Polymer-Assisted Solution-Phase Synthesis Under Combined Ultrasound and Microwave Irradiation: Preparation of α,β-Unsaturated Esters and Carboxylic Acids, Key Intermediates of Novel Sigma Ligands
摘要:
The optimal conditions to prepare ,-unsaturated methyl esters via Wittig reaction combining polymer-assisted solution-phase synthesis (PASPS) methodology and simultaneous ultrasound and microwave irradiation were established. The effects of temperature, solvent, and irradiation time were discussed. Results clearly indicated the superiority of combined ultrasound and microwave-assisted procedure over microwave-assisted methodology. Moreover, an efficient PASPS procedure to prepare ,-unsaturated carboxylic acids via tandem Wittig olefination and hydrolysis reaction was developed under combined ultrasound and microwave irradiation. Generally, a good conversion of aldehydes to acids was observed. The optimized protocols allowed us to quickly prepare a small collection of either ,-unsaturated esters or carboxylic acids, key intermediates for the drug-discovery process of new sigma ligands.
Free-Radical-Promoted Copper-Catalyzed Decarboxylative Alkylation of α,β-Unsaturated Carboxylic Acids with ICH<sub>2</sub>CF<sub>3</sub> and Its Analogues
作者:Yan Zhu、Juwen Gong、Yonghui Wang
DOI:10.1021/acs.joc.7b01107
日期:2017.7.21
A novel and efficient free-radical-promoted copper-catalyzed decarboxylative alkylation of α,β-unsaturatedcarboxylicacids with ICH2CF3 and its analogues has been developed. This methodology provides a convenient access to the synthesis of allylic trifluoromethyl and β-CF3 ketone containing compounds as well as other biologically useful fluorinated molecules and materials.
Discovery of novel 4-anilinoquinazoline derivatives as potent inhibitors of epidermal growth factor receptor with antitumor activity
作者:Yun-Yun Xu、Si-Ning Li、Gao-Jian Yu、Qing-Hua Hu、Huan-Qiu Li
DOI:10.1016/j.bmc.2013.06.070
日期:2013.10
to a 4-anilinoquinazoline nucleus have been discovered as potential EGFR inhibitors. These compounds proved efficient effects on antiproliferative activity and EGFR–TK inhibitory activity. Especially, N6-((5-bromothiophen-2-yl)methyl)-N4-(3-chlorophenyl)quinazoline-4,6-diamine (5e), showed the most potent inhibitory activity (IC50 = 3.11 μM for Hep G2, IC50 = 0.82 μM for A549). The EGFR molecular docking
Coenzyme A‐Conjugated Cinnamic Acids – Enzymatic Synthesis of a CoA‐Ester Library and Application in Biocatalytic Cascades to Vanillin Derivatives
作者:Martin Dippe、Anne‐Katrin Bauer、Andrea Porzel、Evelyn Funke、Anna O. Müller、Jürgen Schmidt、Maria Beier、Ludger A. Wessjohann
DOI:10.1002/adsc.201900892
日期:2019.12.3
coenzyme A (CoA) with cinnamic acids. The reaction, which is the initial step in the biosynthesis of a multitude of bioactive secondary metabolites, is catalyzed by a promiscuous plant ligase and yields CoA conjugates with different functionalization in high purity and without formation of by‐products. Its applicability in biosynthetic cascades is shown for the direct transformation of cinnamic acids into
Base-Catalyzed Conjugate Addition of Thiols to Indolyl Acrylic Acids and in situ Decarboxylation: An Expedient Synthesis of Functionalized 3-(1-Thio)ethyl-1H-indoles
thio)ethyl-1H-indoles is described herein. This simple procedure in- volves the Michael addition of thiols to 3-indoleacrylic acids fol- lowed by in situ decarboxylation of the Michael adduct in the presence of a catalytic amount of K2CO3 in DMF at 100 °C. The method was found to be fairly general with various thiols and dif- ferent 3-indoleacrylic acids.
Total Synthesis of Calothrixin B
<i>via</i>
an Intramolecular Baylis‐Hillman Cyclization/6π Electrocyclization/Dehydro‐aromatization Sequence and a Specific Oxidative Quinone Formation
作者:Yuancui Liu、Mei Xu、Kaiqiang Xie、Sheng Liu
DOI:10.1002/adsc.202001231
日期:2021.2.2
Baylis−Hillman/6π electrocyclization/dehydroaromatiz‐ation sequence to construct the pentacyclic skeleton. Reduction of the resulting lactam followed by oxidation led to the characteristic quino[4,3‐b]carbazole framework. This intermediate underwent a direct oxidation with high regioselectivity to yield the final product.
从商业上可买到的原料,以原子和步长经济性完成了生物活性生物碱calothrixin B的短暂全合成。关键环化涉及Baylis-Hillman /6π电环化/脱氢芳构化序列,以构建五环骨架。还原生成的内酰胺,然后进行氧化,得到特征性的喹[4,3- b ]咔唑骨架。该中间体进行了具有高区域选择性的直接氧化,以产生最终产物。