The present invention relates to benzoxazepine derivative having the general formula I, wherein X represents CO or SO.sub.2; R.sup.1, R.sup.2, R.sup.3 and R.sup.4 are independently selected from H, (C.sub.1-4)alkyl, (C.sub.1-4)alkyloxy, (C.sub.1-4)alkyloxy(C.sub.1-4)alkyl, halogen, nitro, cyano, NR.sup.8R.sup.9, NR.sup.8COR.sup.10, and CONR.sup.8R.sup.9, R.sup.5, R.sup.6 and R.sup.7 are independently H or (C.sub.1-4)alkyl; R.sup.8 and R.sup.9 are independently H or (C.sub.1-4)alkyl; or R.sup.8 and R.sup.9 form together with the nitrogen atom to which they are bound a 5- or 6-membered saturated heterocyclic ring, optionally containing a further heteroatom selected from O, S or NR.sup.11; R.sup.10 is (C.sub.1-4)alkyl; R.sup.11 is (C.sub.1-4)alkyl; A represents the residue of a 4-7 membered saturated heterocyclic ring, optionally containing an oxygen atom, the ring being optionally substituted with 1-3 substituents selected from (C.sub.1-4)alkyl, (C.sub.1-4)alkyloxy, hydroxy, halogen and oxo; or a pharmaceutically acceptable salt thereof. The invention also relates to pharmaceutical compositions comprising said derivatives, and to the use of these benzoxazepine derivatives in the treatment of neurological diseases and psychiatric disorders which are responsive to enhancement of synaptic responses mediated by AMPA receptors in the central nervous system ##STR00001##