Exploring the Scope of an α/β-Aminomutase for the Amination of Cinnamate Epoxides to Arylserines and Arylisoserines
作者:Prakash K. Shee、Nishanka Dilini Ratnayake、Tyler Walter、Olivia Goethe、Edith Ndubuaku Onyeozili、Kevin D. Walker
DOI:10.1021/acscatal.9b01557
日期:2019.8.2
signals confirmed the diastereomeric ratios and relative stereochemistries. Application of a (2S)-threonine aldolase from E. coli further established the absolute stereochemistry of the chiral derivatives of the diastereomeric enzymatically derived products. The 2R:2S ratio for the biocatalyzed anti-isomers was highest (88:12) for 3′-NO2-phenylserine and lowest (66:34) for 4′-F-phenylserine. This showed
cis-Isocytoxazone 2a and trans-isocytoxazone 2h, structural isomers of the antiasthmatic agent cytoxazone (-)-1, and their 5-substituted congeners 23-28 have been prepared. Aldol reaction of para-substituted benzaldehydeswith 7-chloro-1-methyl-5-phenyl-1,4-benzodiazepin-2-one, followed by separation of diastereomeric racemates afforded 3-10. Acid-catalyzed 1,4-benzodiazepine ring opening, and transformation
are central to biotechnological and biomedical chemical processes for their own sake and as substructures of biologically active molecules for diverse biomedical applications. Structurally, these compounds contain a quaternary stereocenter, which is particularly challenging for stereoselective synthesis. The pyridoxal‐5′‐phosphate (PLP)‐dependent L‐serine hydroxymethyltransferase from Streptococcus thermophilus
Scalable and Selective β‐Hydroxy‐α‐Amino Acid Synthesis Catalyzed by Promiscuous
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‐Threonine Transaldolase ObiH
作者:Tyler J. Doyon、Prasanth Kumar、Sierra Thein、Maeve Kim、Abigail Stitgen、Abbigail M. Grieger、Cormac Madigan、Patrick H. Willoughby、Andrew R. Buller
DOI:10.1002/cbic.202100577
日期:2022.1.19
catalyzes the diastereoselective synthesis of β-hydroxy-α-amino acids. We have demonstrated the synthetic utility of this enzyme through preparativescale reactions to selectively generate a structurally diverse array of β-hydroxy-α-amino acids, as well as downstream functionalization to generate important organic building blocks, such as β-chloro-α-amino acids and α-keto acids.
Corrigendum: Scalable and Selective β‐Hydroxy‐α‐Amino Acid Synthesis Catalyzed by Promiscuous
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‐Threonine Transaldolase ObiH
作者:Tyler J. Doyon、Prasanth Kumar、Sierra Thein、Maeve Kim、Abigail Stitgen、Abbigail M. Grieger、Cormac Madigan、Patrick H. Willoughby、Andrew R. Buller
DOI:10.1002/cbic.202200156
日期:2022.4.20
as a carboxylate, and not a carboxylic acid. A corrected Figure 2 is provided. Figure 2 Open in figure viewerPowerPoint Analytical and preparative-scale synthesis of β-hydroxy-α-amino acids by ObiH. Reactions were performed using 20 mM aldehyde, 100 mM l-Thr, 50 mM Tris pH 8.5 and 1–2% ObiH wet whole cells, with 4 % (v/v) MeOH as co-solvent. Preparative scale reactions were incubated at 37 °C for 18 h
化合物22被错误地绘制为衍生自 1-萘醛的异构体,而实际上它是衍生自 2-萘醛。化合物15也应绘制为羧酸盐,而不是羧酸。提供了修正后的图 2。 图 2 在图形查看器中打开微软幻灯片软件 通过 ObiH 进行 β-羟基-α-氨基酸的分析和制备规模合成。使用 20 mM 醛、100 mM l- Thr、50 mM Tris pH 8.5 和 1-2% ObiH 湿全细胞进行反应,4% (v/v) MeOH 作为共溶剂。制备规模反应在 37°C 下孵育 18 小时,然后用 1 体积当量的 MeCN 淬灭,然后冻融和离心以去除细胞碎片。使用Biotage纯化系统通过反相色谱进行纯化。产量报告为冻干后分离的产物质量。1 H NMR水合分析用于校正过量水的产率值。在用 Marfey 试剂衍生后,通过 UPLC-PDA-MS 测定的分析规模产品产率。 第 4 页第 2 段也对相应文本进行了更正: “相反,为了进一步探索