Fused benzo compounds of formula I are provided, wherein A is a 2 to 6 membered hydrocarbon spacer group, B is a polar divalent group selected from a group (a); U is C, N or CH; X is a divalent 3-4 membered chain optionally comprising one or more heteroatoms; R.sup.1 is an aliphatic hydrocarbon group, arylalkyl or diphenylalkyl; R.sup.2 and R.sup.3 are hydrogen or alkyl or together form an ethylene or propylene bridge; R.sup.4, R.sup.5 and R.sup.6 are hydrogen or substituents; R.sup.7 and R.sup.8 are hydrogen or substituents including --COOR.sup.9 and --CONR.sup.10 R.sup.11 ; are 5-HT.sub.1A receptor ligands useful in the treatment of CNS disorders. Pharmaceutical compositions comprising the compounds and their use for the manufacture of a pharmaceutical preparation are also provided.