| abstract |
Oxa and thiaaliphatic bridged quinoxaline-2,3-diones of the general formula I wherein A₁ represents lower alkylidene or a group of the formula> CH-A₄-R₄ (Ia), A₂ is lower alkylidene or a group of the formulas> CH-A₄-R₄ (Ia),> C = O (Ib) or> CH (OH) -A₅-R₄ (Ic), A₃ oxy, optionally oxidized thio or a group> C (= O) (Ib means A₄ stands for lower alkylene, A₅ represents lower alkylene or a direct bond, n represents 0 or 1, R₁ and R₂ independently of one another are hydrogen, optionally substituted by lower alkyl and / or lower alkanoyl amino, nitro, lower alkanoyl, optionally etherified or esterified hydroxy, optionally esterified or amidated carboxy, cyano, optionally halogenated lower alkyl or halogen, R₃ is hydrogen or hydroxy and R₄ represents hydrogen, cyano, optionally esterified or amidated carboxy, optionally esterified phosphono or 5-tetrazolyl, and their pharmaceutically usable salts have antagonistic properties against excitatory amino acids and can be used as anticonvulsive and anti-neurodegenerative active pharmaceutical ingredients. |