SYNTHESIS OF [8‐α‐HYDROXYISOCAPROIC ACID] OXYTOCIN

The synthesis and biological activities of [8-α-hydroxyisocaproic acid] oxytocin are reported. The in vivo uterine responses to [8-α-hydroxyisocaproic acid] oxytocin are prolonged and those to deamino-[8-α-hydroxyisocaproic acid] oxytocin (as well as those we have previously reported for deamino-oxytocin) are very prolonged as compared with those to oxytocin. Time courses of the in vivo uterine responses to deamino-[8-α-hydroxyisocaproic acid] oxytocin and deamino-oxytocin (as followed by plotting the intervals between the individual contractions of a response vs. time after peptide injection) differ from those to [8-α-hydroxyisocaproic acid] oxytocin and oxytocin.