Twenty-membered rings

Desmopressin, sold under the trade name Ddavp among others, is a medication used to treat diabetes insipidus, bedwetting, hemophilia A, von Willebrand disease, and high blood urea levels. In hemophilia A and von Willebrand disease, it should only be used for mild to moderate cases. It may be given in the nose, by injection into a vein, by mouth, or under the tongue.

Octreotide, sold under the brand name Sandostatin among others, is an octapeptide that mimics natural somatostatin pharmacologically, though it is a more potent inhibitor of growth hormone, glucagon, and insulin than the natural hormone. It was first synthesized in 1979 and binds predominantly to the somatostatin receptors SSTR2 and SSTR5.

Carbetocin, sold under the brand names Pabal among others, is a medication used to prevent excessive bleeding after childbirth, particularly following Cesarean section. It appears to work as well as oxytocin. Due to it being less economical than other options, use is not recommended by NHS Scotland. It is given by injection into a vein or muscle.

Ornipressin is a vasoconstrictor, haemostatic and renal agent.

Vasotocin is an oligopeptide homologous to oxytocin and vasopressin found in all non-mammalian vertebrates (including birds, fishes, and amphibians) and possibly in mammals during the fetal stage of development. Arginine vasotocin (AVT), a hormone produced by neurosecretory cells within the posterior pituitary gland (neurohypophysis) of the brain, is a major endocrine regulator of water balance and osmotic homeostasis and is involved in social and sexual behavior in non-mammalian vertebrates. In mammals, it appears to have biological properties similar to those of oxytocin (stimulating reprodu

chelate of Lu-177 with DOTA-TATE, a peptide derivative bound to a DOTA molecule