C12 Helices in Long Hybrid (伪纬)n Peptides Composed Entirely of Unconstrained Residues with Proteinogenic Side Chains

详细信息    查看全文

• 作者：Rajesh Sonti ; Bhimareddy Dinesh ; Krishnayan Basuroy ; Srinivasarao Raghothama ; Narayanaswamy Shamala ; Padmanabhan Balaram
• 刊名：Organic Letters
• 出版年：2014
• 出版时间：March 21, 2014
• 年：2014
• 卷：16
• 期：6
• 页码：1656-1659
• 全文大小：363K
• 年卷期：v.16,no.6(March 21, 2014)
• ISSN：1523-7052

文摘

Unconstrained 纬⁴ amino acid residues derived by homologation of proteinogenic amino acids facilitate helical folding in hybrid (伪纬)_n sequences. The C₁₂ helical conformation for the decapeptide, Boc-[Leu-纬⁴(R)Val]₅-OMe, is established in crystals by X-ray diffraction. A regular C₁₂ helix is demonstrated by NMR studies of the 18 residue peptide, Boc-[Leu-纬⁴(R)Val]₉-OMe, and a designed 16 residue (伪纬)_n peptide, incorporating variable side chains. Unconstrained (伪纬)_n peptides show an unexpectedly high propensity for helical folding in long polypeptide sequences.