摘要 |
Nonapeptides and dodecapeptides of the formula… X-Asp-Pro-Tyr-Val-Lys-Glu-Ala-Y (I)… wherein …<CHEM>… or pyro-glutamic acid and Y is Gly, Glu, GlyN(R)2 or GluN(R)2 wherein R is hydrogen or alkyl of 1 to 6 carbon atoms and the pharmaceutically acceptable, nontoxic salts thereof, which augment natural killer cell activity. |