An artificial metalloenzyme with the kinetics of native enzymes
作者:P. Dydio、H. M. Key、A. Nazarenko、J. Y.-E. Rha、V. Seyedkazemi、D. S. Clark、J. F. Hartwig
DOI:10.1126/science.aah4427
日期:2016.10.7
containing an iridium porphyrin that exhibits kinetic parameters similar to those of natural enzymes. In particular, variants of the P450 enzyme CYP119 containing iridium in place of iron catalyzeinsertions of carbenes into C–H bonds with up to 98% enantiomeric excess, 35,000 turnovers, and 2550 hours−1 turnover frequency. This activity leads to intramolecular carbene insertions into unactivated C–H
Abiological catalysis by artificial haem proteins containing noble metals in place of iron
作者:Hanna M. Key、Paweł Dydio、Douglas S. Clark、John F. Hartwig
DOI:10.1038/nature17968
日期:2016.6.23
centres in native metalloenzymes. To overcome this limitation, artificial metalloproteins have been created by incorporating complete, noble-metal complexes within proteins lacking native metal sites. The interactions of the substrate with the protein in these systems are, however, distinct from those with the native protein because the metal complex occupies the substrate bindingsite. At the intersection
含有金属离子的酶——即金属酶——具有过渡金属中心的反应性和分子进化的潜力,可以调节系统的反应性和底物选择性。通过利用底物混杂和蛋白质工程,天然金属酶催化的反应范围最近已扩大到包括非生物转化。然而,这种策略受到天然金属酶中金属中心固有反应性的限制。为了克服这一限制,人工金属蛋白已通过在缺乏天然金属位点的蛋白质中掺入完整的贵金属复合物来制造。然而,在这些系统中,底物与蛋白质的相互作用是 与天然蛋白质不同,因为金属络合物占据了底物结合位点。在这些方法的交叉点是第三种策略,其中金属酶的天然金属被一种生物金属取代,其反应性不同于天然蛋白质中金属的反应性。这种策略可以在可以进行定向进化的酶的天然底物结合位点内创建用于生物催化的人工酶。在这里,我们报告了用生物贵金属正式取代铁卟啉 IX (Fe-PIX) 蛋白中的铁,以产生催化天然 Fe 酶或其他金属酶不催化的反应的酶。尤其,我们制备了含有 Ir(Me)
Asymmetric Intramolecular C−H Insertions of Aryldiazoacetates
作者:Huw M. L. Davies、Mônica V. A. Grazini、Emmanuel Aouad
DOI:10.1021/ol0157858
日期:2001.5.1
[GRAPHICS]The enantioselectivity of Rh-2(SDOSP)(4) catalyzed C-H insertion of aryldiazoacetates is very dependent on the site of the C-H insertion. The highest enantioselectivity is obtained for insertion into methine C-H bonds.
Enantio- and Diastereoselective Synthesis of <i>cis</i>-2-Aryl-3-methoxycarbonyl-2,3-dihydrobenzofurans via the Rh(II)-Catalyzed C−H Insertion Process
[GRAPHICS]The enantioselective intramolecular C-H insertion reaction of aryldiazoacetates has been explored with use of dirhodium(II) carboxylate catalysts, which incorporate N-phthaloyl- or N-benzene-fused-phthaloyl-(S)-amino acids as chiral bridging ligands. Dirhodium tetrakis[N-phthaloyl-(S)tert-leucinate], Rh-2(S-PTTL)(4), has proven to be the catalyst of choice for this process, providing exclusively cis-2-aryl-3-methoxycarbonyl-2,3-dihydobenzofurans in up to 94% ee.