| 摘要 |
<p>Compounds of formula (I), in which X represents a group (a), (b), (c) or (d) wherein R is hydrogen, C1-6 alkyl, phenyl or C7-12 phenalkyl, R1 and R2 each represent hydrogen or together represent an oxo group and R3, R4 and R5 each represent hydrogen or R1 represents hydrogen and two of R2, R3, R4 and R5 together represent the second bond of a double bond joining positions 7 and 8, 8 and 9 or 9 and 10 with the remaining two of R2, R3, R4 and R5 representing hydrogen, the compound optionally being in the form of a salt thereof formed with a physiologically acceptable inorganic or organic acid, are of value for the treatment of anxiety and in the improvement of learning ability and/or the reversal of amnesia.</p> |
