A New Essential Oil from the Leaves of <i>Gynoxys rugulosa</i> Muschl. (Asteraceae) Growing in Southern Ecuador: Chemical and Enantioselective Analyses by Yessenia E. Maldonado, Omar Malagón, Nixon Cumbicus, Gianluca Gilardoni

“…The enantiomers of α-pinene, β-pinene, sabinene, α-phellandrene, β-phellandrene, linalool, α-copaene, terpinen-4-ol, α-terpineol, and germacrene D were detected, and the respective enantiomeric excess was calculated.…”
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Improved automated one-pot two-step radiosynthesis of (S)-[18F]FETrp, a radiotracer for PET imaging of indoleamine 2,3-dioxygenase 1 (IDO1) by Aurélie Maisonial-Besset, David Kryza, Klaus Kopka, Sophie Levesque, Emmanuel Moreau, Barbara Wenzel, Jean-Michel Chezal

“…Based on these results, the (S)-[18F]FETrp radiosynthesis was fully automated on a SynChrom R&D EVOI module to produce the radiotracer in 55.2 ± 7.5% radiochemical yield, 99.9% radiochemical purity, 99.1 ± 0.5% enantiomeric excess, and molar activity of 53.2 ± 9.3 GBq/µmol (n = 3). …”
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Highly selective kinetic resolution of D/L-syn-p-sulfone phenylserine catalyzed by d-threonine aldolase in two-phase ionic solvent by Fengfan Liu, Zhihao Shi, Jinmei Zhu, Xiaobin Liang, Mingming Liang, Yuanyuan Xie, Weike Su, Jiequn Wu

“…The D/L-syn-MPS racemate was resolved using a two-phase ionic solvent [BMIM][NTf2] to afford L-syn-MPS (ee (enantiomeric excess) > 99%) and a white solid in 41.7% yield. …”
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Synthesis of a Chiral 3,6T22-Zn-MOF with a T-Shaped Bifunctional Pyrazole-Isophthalate Ligand Following the Principles of the Supramolecular Building Layer Approach by Dennis Woschko, Simon Millan, Muhammed-Ali Ceyran, Robert Oestreich, Christoph Janiak

“…The metal–organic framework (MOF) [Zn(Isa-az-tmpz)]·~1–1.5 DMF with the novel T-shaped bifunctional linker 5-(2-(1,3,5-trimethyl-1H-pyrazol-4-yl)azo)isophthalate (Isa-az-tmpz) was obtained as a conglomerate of crystals with varying degrees of enantiomeric excess in the chiral tetragonal space groups P4₃2₁2 or P4₁2₁2. …”
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Production of an Anise- and Woodruff-like Aroma by Monokaryotic Strains of <i>Pleurotus sapidus</i> Grown on <i>Citrus</i> Side Streams by Friederike Bürger, Maximilian Koch, Marco A. Fraatz, Alejandra B. Omarini, Ralf G. Berger, Holger Zorn

“…Chiral analysis via HPLC revealed an enantiomeric excess of 97% for the isolated product produced by <i>P. sapidus.…”
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The Leaf Essential Oil of <i>Gynoxys buxifolia</i> (Kunth) Cass. (Asteraceae): A Good Source of Furanoeremophilane and Bakkenolide A by Carolina Cumbicus, Omar Malagón, Nixon Cumbicus, Gianluca Gilardoni

“…In this analysis, (1<i>S</i>,5<i>S</i>)-(−)-α-pinene, (1<i>S</i>,5<i>S</i>)-(−)-β-pinene, (<i>S</i>)-(+)-α-phellandrene, (<i>S</i>)-(+)-β-phellandrene, and (<i>S</i>)-(−)-terpinen-4-ol were detected as enantiomerically pure, whereas (<i>S</i>)-(−)-sabinene showed an enantiomeric excess of 69.2%. The essential oil described in the present study is a good source of two uncommon volatile compounds: furanoeremophilane and bakkenolide A. …”
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Nickel-catalyzed coupling reactions and synthetic studies toward ent-dioxepandehydrothyrsiferol via an epoxide-opening cascade by Ng, Sze-Sze

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Fundamentals and applications of a nanoconfined electrochemical reactor for rapid biosynthesis by Wan, L

“…Enantioselective oxidation and reduction reactions were conducted sequentially on a racemic mixture of enantiopure secondary alcohols, leading to >90\% enantiomeric excess in both (R) and (S).</p> …”

Rational design of mimetic peptides based on promiscuous aldo-ketoreductase enzyme as asymmetric catalysts in aldol and Michael reactions by Bayat, Saadi

“…Mechanism study demonstrated that enamine intermediate and hydrogen-bonding interaction are very important for obtaining high enantiomeric excess. The reusability of peptide 4 as the best catalyst was also conducted for 10 times. …”
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Novel Bispidine-Monoterpene Conjugates—Synthesis and Application as Ligands for the Catalytic Ethylation of Chalcones by Evgeniy V. Suslov, Konstantin Y. Ponomarev, Oxana S. Patrusheva, Sergey O. Kuranov, Alina A. Okhina, Artem D. Rogachev, Aldar A. Munkuev, Roman V. Ottenbacher, Alexander I. Dalinger, Mikhail A. Kalinin, Sergey Z. Vatsadze, Konstantin P. Volcho, Nariman F. Salakhutdinov

“…The conditions for chromatographic analysis by HPLC-UV were developed, in which the peaks of the enantiomers of all synthesized chiral products were separated, which made it possible to determine the enantiomeric excess of the resulting mixture. It was demonstrated that bispidine-monoterpenoid conjugates can be used as the ligands for diethylzinc addition to chalcone C=C double bond but not as inducers of chirality. …”
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On the Role of ⁴⁰K in the Origin of Terrestrial Life by Giovanni Vladilo

