The structure of calcitonin isolated from salmon1 (SCT 1) has been recently established2 and confirmed by synthesis8. It possesses an exceptionally high level of activity, exhibiting about 20–50 times the hypocalcaemic potency of any other calcitonin isolated from mammalian species.

AbstractDas Nonapeptidamid (IV) wird nach der Azidmethode mit dem Heptapeptidhydrazid (III) gekuppelt und die Benzyloxycarbonylgruppe hydrogenolytisch gespalten.

AbstractA total synthesis of salmon calcitonin is described. The C‐terminal nonapeptide amide 24–32 was coupled with the heptapeptide 17–23. The resulting hexadecapeptide amide 17–32 was reacted with the heptapeptide 10–16 to give the tricosapeptide 10–32. This was condensed with the N‐terminal nonapeptide 1–9, yielding the protected dotriacontapeptide amide 1–32. After removal of the protective groups and purification by gel‐filtration the free peptide obtained exhibited the physical, chemical and biological properties of the natural hormone. Its hypocalcaemic activity (ca. 3500 MRC U/mg) is 20–30 times higher than that of porcine or human calcitonin.

AbstractThe syntheses of the alkaloids of the ergotoxine‐group i.e. ergocristine, α‐ and β‐ergokryptine, and ergocornine, are described. Using starting material with known stereochemistry these syntheses allowed to determine the absolute configurations also at C‐2′ and C‐12′ in the peptide part, which could not be derived from analytical data. All ergot alkaloids of the peptide type possess the same stereochemical structure.

A total synthesis of hog thyrocalcitonin is described. A protected C-terminal tridecapeptide amid (20–32) was coupled with a protected central decapeptide (10–19), and the resulting protected tricosapeptide amide (10–32) was reacted with the N-terminal protected nonapeptide (1–9). After elimination of the protective groups, a free dotriacontapeptide amide was obtained whose physical, chemical and biological behaviour was indistinguishable from that of the natural hormone.

AbstractHog thyrocalcitonin has been isolated in the form of an homogeneous peptide. After digestion with trypsin three fragments have been separated by paper electrophoresis. the amino acid composition of intact thyrocalcitonin and of the three tryptic fragments is given in a table.

Le nouveau pentacosapeptided-séryl-l-tyro-syl-l-séryl-l-norleucyl-l-glutamyl-l-histidyl-l-phényl-alanyl-l-arginyl-l-tryptophanyl-glycyl-l-lysyl-l-prolyl-l-valyl-glycyl-l-lysyl-l-lysyl-l-arginyl-l-arginyl-l-prolyl-l-valyl-l-lysyl-l-valyl-l-tyrosyl-l-prolyl-l-valinamide a été synthétisé par des méthodes évitant la racémisation. Ce pentacosapeptide possède une activité corticotrope très élevée (env. 625 U.I./mg base libre; cf. les deux communications suivantes), ne contient pas le reste méthionine facilement oxydable de l'ACTH naturelle, et est résistant à l'action des amino-et carboxy-peptidases.

Helvetica Chimica ActaVolume 49, Issue 1 p. 83-96 Article Synthèse du glutathion et de l'oxytocine à l'aide d'un nouveau groupe protecteur de la fonction thiol† St. Guttmann, St. Guttmann Laboratoires de chimie pharmaceutique Sandoz S.A., BaleSearch for more papers by this author St. Guttmann, St. Guttmann Laboratoires de chimie pharmaceutique Sandoz S.A., BaleSearch for more papers by this author First published: 1966 https://doi.org/10.1002/hlca.660490115Citations: 49 † Une communication préliminaire de ce travail a été présenté au 6e Symposium européen sur les peptides le 15 sept., 1963 à Athènes. AboutPDF ToolsRequest permissionExport citationAdd to favoritesTrack citation ShareShare Give accessShare full text accessShare full-text accessPlease review our Terms and Conditions of Use and check box below to share full-text version of article.I have read and accept the Wiley Online Library Terms and Conditions of UseShareable LinkUse the link below to share a full-text version of this article with your friends and colleagues. Learn more.Copy URL Citing Literature Volume49, Issue11966Pages 83-96 RelatedInformation

Publisher Summary This chapter discusses the use of the S-ethyl carbamoyl group for protection of the thiol function of cysteine. A large number of biologically important peptides such as ribonuclease, insulin, oxytocin, and vasopressin contain one or several cystine residues in their sequences. During the synthesis of such peptides, the thiol group of cysteine is blocked because of its high reactivity and oxidizability. If several cysteine residues are present, it can be necessary to deblock them not simultaneously but gradually one after the other. For this purpose, selectively removable thiol blocking groups are needed. The ethylcarbamoyl group, which is very easily introduced by treating dry cysteine hydrochloride with ethyl isocyanate, can be a useful protecting group for the thiol function of cysteine. The synthesis of glutathione is an example of simultaneous hydrolytic cleavage or S-carbamoyl and ester groups. The N-Z-group can be cleaved before or after the elimination of the S-carbamoyl and ester groups.

AbstractAla1‐Ala6‐Arg8‐vasopressin, Ala1‐Ala6‐Lys8‐vasopressin, (Deamino‐Ala)1‐Ala6‐Arg8‐vasopressin and (Deamino‐Ala)1‐Ala6‐Lys8‐vasopressin were prepared by condensation of a tripeptide azide or, respectively, a propionyl‐dipeptide azide with a hexapeptide amide, both fragments having been synthesized by methods excluding racemization. These peptides represent analogues of arginine‐vasopressin, lysinevasopressin and of their deamino derivatives, in which the ring is open and the sulphur atoms are replaced by hydrogen atoms. The new peptides were found to be devoid of any biological activity and did not inhibit the corresponding natural hormones. The significance of this observation is discussed.