Synthese von Zwischenprodukten für den Aufbau corticotrop wirksamer Polypeptide. V. Derivate des Pentapeptids H · Val-Lys-Val-Tyr-Pro · OH (β20–24-Corticotropin) und des diastereoisomeren Peptids H · Val-lys-Val-Tyr-Pro · OH
✍ Scribed by R. Schwyzer; B. Riniker; H. Kappeler
- Publisher
- John Wiley and Sons
- Year
- 1963
- Tongue
- German
- Weight
- 566 KB
- Volume
- 46
- Category
- Article
- ISSN
- 0018-019X
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✦ Synopsis
Abstract
Various syntheses of L‐Valyl‐N^ϵ^‐t‐butoxycarbonyl)‐L‐lysyl‐L‐valyl‐L‐tyroxyl‐L‐proline t‐butyl ester (IX) are described. Condensations involving dicyclohexyl carbodiimide and either p‐phenylazo‐benzyloxycarbonyl‐L‐valyl‐(N^ϵ^‐t‐butoxycarbonyl)‐L‐lysine (VII), carbobenzoxy‐L‐valyl‐(N^ϵ^‐t‐butoxycarbonyl)‐L‐lysine (XI), or carbo‐benzoxy‐L‐valyl‐L‐tyroxine (I) produce about 25 per cent racemisation of the C‐terminal amino acids. Carbobenzoxy‐L‐valyl‐(N^ϵ^‐t‐butoxycarbonyl)‐D‐lysyl‐L‐valyl‐L‐tyrosyl‐L‐proline t‐butyl ester (XIIa) was isolated as a cristalline compound with the same m. p. as the «all‐L»‐isomer. Configurations were determined by teh action of trypsin on lysyl peptides and by the action of L‐amino‐acid oxidase on acid hydrolysates.