“…The left-handed <inline-formula><math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><semantics><msup><mi>β</mi><mo>−</mo></msup></semantics></math></inline-formula> particles emitted by <inline-formula><math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><semantics><msup><mrow></mrow><mn>40</mn></msup></semantics></math></inline-formula>K are the best candidates to trigger an enantiomeric excess of L-type amino acids via weak nuclear forces in the primitive Earth. …”
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Synthesis, Characterization, and Study of Catalytic Activity of Chiral Cu(II) and Ni(II) Salen Complexes in the α-Amino Acid C-α Alkylation Reaction by Anna S. Tovmasyan, Anna F. Mkrtchyan, Hamlet N. Khachatryan, Mary V. Hayrapetyan, Robert M. Hakobyan, Artavazd S. Poghosyan, Avetis H. Tsaturyan, Ela V. Minasyan, Victor I. Maleev, Vladimir A. Larionov, Armen G. Ayvazyan, Norio Shibata, Giovanni N. Roviello, Ashot S. Saghyan

“…It was found that the introduction of a chlorine atom into the <i>ortho</i>- and <i>para</i>-positions of the phenyl ring of the substrate resulted in an increase in both the chemical yield and the asymmetric induction (<i>ee</i> 66–98%). The highest enantiomeric excess was achieved in the case of a Cu(II) salen complex based on (<i>S</i>,<i>S</i>)-cyclohexanediamine and salicylaldehyde at −20 °C. …”
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New Bifunctional Bis(azairidacycle) with Axial Chirality via Double Cyclometalation of 2,2′-Bis(aminomethyl)-1,1′-binaphthyl by Yasuhiro Sato, Yuichi Kawata, Shungo Yasui, Yoshihito Kayaki, Takao Ikariya

“…The dinuclear chlorido(amine)iridium <b>5</b> can serve as a catalyst precursor for the asymmetric transfer hydrogenation of acetophenone with a substrate to a catalyst ratio of 200 in the presence of KOC(CH₃)₃ in 2-propanol, leading to (<i>S</i>)-1-phenylethanol with up to an enantiomeric excess (ee) of 67%.…”
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Chiral resolution of (R,S)-1-phenylethanol using immobilized lipases in batch stirred tank and recirculated packed bed reactors by Chua, Lee Suan

“…The resolution achieved enantiomeric excess of substrate, ees up to 97 % when molecular sieve 3Ã… was added into the reaction mixture. …”
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Lipase Catalyzed Synthesis of Enantiopure Precursors and Derivatives for β-Blockers Practolol, Pindolol and Carteolol by Morten Andre Gundersen, Guro Buaas Austli, Sigrid Sløgedal Løvland, Mari Bergan Hansen, Mari Rødseth, Elisabeth Egholm Jacobsen

“…The β-blocker (<i>S</i>)-practolol ((<i>S</i>)-<i>N</i>-(4-(2-hydroxy-3-(isopropylamino)propoxy)phenyl)acetamide) was synthesized with 96% enantiomeric excess (<i>ee</i>) from the chlorohydrin (<i>R</i>)-<i>N</i>-(4-(3-chloro-2 hydroxypropoxy)phenyl)acetamide, which was produced in 97% <i>ee</i> and with 27% yield. …”
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Applications of planar-chiral heterocycles in asymmetric catalysis by Tao, Beata, 1973-

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Development and application of palladium-catalyzed carbon-nitrogen bond forming reactions by Wagaw, Seble-Hiwot Teshome, 1971-

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Origin of the Unexpected Enantioselectivity in the Enzymatic Reductions of 5-Membered-Ring Heterocyclic Ketones Catalyzed by <i>Candida parapsilosis</i> Carbonyl Reductases by Byu Ri Sim, Jie Gu, Yvette Ley, Shenggan Luo, Yihan Liu, Qin Chen, Yao Nie, Yi-Lei Zhao

“…In this work, we reported an unexpected enantioselectivity in the enzyme reductions of dihydrofuran-3(2<i>H</i>)-one (<b>DHF</b>) to (<i>S</i>)-tetrahydrofuran-3-ol (<b>DHF-ol</b>, enantiomeric excess: 96.4%), while dihydrothiophen-3(2<i>H</i>)-one substrate (<b>DHT</b>) was unproductive under the same experimental conditions. …”
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System analysis and metabolic engineering of biocatalytic reaction networks : application to indene bioconversion by Stafford, Daniel Edward, 1975-

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A Convenient Route to New (Radio)Fluorinated and (Radio)Iodinated Cyclic Tyrosine Analogs by Maria Noelia Chao, Jean-Michel Chezal, Eric Debiton, Damien Canitrot, Tiffany Witkowski, Sophie Levesque, Françoise Degoul, Sébastien Tarrit, Barbara Wenzel, Elisabeth Miot-Noirault, Audrey Serre, Aurélie Maisonial-Besset

“…Using organotin compounds as key intermediates, [¹²⁵I]5-iodo-L-TIC(OH), [¹²⁵I]6-iodo-L-TIC(OH) and [¹²⁵I]8-iodo-L-TIC(OH) were efficiently prepared with good radiochemical yield (RCY, 51–78%), high radiochemical purity (RCP, >98%), molar activity (Am, >1.5–2.9 GBq/µmol) and enantiomeric excess (e.e. >99%). The corresponding [¹⁸F]fluoro-L-TIC(OH) derivatives were also successfully obtained by radiofluorination of the organotin precursors in the presence of tetrakis(pyridine)copper(II) triflate and nucleophilic [¹⁸F]F⁻ with 19–28% RCY d.c., high RCP (>98.9%), Am (20–107 GBq/µmol) and e.e. (>99%).…”
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