Glutamate receptor antagonists

A pharmaceutical composition comprising a compound of formula 1

• wherein
• X is a single bond,
• R1 is selected from the group consisting of
• hydrogen,
• halogen,
• nitro,
• unsubstituted lower alkyl or lower alkyl substituted by halogen,
• alkoxycarbonyl,
• unsubstituted lower cycloalkyl or cycloalkyl substituted with oxygen,
• unsubstituted benzoyl or benzoyl substituted with a substituent selected from the group consisting of lower alkyl, lower alkyl substituted by halogen and halogen,
• unsubstituted phenyl,
• phenyl substituted by a substituent selected from the group consisting of hydroxy, lower alkyl, lower alkyl substituted by halogen, lower cycloalkyl, lower alkoxy, lower alkoxy substituted by halogen and cyano,
• styrenyl,
• phenylethyl,
• napthyl,
• biphenyl,
• benzofuranyl,
• an unsubstituted 5- or 6-membered heterocyclic ring,
• a 5- or 6-membered heterocyclic ring substituted by a substituent selected from the group consisting of oxo, benzoyl, methanesulfonyl, benzenesulfonyl and acetyl;
• and
• R3 is selected from the group consisting of
• unsubstituted pyridine, unsubstituted thienyl and unsubstituted thiazolyl, or
• substituted pyridine, substituted thienyl and substituted thiazolyl, said substituted pyridine, said substituted thienyl or said substituted thiazoyl being substituted by a substitutent selected from the group consisting of
• halogen,
• cyano,
• nitro,
• azido,
• hydroxy,
• carboxy,
• morpholine-4-carbonyl,
• carbamoyl,
• thiocarbamoyl, N-hydroxycarbamoyl,
• trimethylsilyl-ethynyl,
• lower alkyl, lower alkynyl, lower alkoxy, halo-lower alkyl, 4-lower alkyl-piperazine-1-carbonyl, lower alkylaminocarbonyl, or
• lower alkyl, lower alkynyl, lower alkoxy, halo-lower alkyl, 4-lower alkyl-piperazine-1-carbonyl, lower alkylaminocarbonyl substituted by a substitutent selected from the group consisting of amino, lower alkylamino, acylamino, oxo, hydroxy;
• lower alkoxy, lower alkylthio, unsubstituted carboxy, esterified and amidated carboxy,
• an unsubstituted 5-membered aromatic heterocycle,
• a 5-membered aromatic heterocycle substituted by a substituent selected from the group consisting of
• amino,
• lower alkylamino,
• acylamino,
• oxo,
• hydroxy,
• lower alkoxy,
• lower alkylthio,
• carboxy,
• carboxy esterified with lower alkyl,
• carboxy amidated with lower alkylamino which is eventually substituted by hydroxy,
• lower alkyl,
• lower alkyl substituted by a substituent selected from the group consisting of halogen, hydroxy, amino, lower alkylamino, acylamino, amidino and amidino substituted by a substituent selected from the group consisting of
• lower alkyl,
• —C(NRR′)═NR″ wherein R, R′ and R″ are hydrogen or lower alkyl, hydroxy,
• lower alkoxy,
• lower alkylthio,
• acyloxy,
• lower alkylsulfinyl,
• lower alkylsulfonyl,
• lower alkoxy-lower alkylsulfanyl,
• lower alkylsulfanyl,
• cycloalkylsulfinyl,
• cycloalkylsulfonyl,
• hydroxyimino,
• lower alkoxyimino,
• lower alkoximino which is esterified or amidated,
• lower alkenyl,
• oxo,
• cyano,
• carbamoyloxy,
• sulfamoyl and
• sulfamoyl substituted by lower alkyl;
• and
• with the proviso that when X is a single bond and R3 is pyridinyl, R1 is not hydrogen or methyl, and a pharmaceutically acceptable excipient.