A compound having the formulaor a pharmaceutically acceptable salt thereof whereinR is hydrogen or hydroxy;R<1 >is hydrogen,alkyl,arylalkyl,(CH2)nOH, or(CH2)nNR<7>R<8>;R<5 >and R<6 >are each independentlyhydrogen,halogen,NO2,CN,CF3,SO2NR<7>R<8>,PO3R<9>R<10>,alkyl,alkenyl,alkynyl,(CH2)nCONR<7>R<8>,(CH2)nCO2R<10>,NHCOR<11>,A is a ring formed by the following:a-NR<12>-CHR<13>-CHR<14>-b,a-CHR<13>-CHR<14>-NR<12>-b,a-CHR<13>-NR<12>-CHR<14>-b,a-CHR<14>-CH2-NR<12>-CHR<13>-b,a-CHR<13>-NR<12>-CH2-CHR<14>-b,a-CH2-CH2-CHR<13>-NR<12>-b,a-NR<12>-CHR<13>-CHR<12>-CH2-CH2-b,a-CH2-CH2-NR<12>-CH2-CH2-b,a-CH2-CH2-CH2NR<12>-CH2-b,a-CH2-NR<12>-CH2-CH2-ba-CH2-CH2-CH2-CH2-NR<12>-b,a-NR<12>-CH2-CH2-CH2-CH2-b,The compounds are useful in the treatment of disorders responsive to the blockade of glutamic and aspartic acid receptors.