Practical Pd(II)-Catalyzed C–H Alkylation with Epoxides: One-Step Syntheses of 3,4-Dihydroisocoumarins
摘要:
Pd(II)-catalyzed ortho-alkylation of benzoic acids with both terminal and internal epoxides affords 3,4-dihydroisocoumarins in one step. The presence of potassium countercations is crucial for this reaction. Monoprotected amino acid ligands significantly promote this reaction, enabling the development of a practical C-H alkylation reaction using 0.5 mol % Pd catalyst. The inversion of stereochemistry in the C-H alkylation step is consistent with a redox-neutral S(N)2 nucleophilic ring-opening process as opposed to a Pd(II)/Pd(IV) pathway.
Ligand‐Enabled Catalytic CH Arylation of Aliphatic Amines by a Four‐Membered‐Ring Cyclopalladation Pathway
作者:Chuan He、Matthew J. Gaunt
DOI:10.1002/anie.201508912
日期:2015.12.21
palladium‐catalyzed CHarylation of aliphaticamines with arylboronic esters is described, proceeding through a four‐membered‐ringcyclopalladationpathway. Crucial to the successful outcome of this reaction is the action of an amino‐acid‐derived ligand. A range of hindered secondary amines and arylboronic esters are compatible with this process and the products of the arylation can be advanced to
Direct monitoring of biocatalytic deacetylation of amino acid substrates by <sup>1</sup>H NMR reveals fine details of substrate specificity
作者:Silvia De Cesare、Catherine A. McKenna、Nicholas Mulholland、Lorna Murray、Juraj Bella、Dominic J. Campopiano
DOI:10.1039/d1ob00122a
日期:——
Amino acids are key synthetic building blocks that can be prepared in an enantiopure form by biocatalytic methods. We show that the L-selective ornithine deacetylase ArgE catalyses hydrolysis of a wide-range of N-acyl-amino acid substrates. This activity was revealed by 1H NMR spectroscopy that monitored the appearance of the well resolved signal of the acetate product. Furthermore, the assay was used
氨基酸是关键的合成构件,可以通过生物催化方法制备对映体纯形式。我们发现L-选择性鸟氨酸脱乙酰酶 ArgE 催化多种N-酰基氨基酸底物的水解。该活性通过1 H NMR 光谱来揭示,该光谱监测了乙酸盐产物的清晰信号的出现。此外,该测定还使用可以采用不同旋转异构体构象的底物来探测生物催化剂的微妙结构选择性。
[EN] HEPATITIS C VIRUS NS3/4A PROTEASE INHIBITORS<br/>[FR] INHIBITEURS DE PROTÉASE NS3/4A DU VIRUS DE L'HÉPATITE C
申请人:UNIV MASSACHUSETTS
公开号:WO2018236928A1
公开(公告)日:2018-12-27
The invention provides novel classes of HCV therapeutics that are orally available, safe and effective HCV NS3/4A protease inhibitors and are less susceptible to drug resistance than existing therapeutics. The invention also relates to pharmaceutical composition of these compounds and methods of preparation and use thereof.
Provided herein (among other things) are protease inhibitor compounds having enhanced features, along with methods for administering such compounds. For example, the subject compounds can be administered without concomitant administration of a CYP3A4 inhibitor, have increased therapeutic index and/or increased potency, and are low-resistance inducing in nature.
Remote Amino Acid Recognition Enables Effective Hydrogen Peroxide Activation at a Manganese Oxidation Catalyst
作者:Laia Vicens、Giorgio Olivo、Miquel Costas
DOI:10.1002/anie.202114932
日期:2022.2.7
Aminoacid supramolecular recognition in the 2nd coordination sphere of a bioinspired manganesecatalyst allows efficient enzyme-like activation of H2O2 by locating the carboxylic acid moiety in proper position to access the 1st coordination sphere of the metal.
仿生锰催化剂的第二配位层中的氨基酸超分子识别通过将羧酸部分定位在适当的位置以进入金属的第一配位层,从而实现 H 2 O 2的有效酶样活化。