ICB, Padova Unit, CNR, Department of Chemistry, University of Padova, via Marzolo 1, 35131 Padua, Italy.
Amino Acids. 2011 Aug;41(3):629-41. doi: 10.1007/s00726-011-0839-9. Epub 2011 Feb 4.
The synthesis of the N-protected (blocked) homo-peptide esters from the chiral C(α)-ethyl, C(α)-n-pentylglycine was performed in solution to the hexapeptide level. The conformational propensity exhibited by these oligomers in chloroform solution and in the crystal state was assessed by use of FTIR absorption, NMR, and X-ray diffraction. The results indicated that fully extended helical structures (2.0(5)-helices) are overwhelmingly adopted irrespective of the peptide main-chain length. This oligomeric series is of great interest as it is characterized by the longest C ( i )(α) ,…, C ( i+1 )(α) (per residue) separation achievable in the class of chiral, rigid, helical peptide spacers based on α-amino acids.
从手性 C(α)-乙基、C(α)-正戊基甘氨酸合成 N-保护（封闭）同肽酯，在溶液中进行到六肽水平。通过傅里叶变换红外吸收、核磁共振和 X 射线衍射评估这些低聚物在氯仿溶液和晶体状态下的构象倾向。结果表明，无论肽主链长度如何，完全伸展的螺旋结构（2.0(5)-螺旋）都被广泛采用。该低聚物系列非常有趣，因为它的特点是在基于α-氨基酸的手性、刚性、螺旋肽间隔物类中，可以实现最长的 C(i)(α)、…、C(i+1)(α)(每残基)分离。
