New insights into the palladium-mediated selective hydrolysis of the His18–Thr19 peptide bond in cytochrome c: 1H NMR and density functional theory investigation for model compounds
作者:Xiao-juan Sun、Lin Zhang、Yu Zhang、Gao-sheng Yang、Zi-jian Guo、Long-gen Zhu
DOI:10.1039/b211882c
日期:2003.4.29
atom, an amide nitrogen of methionine and an Nπ atom of imidazole, forming a polycyclic chelate, and is resistant to hydrolysis. The latter, as a model compound for cleavage of the His18–Thr19 bond in cytochrome c with Pd(II) complexes, coordinates to Pd(II) via a sulfur atom, an amide nitrogen and a carbonyl oxygen of histidine to form a polycyclic chelate in which the His–Gly peptide bond is cleaved
这 肽,CH 3 CO-Met-His-GlyH,CH 3 CO-CysMe-His-GlyH,CH 3 CO-CysMe-His-Gly-OEt及其咪唑衍生物,Ñ τ -苄基,Ñ τ甲苯磺酰,Ñ τ苄基Ñ π -phenacyl,已被合成,并用作模型化合物为选择性裂解的机理研究细胞色素c由Pd(II)配合物促进。这肽这些底物的键裂解由顺- [钯(烯)(溶剂)2 ] 2+ (溶剂:D 2 O或CD 3 OD)由1 H NMR光谱。结果表明蛋氨酸含 三肽不同于含S-甲基半胱氨酸三肽以与Pd(II)协调的方式。前者通过硫原子与Pd(II)配位,酰胺 氮 的 蛋氨酸和Ñ π的原子咪唑,形成多环螯合物,并且对 水解。后者,作为裂解His18–Thr19键的模型化合物细胞色素c用Pd(II)络合物,坐标的Pd(II) 经由硫原子,一个酰胺 氮 和一个 羰 氧气 组氨酸 形成多环螯合物,其中His-Gly