- A Novel Synthesis of 1,2,3-Benzotriazinones from 2-(o -Aminophenyl)oxazolines
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1,2,3-Benzotriazinones were synthesized in excellent yields by the reaction of 2-(o-aminophenyl)oxazolines and isoamyl nitrite in methanol. The crystal structure of the acetyl derivative of one of the 1,2,3-benzotriazinones provided additional support for
- Rocha-Alonzo, Fernando,Chávez, Daniel,Ochoa-Terán, Adrián,Morales-Morales, David,Velázquez-Contreras, Enrique F.,Parra-Hake, Miguel
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- Enantioselective Diels-Alder Reaction Using Chiral Mg Complexes Derived from Chiral 2-2-Alkyl- Or 2-[2-[(Arylsulfonyl)amino]phenyl]-4-phenyl-1,3-oxazoline
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Magnesium complexes derived from (R)-2-[2-[(alkyl- or (R)-2-[2-[(arylsulfonyl)amino]phenyl]-4- phenyl-1,3-oxazolines and methylmagnesium iodide were found to be efficient Lewis acid catalysts for the Diels-Alder reaction of 3-alkenoyl-1,3-oxazolidin-2-one with cyclopentadiene. Chiral ligands were easily prepared from readily available D-phenylglycinol in good yields. The reaction of 3-acryloyl-1,3-oxazolidin-2-one with cyclopentadiene catalyzed by a stoichiometric amount of the Lewis acid gave exclusively the endo-cycloaddition product in up to 92% ee. The sulfonamide group on the chiral ligand strongly influenced the enantiofacial selectivity: the use of a toluene-, benzene-, 1- or 2-naphthalene-, or methanesulfonamide group in the chiral ligand gave the endo-(2R)- cycloaddition product, while a trifluoromethanesulfonamide group predominantly gave its enantiomer, the endo-(2S)-cycloaddition product, in 65% ee. The scope and limitations of the catalytic effect of chiral Mg(II) complexes on the enantioselectivity of the Diels-Alder reaction were investigated. The reaction mechanism of the Mg(II)-catalyzed reaction is also discussed on the basis of the experimental results.
- Ichiyanagi, Tsuyoshi,Shimizu, Makoto,Fujisawa, Tamotsu
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- Significant Enhancement of Circularly Polarized Luminescence Dissymmetry Factors in Quinoline Oligoamide Foldamers with Absolute Helicity
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When S- or R- oxazolylaniline enantiomers were attached to achiral quinoline oligoamide foldamers (QOFs), a single diastereomerically pure P- or M-handed foldamer was observed and exhibits negative or positive circularly polarized luminescence with the em
- Zheng, Dan,Zheng, Lu,Yu, Chengyuan,Zhan, Yulin,Wang, Ying,Jiang, Hua
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- Clay catalyzed conversion of isatoic anhydride to 2-(o-aminophenyl)oxazolines
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A simple and environmentally safe procedure for the preparation of 2-(o-aminophenyl)oxazolines from isatoic anhydride is presented. A series of chiral derivatives of the title compound is prepared in moderate yield via natural kaolinitic clay catalyzed re
- Gajare, Anil S.,Shaikh, Nadim S.,Jnaneshwara, Gowda K.,Deshpande, Vishnu H.,Ravindranathan, Thottappilli,Bedekar, Ashutosh V.
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- Nicotinamide compound containing chiral oxazoline and application of same as agricultural bactericide
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The invention relates to a novel nicotinamide compound containing chiral oxazoline and application of the compound as an agricultural bactericide. The compound has a chemical structural formula as shown in a formula (I) which is described in the specifica
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Paragraph 0027; 0028; 0029
(2017/08/27)
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- Design, Synthesis, Fungicidal Activity, and Unexpected Docking Model of the First Chiral Boscalid Analogues Containing Oxazolines
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Chirality greatly influences the biological and pharmacological properties of a pesticide and will contribute to unnecessary environmental loading and undesired ecological impact. No structure and activity relationship (SAR) of enantiopure succinate dehydrogenase inhibitors (SDHIs) was documented during the structure optimization of boscalids. On the basis of commercial SDHIs, oxazoline natural products, and versatile oxazoline ligands in organic synthesis, the first effort was devoted to explore the chiral SDHIs and the preliminary mechanism thereof. Fine-tuning furnished chiral nicotinamides 4ag as a more promising fungicidal candidate against Rhizoctonia solani, Botrytis cinerea, and Sclerotinia sclerotiorum, with EC50 values of 0.58, 0.42, and 2.10 mg/L, respectively. In vivo bioassay and molecular docking were investigated to explore the potential in practical application and plausible novelty in action mechanism, respectively. The unexpected molecular docking model showed the different chiral effects on the binding site with the amino acid residues. This chiral nicotinamide also featured easy synthesis and cost-efficacy. It will provide a powerful complement to the commercial SDHI fungicides with the introduction of chirality.
- Li, Shengkun,Li, Dangdang,Xiao, Taifeng,Zhang, Shasha,Song, Zehua,Ma, Hongyu
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p. 8927 - 8934
(2016/12/07)
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- The novel reaction of ketones with o-oxazoline-substituted anilines
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A variety of ketones react with o-oxazoline-substituted anilines in the presence of catalytic amount of p-toluenesulfonic acid in dry n-butanol to form 4-amino-substituted quinolines or 4-quinolones in fair to good yields.
- Luo, Fen-Tair,Ravi, Vija K.,Xue, Cuihua
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p. 9365 - 9372
(2007/10/03)
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- Enantioselective Diels-Alder reaction using chiral Lewis acid prepared from Grignard reagent and a chiral 2-(2-p-toluenesulfonylamino)phenyl-4- phenyloxazoline
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Enantioselective Diels-Alder reaction was conducted successfully using a chiral magnesium complex prepared from Grignard reagent and a chiral 2-(2-p- toluenesulfonyl-amino)phenyl-4-phenyloxazoline derived from easily available D-phenylglycine as a chiral
- Fujisawa,Ichiyanagi,Shimizu
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p. 5031 - 5034
(2007/10/02)
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