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211.
A short and efficient synthetic approach for brivaracetam has been accomplished via two different routes which utilize Pd-catalyzed oxidative cyclization and ring-closing metathesis (RCM) as the key reaction. These two routes are novel, simple, scalable and rely on (E)-pent-2-en-1-ol and valeraldehyde as a commercially available starting material to yield brivaracetam with good overall yield. 相似文献
212.
Dattatraya D. Gaikwad Umakant D. Pawar Sadhana L. Chavan Chandrakant D. Pawar Dattatraya N. Pansare Rohini N. Shelke Santosh L. Chavan Ashok M. Zine 《Journal of heterocyclic chemistry》2020,57(4):1925-1935
A series of novel imidazo[1,2-b]pyridazin-3-yl acetamide derivatives (9a-9j) were synthesized from a 3,6-dichloropyridazine. We have developed a simple strategy for the synthesis of functionally diverse imidazole, and pyridiazine derivatives were reported via a series of steps. The work involves bicyclic imidazo-pyridazine ring formation, halogenation, cynation, hydrolysis, peptide coupling, and Buchwald reaction. The structure of the synthesized compounds was confirmed by IR, 1H NMR, 13C NMR,19F NMR, mass spectra, and elemental analysis, and purity is checked by HPLC. All synthesized compounds were screened for anticancer activity against A-549 and Du-145 cancer cell lines by MTT assay. The preliminary bioassay suggests that most of the compounds show anti-proliferation with different degrees; doxorubicin was used as positive control. The synthesized compound shows IC50 values in the range of 1.74μM to 16.17μM in both cell lines. The compounds 9e , 9g , and 9h were active compared with doxorubicin in both the cell lines. The compounds having cyclopentyl ring are active compared with higher and lower carbon analogues. 相似文献
213.
214.
Saha Asit Sarkar Satyajit Banerjee Santo Mondal Kajal Kumar 《The European physical journal. Special topics》2020,229(6-7):979-988
The European Physical Journal Special Topics - We propose a dynamical system governing from the nonlinear extension of the electrostatic ion-acoustic waves (IAWs) under the influence of external... 相似文献
215.
Two pyridine-based ligands (N-((pyridin-2-yl) methyl) pyridin-2-amine) L1 and (N-((pyridin-2-yl) methylene) pyridin-2-amine) L2 are explored in present work which are inexpensive, effective and environmentally benign in their properties. These have been utilized for C-N cross coupling reaction resulting in N-arylation. The N-arylation of indole, imidazole and triazole have been successfully carried out with different aryl and heteroaryl halides using these ligands. 相似文献
216.
Sham Ravindranath Shi-Qing Wang M. Olechnowicz V. S. Chavan R. P. Quirk 《Rheologica Acta》2011,50(2):97-105
This work aims to elucidate how molecular parameters dictate the occurrence of inhomogeneous cohesive failure during step
strain and large amplitude oscillatory shear (LAOS) respectively in entangled polymer mixtures. Based on three well-entangled
polybutadiene (PB) mixtures, we perform simultaneous rheometric and particle-tracking velocimetric (PTV) measurements to illustrate
how the slip length controls the degree of shear banding. Specifically, the PB mixtures were prepared using the same parent
polymer (M
w ∼ 106 g/mol) at 10 wt.% concentration in respective polybutadiene solvents (PBS) of three different molecular weights 1.5, 10,
and 46 kg/mol. After step strain, the entangled PB mixture with PBS-1.5 K displayed interfacial failure whereas the PB mixture
with PBS-10 K showed bulk failure, demonstrating the effectiveness of our strategy to suppress wall slip by controlling PBS’
molecular weight. Remarkably, the PBS-46K actually allows the elastic yielding to occur homogeneously so that no appreciable
macroscopic motions were observed upon shear cessation. PBS is found to play a similar role in LAOS of these three PB mixtures.
Finally, we demonstrate that in case of the slip-prone mixture based on PBS-1.5 K the interfacial failure could be drastically
reduced by use of shearing plates with considerable surface roughness. 相似文献
217.
Jose Manu Kumari Mahitha Karunakaran Remya Shukla Satyajit 《Journal of Sol-Gel Science and Technology》2015,75(1):38-44
Journal of Sol-Gel Science and Technology - Highly crystalline nanotubes/nanoplates of pure and Ag-doped anatase-titania (TiO2) having high aspect-ratio have been synthesized, without the... 相似文献
218.
219.
Chavan Pramod V. Pandit Kapil S. Desai Uday V. Wadgaonkar Prakash P. Nawale Laxman Bhansali Sujit Sarkar Dhiman 《Research on Chemical Intermediates》2017,43(10):5675-5690
Research on Chemical Intermediates - A series of spirochromene-tethered 1,2,3-triazoles (1,2,3-triazolylspirochromenes) were designed and synthesized via click-chemistry-based one-pot... 相似文献
220.
A facile, mild, and efficient methodology for the ionic Diels–Alder reaction of acetals of α,β‐unsaturated ketones and aldehydes as dienophiles with various 1,3‐dienes employing MgBr2 as the Lewis acid catalyst to furnish corresponding Diels–Alder adducts at ambient temperature is described. 相似文献