On April 7, 1977, Wuensch, Erich; Wendlberger, Gerhard; Jaeger, Ernst published a patent.COA of Formula: C10H19NO4 The title of the patent was L-Leucine-13-motiline. And the patent contained the following:
H-Phe-Val-Pro-Ile-Phe-Thr-Tyr-Gly-Glu-Leu-Gln-Arg-Leu-Glu-Glu-Lys-Glu-Arg-Asn-Lys-Gly-Gln-OH (I), 13-L-leucine-motiline, was prepared by peptide fragment condensations. Thus, Z-Asn-Lys(BOC)-OH (Z = PhCH2O2C, BOC = Me3CO2C) and H-Gly-Gln-OCMe3 were prepared and coupled together by dicyclohexylcarbodiimide (DCC) in the presence of N-hydroxysuccinimide (HOSu) to give the protected tetrapeptide. The latter was Z-deblocked by hydrogenation and then coupled to Z-Arg(Z2)-OC6H4NO2-4 to give the protected pentapeptide which was hydrogenated and treated with HBr to give H-Arg-Asn-Lys(BOC)-Gly-Gln-OCMe3.2HBr (II), the protected 18-22 sequence of I. Z-Glu(OCMe3)-Glu(OCMe3)-Lys(BOC)-Glu(OCMe3)-OH (III), the 14-17 sequence, Z-Arg(Z2)-Leu-OH (IV), the 12-13 sequence, Z-Glu(OCMe3)-Leu-Gln-OH (V), the 9-11 sequence, H-Thr(CMe3)-Tyr(CMe3)-Gly-OH (VI), the 6-8 sequence, and BOC-Phe-Val-Pro-Ile-Pro-OH (VII), the 1-5 sequence, were also prepared II was coupled to III by DCC-HOSu to give the protected 14-22 sequence which was Z-deblocked and coupled to IV by DCC-HOSu to give the protected 12-22 sequence. The latter was Z-deblocked and coupled to V by DCC-HOSu to give the protected 9-11 sequence which was Z-deblocked and coupled to the protected 1-8 sequence to give the protected 1-22 sequence. The latter was deblocked with CF3CO2H to give I. The protected 1-8 sequence was prepared by coupling VI to VII by the HOSu active ester. The experimental process involved the reaction of (S)-5-tert-Butyl 1-methyl 2-aminopentanedioate(cas: 53838-27-0).COA of Formula: C10H19NO4
The Article related to leucine motiline, peptide motiline, Synthesis of Amino Acids, Peptides, and Proteins: Peptides and other aspects.COA of Formula: C10H19NO4
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