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1. Catalytic Chemo‐ and Regioselective Radical Carbocyanation of 2‐Azadienes for the Synthesis of α‐Amino Nitriles

   https://doi.org/10.1002/anie.202300605  

   Duan, Shengzu; Du, Ya; Wang, Lingling; Tian, Xun; Zi, Yujin; Zhang, Hongbin; Walsh, Patrick J.; Yang, Xiaodong (March 2023, Angewandte Chemie International Edition)

   Abstract α‐Amino nitriles are versatile structural motifs in a variety of biologically active compounds and pharmaceuticals and they serve as valuable building blocks in synthesis. The preparation of α‐ and β‐functionalized α‐amino nitriles from readily available scaffolds, however, remains challenging. Herein is reported a novel dual catalytic photoredox/copper‐catalyzed chemo‐ and regioselective radical carbocyanation of 2‐azadienes to access functionalized α‐amino nitriles by using redox‐active esters (RAEs) and trimethylsilyl cyanide. This cascade process employs a broad scope of RAEs and provides the corresponding α‐amino nitrile building blocks in 50–95 % yields (51 examples, regioselectivity >95 : 5). The products were transformed into prized α‐amino nitriles and α‐amino acids. Mechanistic studies suggest a radical cascade coupling process. 

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2. Amino mapping: possibility to visualize amino-N compounds in the rhizosphere of Zea Mays L.

   https://doi.org/10.1007/s00374-023-01754-0  

   Khosrozadeh, Sajedeh; Guber, Andrey; Nourbakhsh, Farshid; Khalili, Banafshe; Blagodatskaya, Evgenia (July 2023, Biology and Fertility of Soils)

   Abstract Understanding N uptake by plants, the N cycle, and their relationship to soil heterogeneity has generated a great deal of interest in the distribution of amino-N compounds in soil. Visualization of the spatial distribution of amino-N in soil can provide insights into the role of labile N in plant-microbial mechanisms of N acquisition and plant N uptake, but until now, it has remained technically challenging. Here, we describe a novel technique to visualize the amino-N distribution at the root-soil interface. The technique is based on time-lapse amino mapping (TLAM) using membranes saturated with the fluorogenic OPAME reagent ( O -phthalaldehyde and β-mercaptoethanol). OPAME in the membrane reacts with organic compounds containing a NH 2 functional group at the membrane-soil interface, generating a fluorescent product visible under UV light and detectable by a digital camera. The TLAM amino-mapping technique was applied to visualize and quantify the concentration of amino-N compounds in the rhizosphere of maize ( Zea Mays L.). A ten times greater amino-N concentration was detected in the rhizosphere compared to non-rhizosphere soil. The high content of amino-N was mainly associated with the root tips and was 3 times larger than the average amino-N content at seminal roots. The amino-N rhizosphere was 2 times broader around the root tips than around other parts of the roots. We concluded that TLAM is a promising approach for monitoring the fate of labile N in soils. However, the technique needs to be standardized for different soil types, plant species, and climate conditions to allow wider application. 

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3. Molecular recognition of methylated amino acids and peptides by Pillar[6]MaxQ

   https://doi.org/10.1039/D2OB01487D  

   King, David; Wilson, Chelsea R.; Herron, Lukas; Deng, Chun-Lin; Mehdi, Shams; Tiwary, Pratyush; Hof, Fraser; Isaacs, Lyle (September 2022, Organic & Biomolecular Chemistry)

   We report the molecular recognition properties of Pillar[ n ]MaxQ (P[ n ]MQ) toward a series of (methylated) amino acids, amino acid amides, and post-translationally modified peptides by a combination of 1 H NMR, isothermal titration calorimetry, indicator displacement assays, and molecular dynamics simulations. We find that P6MQ is a potent receptor for N -methylated amino acid side chains. P6MQ recognized the H3K4Me 3 peptide with K d = 16 nM in phosphate buffered saline. 

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4. Thionation of the 2‐λ ⁵ ‐Phosphaquinolin‐2‐one Scaffold with Lawesson's Reagent

   https://doi.org/10.1002/ijch.202000085  

   Bard, Jeremy P.; McNeill, J. Nolan; Warren, Gabrielle I.; Zakharov, Lev N.; Johnson, Darren W.; Haley, Michael M. (December 2020, Israel Journal of Chemistry)

   Abstract Lawesson's reagent is one of the most common thionating reagents that has found use for several decades on a variety of carbonyl systems. Herein, we report the transformation of the 2‐λ⁵‐phosphaquinolin‐2‐one structure to its respective 2‐λ⁵‐phosphaquinolin‐2‐thione derivative. Solution‐state characterization of both P−OPh and P−Ph thio analogues, as well as solid‐state structures for the latter system, are reported. 

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5. N -(5-Cyanononan-5-yl)benzamide

   https://doi.org/10.1107/S2414314623006399  

   Song, Xueqing; Li, William (July 2023, IUCrData)

   N -(5-Cyanononan-5-yl)benzamide, C 17 H 24 N 2 O, synthesized from the reaction between benzoyl chloride and 2-amino-2-butylhexanenitrile, is an important intermediate in amino acid synthesis. Intermolecular N—H...O and C—H...O hydrogen bonds with N...O and C...O distances of 3.083 (2) and 3.304 (2) Å, respectively, link adjacent molecules into chains along the a axis. The dihedral angle between the mean plane of the phenyl group and the plane of the amide group is 19.504 (4)°. 

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