| 摘要 |
<p>Compounds of formula (II): <CHEM> wherein n is 0, 1 or 2, R1, R2, R3 and R4 are each separately selected from hydrogen, unsubstituted acyclic aliphatic hydrocarbon groups having a maximum of six carbon atoms and C1-6 alkyl groups substituted by a hydroxy group or by a C1-6 alkoxy group, or one of R1 and R2 and one of R3 and R4 is hydrogen and the others together are a trimethylene, tetramethylene or pentamethylene bridging group, and R5 is a group such that under physiological conditions R5OH undergoes elimination with the formation of a 3,5-dioxopiperazinyl ring, but with the provisos that (a) when n = 0 the combinations R1 = R2 = R3 = R4 = H and R1 = R2 = R3 = H, R4 = methyl are excluded and (b) when n is 0, R1 and R3 are each hydrogen, and each of R2 and R4 is other than hydrogen the compound is in other than the meso or erythro configuration, and salts thereof formed with a physiologically acceptable inorganic or organic acid, are of use in therapy, particularly as cardioprotective agents.</p> |
