| 摘要 |
<p>TETRAPEPTIDEHYDRAZIDE DERIVATIVES Novel tetrapeptidehydrazide derivatives, inclusive of a pharmacologically acceptable acid addition salt thereof, which has the general formula (I): (I) ¢wherein R1 is hydrogen or lower alkyl; R2 is hydrogen or the side chain of a D-.alpha.-amino acid; R3 is hydrogen or lower alkyl; R4 is hydrogen, or a saturated or unsaturated and straight or branched lower aliphatic acyl group which may option-ally be substituted by hydroxy, amino, lower alkoxy, halogen, oxo, lower alkylthio or lower alkylthio oxide!, are useful as analgesics.</p> |
