Synthesis and Anti-bacterial Properties of Mono-carbonyl Analogues of Curcumin
作者:Guang Liang、Shulin Yang、Lijuan Jiang、Yu Zhao、Lili Shao、Jian Xiao、Faqing Ye、Yueru Li、Xiaokun Li
DOI:10.1248/cpb.56.162
日期:——
The synthesis of three series of curcumin analogues with mono-carbonyl is described. Their in vitro anti-bacterial activities against seven Gram-positive and Gram-negative bacteria were tested and the effect of substituents on the aryl ring and the space structure of the linking strain were discussed. It was observed that part of the derivatives displayed significant activity when compared with curcumin and most of them exhibited activity against the ampicillin-resisted Enterobacter cloacae. Compounds A12, B09, B13, B14 and C09 show remarkable antibacterial activity in vitro. The result showed that heterocycle or long-chain substituents may enhance the activity of curcumin analogues.
作者:Kelsey L. Horvath、Christopher G. Newton、Kimberley A. Roper、Jas S. Ward、Michael S. Sherburn
DOI:10.1002/chem.201900550
日期:2019.3.15
compounds of the tetravinylethylene (TVE) family is reported. Ramirez‐type dibromo‐olefination of readily accessible penta‐1,4‐dien‐3‐ones generates 3,3‐dibromo[3]dendralenes, which undergo twofold Negishi, Suzuki–Miyaura or Mizoroki–Heck reactions with a wide variety of olefinic coupling partners. This route delivers a broad range of unsymmetrically substituted tetravinylethylenes with up to three
Supramolecular polymeric aggregation behavior and its impact on catalytic properties of imidazolium based hydrophilic ionic liquids
作者:Shoaib Muhammad、Muhammad Naveed Javed、Firdous Imran Ali、Ahmed Bari、Imran Ali Hashmi
DOI:10.1016/j.molliq.2019.112372
日期:2020.2
(ILs) self-assemble to form supramolecularpolymeric clusters/aggregates. The aggregation behavior of ILs influences its activity in the organic synthesis. However, the precise role of ILs in organic reactions is still unknown. It is, therefore, important to comprehend the supramolecularpolymeric aggregation behavior of ILs. We are exploring the supramolecularpolymeric aggregation behavior of ILs
离子液体(ILs)自组装形成超分子聚合物簇/聚集体。IL的聚集行为影响其在有机合成中的活性。但是,IL在有机反应中的确切作用仍是未知的。因此,重要的是要理解IL的超分子聚合聚集行为。我们正在使用电喷雾电离质谱(ESI-MS)探索IL的超分子聚合聚集行为。我们已经合成了四个亲水性IL(1-4),并研究了它们的聚集行为及其对碳-碳键形成(Knoevenagel和Claisen-Schmidt缩合)催化活性的影响。在这里,我们表明IL的聚集行为取决于阳离子和阴离子的类型和性质。ESI-MS(-ve)光谱揭示了两种不同类型的聚集,即[C n A n + 1 ] -和[A 2 + H + ] -。我们发现,催化活性随[C n A n + 1 ] -超分子聚集的增加而增加。因此,在IL中获得的最高收率的产品显示出阴离子-阴离子聚集的减少[A 2 + H +] – ESI-MS中的丰度。我们预计我们
Palladium(II)-Catalyzed Substituted Pyridine Synthesis from α,β-Unsaturated Oxime Ethers via a C–H Alkenylation/Aza-6π-Electrocyclization Approach
for multisubstituted pyridines from β-aryl-substituted α,β-unsaturated oxime ethers and alkenes via Pd-catalyzed C–H activation has been developed. Systematic optimization of catalyst ligands revealed that sterically hindered pyridines increased the reactivity. Mechanistic studies suggested that the products are formed by Pd-catalyzed β-alkenylation of α,β-unsaturated oxime followed by aza-6π-electrocyclization
Novel CuBr·SMe<sub>2</sub>Catalyzed Conjugate Addition of 3-Trimethylsilyl-1-propenylzirconocene to Divinylketones. Stereoselective Synthesis of Polysubstituted Cyclohexanones
作者:Xian Huang、Jinhong Pi
DOI:10.1055/s-2003-37525
日期:——
Conjugate addition of (E)-3-trimethylsilyl-1-propenylziroconocene to (E,E)-divinylketones in the presence of catalytic amount of CuBr·SMe2 affords (E)-allylsilanes containing (E)-α,β-unsaturated carbonyl moiety under mild conditions with good yield. They undergo highly stereocontrolled silicon-assisted intramolecular cylization when treated with TiCl4 leading to polysubstituted cyclohexanones.