In an effort to synthesize potent vasopressin analogs containing photoreactive groups, we prepared, by solid phase synthesis, three analogs with proline or hydroxyproline substitutions in positions 4 and/or 7, lysine in positions 4 or 8, and β‐mercaptopropionic acid in position 1. From these three parent analogs, 1‐des‐amino(4‐proline,8‐lysine]VP, 1‐desamino[4‐hydroxyproline,8‐lysine]VP, and 1‐desamino[4‐lysine,7‐hydroxyproline]AVP, we then prepared the corresponding azido compounds using the ε‐amino group of lysine as the attachment point. These six analogs were then assayed for antidiuretic and pressor activities in rats. One of the resulting analogs, 1‐desamino[4‐lysine(Nε‐4‐azidobenzoyl),7‐hydroxyproline)]AVP has the highest antidiuretic activity of any photoreactive compound reported to date.