Solid phase synthesis and some pharmacological properties of 8-D-homolysine-vasopressin and 1-deamino-8-D-homolysine-vasopressin.

8-DL-Homolysine-vasopressin and its 1-deamino derivative were synthesized by the solid phase method. The desired D-homolysine analogues were obtained by digestion of the mixtures with trypsin and isolation of the peptide components by ion-exchange chromatography. In agreement with earlier observations on vasopressins containing alpha, omega-diamino acids of D configuration the new analogues show very low pressor activities. However, the antidiuretic effects are surprisingly high, thus reversing the known activity trend and making the D-homolysine analogues highly selective antidiuretic agents.