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21.
3-Methylindole is acylated regioselectively at the methyl group when treated with a variety of acyl chlorides in 1,2-dichloroethane in the presence of AlCl(3), affording a mild and direct method for the synthesis of 3-(2-oxoalkyl)indoles. The product formation in this one-pot reaction largely depends on the conditions of the reaction employed. The methodology does not require protection-deprotection steps and is amenable for the scale-up synthesis of these indole derivatives.  相似文献   
22.
Hydroxy-rhodium catalyzed dimerization of various cyclic enones to the corresponding α-enone adducts is developed. The key feature of this method is that the base-sensitive, highly substituted enones also undergo dimerization and the resultant products are obtained in moderate to good yields.  相似文献   
23.
Sakram  B.  Ashok  K.  Rambabu  S.  Sonyanaik  B.  Ravi  D. 《Russian Journal of General Chemistry》2017,87(8):1794-1799
Russian Journal of General Chemistry - Synthesis of substituted 1,8-naphthyridines based on 2-aminonicotinaldehyde under mild conditions is studied. Out of three electrophilic iodine sources (I2,...  相似文献   
24.
25.
We have synthesised new Mn-MOF@Pi composite by encapsulation of piperidine in desolvated Mn-MOF and investigated its catalytic performance in Knoevenagel condensation reaction. The newly developed composite is compatible with various aromatic aldehydes and converting them to the desired Knoevenagel condensation products in good yields and selectivity. Furthermore, composite Mn-MOF@Pi is reusable and shows good catalytic activity than native MOF.  相似文献   
26.
Indole based novel small molecules were designed as potential anticancer agents. Multi step synthesis of these compounds was carried out by using Pd/C–Cu mediated coupling–cyclization strategy as a key step. The single crystal X-ray diffraction study was used to confirm the molecular structure of a representative compound unambiguously. Many of these compounds were evaluated for their anti-proliferative properties in vitro against six cancer cell lines as well as noncancerous cells. All these compounds showed selective growth inhibition of cancer cells and several of them were found to be promising with IC50 values in the range of 0.1–1.2 μM, comparable to the known anticancer drug doxorubicin.  相似文献   
27.
An efficient and eco-friendly method for the synthesis of substituted pyrroles has been developed via ruthenium-catalyzed multicomponent reaction of ketone, amine, and ethylene glycol in PEG-400 as solvent medium without using any external ligand. The catalytic system and solvent can be recycled with the same, as well as different, ketones with minimum loss of Ru-catalyst activity.  相似文献   
28.
Antimicrobial resistance is on the rise, and there aren’t enough new treatments to combat it. This might send the modern world back to the pre-antibiotic age. The molecular hybrids of pyrazolo[3,4-b]pyridine and triazole have been designed, synthesized, and analyzed for their drug-like molecule nature and in vitro analyses for their inhibition potentials against S. aureus and K. pneumoniae. The compounds 24 and 27 have been identified as the high potential molecules in this series based on in vitro experiments. Compound 24 has zone of inhibition values of 15 ± 0.82 mm and 14 ± 0.7 mm, whilst compound 27 has zone of inhibition values of 18 ± 0.95 mm and 16 ± 0.82 mm against S. aureus and K. pneumoniae, respectively. MIC and MIB values for compounds 24 and 27 against S. aureus and K. pneumoniae are 0.25 and 0.5, respectively.  相似文献   
29.
The magnetic and57Fe Mössbauer studies in melt-spun RuFeSi show that in spite of the differences in the Xac responses between the melt-spun and annealed specimens, which have very different atomic order/disorder, the microscopic details of the Fe spin dynamics are similar. The melt-spun sample does not show reentrant like bulk magnetic behaviour in contrast to the annealed specimens.  相似文献   
30.
This Review discusses the various methods for functionalizing pyridine and quinoline scaffolds, including direct selective metalation (DoM), halogen/metal exchange reactions, Li, Mg, and Zn insertion, and trans-metalation approaches, which are then followed by cross-coupling reactions of the Kumada or Negishi types. Selective deprotonation of aryl or pyridyl/quinolinyl derivatives can be performed using n-BuLi, LDA, and TMP-based different organolithium, -magnesium, and -zinc reagents. The functionalized pyridine and quinoline-based heterocyclic compounds were prepared by selectively deprotonating with presenting a directing functional group substituted pyridine/quinoline analogues in the presence of TMP-bases (TMP−Li, Mg, Zn reagents). Different aryl or alkyl Li, Mg, and Zn reagents with electron-donating and electron-withdrawing substituents undergo transition metal-catalyzed C(sp2)−C(sp2) and C(sp2)−C(sp3) types of cross-coupling reactions with pyridine/quinoline halides under mild conditions with the sustainable process producing complex N-heterocycles. Using moderate and sustainable reaction conditions, sensitive functional group tolerance, and inexpensive and low toxic chemicals, highly functionalization of pyridine and quinoline-based bioactive therapeutic scaffolds and natural products was accomplished. Therefore, in this article, we provide a succinct overview of the numerous synthetic strategies and practical methods used by various authors between 2010 and 2023 to functionalize pyridine and quinoline analogues using diverse Li, Mg, and Zn organometallic reagents.  相似文献   
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