(R)-isomers have affinity for the~-HT~ A receptor while the (5')-isomers have no such ability. The affinity of the@)-isomers was discussed on the basis of structure-activity relationships between the affinity and hydrophobicity of the (R)-isomers. Compounds 7 1 and 107, which are representative derivative compounds, have anticonflict activity and lessening of memory impairment. In particular, compound 107 cannot bind to receptors other than the~-HT~ A ...
