyl, C.sub.1 -C.sub.4 alkenyl, hydroxy, halo, hydroxyl, nitro, trifluoromethyl, C.sub.1 -C.sub.6 straight or branched chain alkyl or alkenyl, C.sub.1 -C.sub.4 alkoxy, C.sub.1 -C.sub.4 alkenyloxy, phenoxy, benzyloxy, amino, or Ar.sub.1, and where Ar.sub.1 is selected from the group consisting of 1-naphthyl, 2-naphthyl, and phenyl, having one to three substituents which are independently selected from the group consisting of hydrogen, halo, hydroxyl, nitro, trifluoromethyl, C.sub.1 -C.sub.6 straight or branched alkyl or alkenyl, C.sub.1 -C.sub.4 alkoxy or C.sub.1 -C.sub.4 alkenyloxy, phenoxy, benzyloxy, and amino;
• or pharmaceutically acceptable salts or hydrates thereof.