Ac-ΔTyr(Ac)-(R)-Ala-OH

Ac-ΔTyr(Ac)-(R)-Ala-Gly-(S)-Phe-OMe

(S)-2-(2-{(R)-2-[(R)-3-(4-Acetoxy-phenyl)-2-acetylamino-propionylamino]-propionylamino}-acetylamino)-3-phenyl-propionic acid methyl ester