On November 7, 1984, Felix, Arthur Martin; Meienhofer, Johannes Arnold; Trzeciak, Arnold; Gillessen, Dieter; Studer, Rolf published a patent.Quality Control of (S)-5-tert-Butyl 1-methyl 2-aminopentanedioate The title of the patent was Intermediates for thymosin α1 and desacetylthymosin α1. And the patent contained the following:
R-Ser(CMe3)-Asp(OCMe3)-Ala-Ala-Val-Asp(OCMe3)-Thr(CMe3)-Ser(CMe3)-Ser(CMe3)-Glu(OCMe3)-OR1 [I; R = Ac, Me3CO2C (Boc); R1 = H, Ph] were prepared as intermediates for the synthesis of thymosin α1 (II, R2 = Ac) and desacetylthymosin α1 (II, R2 = H). Thus, Ac-Ser(CMe3)-Asp(OCMe3)-Ala-ONSu (III, NSu = succinimido) was coupled with H-Ala-Val-Asp(OCMe3)-Thr(CMe3)-Ser(CMe3)-Ser(CMe3)-Glu(OCMe3)-OPh (IV) to give I (R = Ac, R1 = Ph), which was saponified in the presence of H2O2 to give I (R = Ac, R1 = H) (V). Z-Ile-Thr(CMe3)-Thr(CMe3)-Lys(Boc)-Asp(OCMe3)-Leu-Lys(Boc)-Glu(OCMe3)-Lys(Boc)-Lys(Boc)-Glu(OCMe3)-Val-Val-Glu(OCMe3)-Glu(OCMe3)-Ala-Glu(OCMe3)-Asn-OCMe3 (VI, Z = PhCH2O2C) was Z-deblocked by hydrogenolysis and then coupled with V by DCC/1-hydroxybenzotriazole to give protected thymosin α1, which was deblocked by CF3CO2H to give II (R2 = H). VI was prepared by a series of fragment condensations from H-Glu(OCMe3)-Ala-Glu(OCMe3)-Asn-OCMe3 (VII), Z-Glu(OCMe3)-Val-Val-Glu(OCMe3)-OH (VIII), Z-Glu(OCMe3)-Lys(Boc)-Lys(Boc)-OH (IX), Z-Asp(OCMe3)-Leu-Lys(Boc)-OH (X), and Z-Ile-Thr(CMe3)-Thr(CMe3)-Lys(Boc)-OH (XI). III, IV, and VII-XI were prepared by conventional solution methods. The experimental process involved the reaction of (S)-5-tert-Butyl 1-methyl 2-aminopentanedioate(cas: 53838-27-0).Quality Control of (S)-5-tert-Butyl 1-methyl 2-aminopentanedioate
The Article related to thymosin preparation peptide intermediate, desacetylthymosin preparation peptide intermediate, Amino Acids, Peptides, and Proteins: Poly(Amino Acids) and Peptides and other aspects.Quality Control of (S)-5-tert-Butyl 1-methyl 2-aminopentanedioate
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