4,4-Difluoropyrazolidine-3,5-dione was synthesized as a precursor for the corresponding pyrazolinedione, envisioned as a photochemical source of difluorocarbene. However, this azo compound proved to be far too unstable. In contrast, 10,10-difluorobicyclo[4.3.1]deca-1,3,5-triene, readily synthesized from indane, was found to be a practical source of difluorocarbene for photochemical as well as thermal cyclopropanation reactions. (C) 2002 Elsevier Science B.V All rights reserved.
Design, synthesis and biological evaluation of spiropyrimidinetriones oxazolidinone derivatives as antibacterial agents
作者:Asher M. Siddiqui、Jitendra A. Sattigeri、Kalim Javed、Syed Shafi、M. Shamim、Smita Singhal、Zubbair M. Malik
DOI:10.1016/j.bmcl.2018.02.055
日期:2018.4
positive bacteria. We report herein a novel class of spiropyrimidinetrione oxazolidinone derivatives as novel antibacterialagents. Key step towards the synthesis of title compounds involved the use of tert-amino reaction with [1,5]-hydride shift leading to the new CC bond formation. Compound 30n has demonstrated potent antibacterial activity against a panel of Gram-positive microbial strains including
Bei den vor längerer Zeit versuchten Darstellungen des unsubstituierten monomeren 3,5‐Pyrazolidindions (2) konnte allenfalls ein Polymer der Zusammensetzung [C3H4O2N2]x isoliert werden. Erst die Cyclisierung von Malonsäureethylesterhydrazid in methanolischer Lösung unter Zusatz von Natriummethanolat führte kürzlich zum Erfolg. Der Strukturbeweis des so gewonnenen Produktes konnte über die üblichen analytischen
很久以前,在尝试表示未取代的单体 3,5-吡唑烷二酮 (2) 时,最多可以分离出一种具有 [C3H4O2N2] x 组成的聚合物。最近只有加入甲醇钠在甲醇溶液中环化丙二酸乙酯才取得成功。可以使用通常的分析方法提供以这种方式获得的产品的结构证据;也可以初步检测酰肼功能和活性亚甲基。2的分子几何形状通过X射线结构分析确定。
Synthesis and antimicrobial evaluation of the novel heteroannulated furo[3′,2′:6,7]chromeno[2,3‐b]pyridines: Part 1
作者:Magdy A. Ibrahim、Sami A. Al‐Harbi、Esam S. Allehyani
DOI:10.1002/jhet.4082
日期:2020.10
The chemical behavior of 4,9‐dimethoxy‐5‐oxo‐5H‐furo[3,2‐g]chromene‐6‐carbonitrile (1) was investigated toward some acyclic and cyclic active methylene ketones namely acetylacetone, ethyl acetoacetate, ethyl benzoylacetate, acetoacetanilide, dimedone, indanedione, pyrazolidine‐3,5‐dione and 5‐methyl‐2‐phenyl‐2,4‐dihydro‐3H‐pyrazol‐3‐one, barbituric acid and 1‐allylthiobarbituric acid, and hippuric
研究了4,9-二甲氧基-5-氧代-5 H-呋喃[3,2 - g ]亚甲基-6-腈(1)对一些无环和环状活性亚甲基酮的反应,即乙酰丙酮,乙酰乙酸乙酯,乙基苯甲酰乙酸,乙酰乙酰苯胺,二甲酮,茚二酮,吡唑烷-3-,5-二酮和5-甲基-2-苯基-2-,4-二氢-3 H-吡唑-3-酮,巴比妥酸和1-烯丙基硫代巴比妥酸和马尿酸。通过4,9-二甲氧基-5-氧代-5 H-呋喃[3,2 - g ]色烯-6-腈(1的级联反应)有效地合成了多种新型的异环呋喃铬吡啶)和碳亲核试剂。根据新产品的分析和光谱数据推断其结构。
Profiling the reactivity of cyclic C-nucleophiles towards electrophilic sulfur in cysteine sulfenic acid
作者:Vinayak Gupta、Kate S. Carroll
DOI:10.1039/c5sc02569a
日期:——
Oxidation of a protein cysteine thiol to sulfenic acid, termedS-sulfenylation, is a reversible post-translational modification that plays a crucial role in regulating protein function and is correlated with disease states.
as a green medium, using the cyclic voltammetry and controlled-potential coulometry techniques. The results obtained indicated that the oxidized forms of these catechols (2a and 2b) participated in the Michael addition reactions with pyrazolidine-3,5-dione (3a), and converted, via an ECEC mechanism, to their corresponding benzofurans (7a and 7b). In this work, some new benzofuran derivatives were synthesized