<i>N</i>-Hydroxy Amides. X. Synthesis of a Nonapeptide with an Ala-(HO)Gly-Ala Sequence and Its Spectral and Iron(III) Holding Properties
作者:Masayasu Akiyama、Akira Katoh、Masakazu Iijima、Takeshi Takagi、Keiko Natori、Tomoaki Kojima
DOI:10.1246/bcsj.65.1356
日期:1992.5
A nonapeptide with an Ala–(HO)Gly–Ala sequence has been synthesized via condensation of appropriately protected tripeptide units. 1H NMR and CD spectral data indicate that the nonapeptide has a disordered structure in DMSO and water. The peptide forms a 1 : 3 complex of iron(III) with hydroxamate groups at neutral pH when mixed with an aqueous iron(III) solution. The complex shows λmax at 410 nm with
通过适当保护的三肽单元的缩合合成了具有 Ala-(HO)Gly-Ala 序列的九肽。1H NMR 和 CD 光谱数据表明九肽在 DMSO 和水中具有无序结构。当与铁(III)水溶液混合时,该肽在中性pH下形成铁(III)与异羟肟酸酯基团的1:3复合物。该复合物在 410 nm 处显示 λmax,pH 7 下的 e 为 2160。丙氨酸残基影响异羟肟酸酯基团以产生手性复合物,其 CD 光谱显示 355 nm (Δe+0.8) 和 435 nm (Δe-1.8 ),显示出对铁周围的 Δ 构型的偏好。
Iron(III) Complex of a Trihydroxamate Ligand with an Ala-Ala-(HO)Gly-Ala Sequence as a Model for Ferrioxamines. Formation of Well-Defined Peptide Loop Structure
A dodecapeptide trihydroxamate ligand forms a well-defined chiral complex with iron(III) in which this small linear peptide assumes a unique loop conformation, uncommon to protein structures. The complex exhibits siderophore activity for a test microorganism.