TRICYCLIC PYRIDONE DERIVATIVES

The novel pyridone derivatives of the formula I wherein Ra is hydrogen or halogen, Rb is -NR2R3 wherein R2 and R3 taken together with the nitrogen atom to which they are attached is a 1-azetidinyl, 1-pyrrolidinyl, 1-piperidinyl which is unsubstituted or mono- or disubstituted by lower alkyl, hydroxy, lower alkoxy, lower hydroxyalkyl, lower alkoxyalkyl or phenyl; B and the carbon atom denoted by alpha taken together is a group of the formula >C alpha -CR4=CH-CH=CH- and R4 is hydrogen, fluorine or chlorine, can be used for the control or prevention of illnesses. In particular, they have muscle relaxant, sedative-hypnotic, anxiolytic and/or anticonvulsive activity and can accordingly be used in the control or prevention of muscle tensions, stress conditions, insomnia, anxiety states and/or convulsions.