Amino Acids and Peptides. VI. Novel Peptide Bond Formation catalyzed by Metal Ions. IV. Formation of optically Active Amino Acid Amides and Peptide Amides
作者:MITSUYOSHI WAGATSUMA、SHIRO TERASHIMA、SHUN-ICHI YAMADA
DOI:10.1248/cpb.21.422
日期:——
The Cu (II)-catalyzed peptide bond formation previously reported by us, was applied to the synthesis of optically active amino acid amides and peptide amides. Treatment of an optically active amino acid ester with a primary amine in the presence of anhydrous CuCl2 afforded the desired amino acid secondary amide, without racemization, in 60-70% yield. However, the same reaction with a secondary amine with larger steric hindrance than primary amine gave an optically active tertiary amide in a very low yield as expected from the proposed mechanism. Almost all the amino acid amides could be isolated as hydrochlorides or as free bases. Some peptide amides, i. e. Z-Gly-Gly-NH-Bzl, and Z-Ala-Gly-NH-Bzl, were also prepared.
我们之前报道的Cu(II)催化肽键形成反应,被应用于光学活性氨基酸酰胺和肽酰胺的合成。在无水CuCl2的存在下,将光学活性氨基酸酯与一级胺反应,可以获得所需的氨基酸次级酰胺,且未发生消旋化,产率为60-70%。然而,与具有比一级胺更大空间位阻的二级胺进行相同反应,根据提出的机理预期,得到的光学活性三级酰胺产率非常低。几乎所有的氨基酸酰胺都可以分离为盐酸盐形式或游离碱形式。一些肽酰胺,例如Z-Gly-Gly-NH-Bzl和Z-Ala-Gly-NH-Bzl,也被制备出来。