- 著者
-
田中 正一
- 出版者
- The Society of Synthetic Organic Chemistry, Japan
- 雑誌
- 有機合成化学協会誌 (ISSN:00379980)
- 巻号頁・発行日
- vol.60, no.2, pp.125-136, 2002-02-01 (Released:2009-11-13)
- 参考文献数
- 55
- 被引用文献数
-
15
19
Replacement of α-hydrogen atom of α-amino acids with alkyl substituents affords α, α-disubstituted α-amino acids, which are non-proteinogenic amino acids. This kind of modification changes the conformational freedom of peptides containing such residues. 2-Aminoisobutyric acid (dimethylglycine, Aib) is a natural product, isolated as a component of peptaibol antibiotics, and is widely used among peptide chemists for the construction of helical secondary structure. Contrary to 310-helical structure of Aib homopeptides, the conformation of homopeptides prepared from diethylglycine or dipropylglycine is a fully planar C5-conformation. Besides achiral α, α-disubstituted α-amino acids, the conformation of homopeptides prepared from chiral α-methylated or α-ethylated α, α-disubstituted α-amino acids was recently reported. The conformation of homopeptides prepared from chiral α-methylated α, α-disubstituted amino acids is the 310-helical structure and the screw sense of helicity (P) or (M) depends on the chirality of quaternary carbon center of amino acids, while that of α-ethylated α, α-disubstituted amino acids is the fully planar C5-conformation. The application of α, α-disubstituted α-amino acids for the design of biologically active peptides and catalytic peptides is also described.