Abc amino acids: design, synthesis, and properties of new photoelastic amino acids.
Abc amino acids: design, synthesis, and properties of new photoelastic amino acids.
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Abc 氨基酸：新型光弹性氨基酸的设计、合成和特性。
DOI：
10.1021/jo060763q
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发表时间：
2006
期刊：
影响因子：
--
通讯作者：
Park,SeungBum
中科院分区：
文献类型：
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作者：
Standaert,RobertF;Park,SeungBum
光异构化氨基酸提供了一个直接的途径，实验操作的生物活性多肽，可能允许实时，远程控制的生物系统，并使有用的应用在nanobiotechnology。在此，我们报道了一类新的可光异构化的氨基酸，其旨在引起多肽骨架的显著膨胀和收缩，即，是光弹性的。这些化合物，称为ABC氨基酸，采用可光致异构化的偶氮联苯发色团来控制氨甲基和羧基取代基的相对配置。对9种ABC异构体的分子建模导致鉴定出一种具有特别吸引人的性质的异构体，包括在主链上诱导收缩高达13 π的能力。该异构体命名为mpAbc，分别在内环（偶氮连接）和外环的间位和对位上具有取代基。进行Fmoc保护的mpAbc的有效合成，其中联芳基组分通过Suzuki偶联形成，偶氮键通过胺/亚硝基缩合形成;类似地制备三种其他Abc异构体的保护形式。用固相法合成了一个含有mpAbc的十一肽，它具有偶氮苯的光化学行为，在360 nm处最佳转化为异构体，在80 °C下热顺→反式寿命为100 min。
Photoisomerizable amino acids provide a direct avenue to the experimental manipulation of bioactive polypeptides, potentially allowing real-time, remote control of biological systems and enabling useful applications in nanobiotechnology. Herein, we report a new class of photoisomerizable amino acids intended to cause pronounced expansion and contraction in the polypeptide backbone, i.e., to be photoelastic. These compounds, termed Abc amino acids, employ a photoisomerizable azobiphenyl chromophore to control the relative disposition of aminomethyl and carboxyl substituents. Molecular modeling of nine Abc isomers led to the identification of one with particularly attractive properties, including the ability to induce contractions up to 13 Å in the backbone upontrans→cisphotoisomerization. This isomer, designated mpAbc, has substituents atmetaandparapositions on the inner (azo-linked) and outer rings, respectively. An efficient synthesis of Fmoc-protected mpAbc was executed in which the biaryl components were formed via Suzuki couplings and the azo linkage was formed via amine/nitroso condensation; protected forms of three other Abc isomers were prepared similarly. An undecapeptide incorporating mpAbc was synthesized by conventional solid-phase methods and displayed characteristic azobenzene photochemical behavior with optimal conversion to thecisisomer at 360 nm and a thermalcis→transhalf-life of 100 min at 80 °C.