Metal-free carbon–carbon cross-couplings between the ion pairs in sulfonium tetraphenylborates
作者:Mei-Li Xu、Wenhua Huang
DOI:10.1016/j.tetlet.2014.05.102
日期:2014.7
A series of sulfonium tetraphenylborates can be readily prepared by the metathesis of sulfonium halides with sodium tetraphenylborates. After heating at 120–150 °C, the sulfonium tetraphenylborates can smoothly undergo the cross-couplings between the tetraphenylborate anions and the sulfonium cations in the absence of a metal catalyst. For carbonylmethyl-, benzyl-, and allylsulfoniums, the corresponding
Demethylative Alkylation of Methionine Residue by Employing the Sulfonium as the Key Intermediate
作者:Qi-Long Hu、Jia-Tian Liu、Jian Li、Yang Ge、Zhendong Song、Albert S. C. Chan、Xiao-Feng Xiong
DOI:10.1021/acs.orglett.1c03241
日期:2021.11.5
Methionine (Met) offers a valuable handle to achieve peptide chemical modification owing to its unique thioether functional group. In contrast with cysteine, the site-selective functionalization of the hydrophobic and redox-sensitive thioether motif on peptides is still challenging, and strategies for diversification on the Met residue are rarely disclosed. Herein we report a transition-metal-free
由于其独特的硫醚官能团,蛋氨酸 (Met) 为实现肽化学修饰提供了一种有价值的方法。与半胱氨酸相比,肽上疏水和氧化还原敏感的硫醚基序的位点选择性功能化仍然具有挑战性,并且很少公开 Met 残基多样化的策略。在这里,我们报告了一种无过渡金属和氧化还原中性方法,用于具有底物多样性的 Met 多样化,可用于合成环肽。
[EN] PYRIDAZINES HERBICIDAL COMPOUNDS<br/>[FR] COMPOSÉS HERBICIDES DE PYRIDAZINES
申请人:SYNGENTA CROP PROTECTION AG
公开号:WO2020169604A1
公开(公告)日:2020-08-27
Compounds of the formula (I) wherein the substituents are as defined in claim 1, useful as a pesticides, especially as herbicides.
Compounds of the formula (I) wherein the substituents are as defined in claim 1, useful as a pesticides, especially as herbicides.
化合物的分子式(I),其中取代基如权利要求书中定义的那样,作为农药是有用的,特别是作为除草剂。
Conformationally defined piperazine bis(N-oxides) bearing amino acid derived side chains
作者:Ian A. O’Neil、Andrew J. Potter、J. Mike Southern、Alexander Steiner、James V. Barkley
DOI:10.1039/a806901h
日期:——
The preparation of a number of piperazine derivatives bearing amino acid substituents on the nitrogen is described; these compounds undergo oxidation with MCPBA to yield bis(N-oxides) in which both oxygen atoms are axially orientated and hydrogen bonded to the amide NHs, giving highly defined conformations to the molecules; the structure of the valine derivative (8c) was confirmed by X-ray analysis.