Trimers n-alkylglycine that can protect neurons against excitotoxic aggressions and compositions containing such trimers.

Trimers of N-alkylglycines (I), wherein R1, R2 and R3, independently, are selected from cyclopropyl, sec-butyl, 2- methoxyethyl, 3-methylbutyl, cyclohexyl, 2- (N-pyrrolidinyl) ethyl, 2 - (methylcarbonylamino) ethyl, 3- (2-oxo-N-pyrrolidinyl) propyl, 2- (2-pyridyl) ethyl, 2-phenylethyl, 1- (2-tetrahydrofuryl) methyl, 2- (N-imidazolyl) ethyl, 2- (4-methoxyphenyl) ethyl, 2- (3,4-dimethoxyphenyl) ethyl, 2- (2,4- dichlorophenyl) ethyl, 2- [2-N-methyl) pyrrolidinyl] ethyl, 2- (4-aminosulfonylphenyl) ethyl , 2- (morpholino) ethyl, 3-N, n, diethylamino) propyl, 3,3-diphenyl-propyl, 3- (N, N-dimethylamino) propyl, and 2- (N, N-diethylamino) ethyl its stereoisomeric forms and mixtures thereof, are able to block the L-glutamoto receptors, and are suitable for treating disorders such receptors mediate (I).