Burkholderia cepacia lipase is an excellent enzyme for the enantioselective hydrolysis of β-heteroaryl-β-amino esters
摘要:
The enantioselective (E > 200) lipase PS-catalysed hydrolysis of beta-heteroaryl-beta-amino esters is described. The reactions were performed with H2O (0.5 equiv) in either diisopropyl ether or tert-butyl methyl ether at 25 degrees C. The resulting beta-heteroaryl-substituted beta-amino acid enantiomers were formed in high enantiomeric excess (ee >= 97%) and in good yield (>= 40%). (c) 2009 Elsevier Ltd. All rights reserved.
Tetrasubstituted 1,3-Enynes by Gold-Catalyzed Direct C(sp<sup>2</sup>)–H Alkynylation of Acceptor-Substituted Enamines
作者:Chunyu Han、Xianhai Tian、Huili Zhang、Frank Rominger、A. Stephen K. Hashmi
DOI:10.1021/acs.orglett.1c01486
日期:2021.6.18
A gold-catalyzed synthesis of tetrasubstituted 1,3-enynes fromhypervalent iodine(III) reagents and activated alkenes is reported. This reaction involves an in situ formed alkynyl Au(III) species and a subsequent direct C(sp2)–H functionalization of alkenes, offering 26 enynes in 62–92% yield with excellent functional group tolerance.
An acid promoted cyclisation of benzylidene-modified tetramic acid and various enamines followed by MnO2 oxidation afforded the corresponding C2-symmetric and unsymmetric lactam-fused pyridines in enantiomerically pure forms.
Synthesis of acyloxy-2<i>H</i>-azirine and sulfonyloxy-2<i>H</i>-azirine derivatives <i>via</i> a one-pot reaction of β-enamino esters, PIDA and carboxylic acid or sulfonic acid
作者:Pan Tang、Long Wen、Hao-Jie Ma、Yi Yang、Yan Jiang
DOI:10.1039/d2ob00364c
日期:——
acyloxy-2H-azirine and sulfonyloxy-2H-azirine derivatives was synthesized in moderate to good yields. This represents the first oxidative sulfonyloxylation/azirination of β-enamino esters with PIDA and sulfonic acid for access to sulfonyloxy-2H-azirine. Hypervalent iodine reagents enable cascade C–O/C–N bond formation. Furthermore, a possible reaction pathway was proposed based on the experimental
研究了 PIDA 介导的 β-烯氨基酯的氧化酰氧基化/氮丙啶化和磺酰氧基化/氮丙啶化。以中等至良好的收率合成了一系列官能化的 acyloxy-2 H -azirine 和 sulfonyloxy-2 H -azirine 衍生物。这代表了 β-烯氨基酯与 PIDA 和磺酸的第一次氧化磺酰氧基化/氮丙啶化以获得磺酰氧基-2 H-氮杂环丙烷。高价碘试剂能够形成级联 C-O/C-N 键。此外,根据实验结果提出了可能的反应途径。
Uracil derivatives and pesticides containing the same as active
申请人:Nissan Chemical Industries Ltd.
公开号:US05116404A1
公开(公告)日:1992-05-26
The present invention provides novel uracil derivatives and pesticides which contain the novel uracil derivatives as an active ingredient, and exhibit preventing and controlling effects against harmful living things, especially agricultural insect pests, sanitary insect pests, stored product insect pests, house insect pests and veterinary insect pests at a very low drug-concentration.