[ 4-l-proline ] arginine vasopressin , [ 4-d-proline ] arginine vasopressin , [ 4-hydroxyproline ] arginine vasopressin and [ 4-proline , 7-hydroxyproline ] arginine vasopressin were synthesized and found to have antidiuretic activities of 91 +/- 4 , 1.7 +/- 0.2 , 1.0 +/- 0.1 and 4.4 +/- 1.0 units/mg , respectively .
C0033382
proline
C0020388
hydroxyproline