| 摘要 |
<p>NEW MATERIAL:The titled compound of formula I (X is Gly, Ala, Ser, etc.). EXAMPLE:L-Tyrosyl-glycyl-glycyl-L-phenylalaninol. USE:Useful as an analgesic, a narcotic antagonistic and an antidiarrheic drugs having an agonistic activity in the opiate acceptor and a prolonged duration with low toxicity, and including any of optical isomers and racemates. PROCESS:A dipeptide of formula II (R<3> is amino-protecting group; R<4> is carboxyl- protecting group) is reacted with a dipeptide of formula III by the conventional peptide linkage forming method, e.g. the azide method, to give a tetrapeptide of formula IV, whose protecting group is eliminated by the conventional deprotection means to afford the tetrapeptide of formula I readily.</p> |
