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Monomers Containing Different Multiple Bonds (Functionally Unsymmetrical Monomers)
Published in George B. Butler, Cyclopolymerization and Cyclocopolymerization, 2020
Various cyclopolymerizable monomers were synthesized by reaction of acrolein as a diene with several vinyl compounds as dienophiles.21 Thus, a series of N-(2,3-dihydro-2-pyranyl)carbamic acid esters and ureas were prepared by addition of various N-vinylcarbamic acid esters and N-vinylureas to α,β-unsaturated carbonyl derivatives, and hydrolyzed to CH2(CH2CHO)2 and CH3CO(CH2)3CHO. Hydrogenation of these monomers led to the cyclized tetrahydropyran structures.
Synthesis and catalytic performance of a soluble asymmetric zinc phthalocyanine
Published in Journal of Coordination Chemistry, 2019
Shanlei Guo, Dongni Li, Bo Gao, Yanhui Li, Haotian Zhang, Yanwei Li, Qian Duan
4-Decyloxy phthalonitrile (568 mg, 2.0 mmol) and 4-[2-(2-bromoethoxy-pyran)] phthalonitrile (182 mg, 0.67 mmol) in the presence of Zn(CH3CO2)2 (240 mg, 1.10 mmol), 1-pentanol (10 mL), and DBU (0.75 mL) were refluxed for 48 h under nitrogen. Methanol (50 mL) was added after the reaction completed. The residue was treated with p-toluenesulfonic acid (0.30 g, 1.70 mmol) in a mixture of methanol and DCM (10 mL, 1:2, v/v) to remove the tetrahydropyran protecting group. The solvent was removed by rotary evaporation, and the residue was washed with methanol. The crude product was purified, getting asymmetrical Pc 72.41 mg. Yield: 10%. Anal. Calcd. for C64H80N8O5Zn (%): C, 69.45; H, 7.29; N, 10.12. Found: C, 69.30; H, 7.32; N, 10.24. HRMS (m/z): calcd for C64H80N8O5Zn: 1104.55; Found: 1104.50 [M + H]+. FT-NIR (KBr, cm−1): 3404 (νOH), 2953 (νCH3), 2853 (νCH2), 1605 (νC = C), 1341 (νC–N). 1H NMR (500 MHz, DMSO-d6), δ ppm: 9.06 (4H, Ar-H), 8.68 (4H, Ar-H), 7.69 (4H, Ar-H), 5.19 (1H, –OH), 4.27 (10H, –OCH2–), 1.31–2.04 (48H, –CH2–), 0.91 (9H, –CH3).
6-(2-Morpholinoethyl)-thiazolo[3,2-a]pyrimidin-5-one: A novel scaffold for the synthesis of potential PI3kα inhibitors
Published in Egyptian Journal of Basic and Applied Sciences, 2018
Ahmed R. Ali, Eman R. El-Bendary, Mariam A. Ghaly, Ihsan A. Shehata
We tried to investigate the possible causes for the decrease in the activity of screened compounds. A possible cause of the decrease in inhibitory activity of the screened compounds may be due to the non-coplanarity. Compounds 4a and 4b were energy minimized using MMFF94x and after that aligned using MOE.2009.10 [37]. It was found that a morpholine moiety, attached to thiazolopyrimidinone ring system through two carbon spacer, is not co-planar with the central core, Fig. 1. Previous case was reported with the same enzymes and was responsible for the decrease in activity. It was found that the inclusion of the tetrahydropyranyl scaffold instead of dihydropyranyl into pyrazolopyrimidine derivatives was associated with a great decrease in both mTOR and PI3K potency. This decline in activity was explained by the differing minimum energy conformation of these two cycles. The dihydropyran (DHP) ring was found to be co-planar with the pyrazolopyrimidine core, whereas the tetrahydropyran (THP) ring is rotated about 90° out-of-plane with the core [38].
Actinide–lanthanide co-extraction by rigidified diglycolamides
Published in Solvent Extraction and Ion Exchange, 2018
Elena Macerata, Annalisa Ossola, Walter Panzeri, Marco Giola, Federica Faroldi, Dario Alberto Tinonin, Andrea Mele, Alessandro Casnati, Mario Mariani
Three diglycolamides (1–3) rigidified by the introduction of a pyran and tetrahydropyran ring were studied for the An and Ln co-extraction from simplified synthetic feeds. In the case of ligands 1 and 2, the less basic character of the central oxygen atom in the aromatic pyran ring resulted in a very low extraction efficiency. Distribution ratios for compound 3 are higher than those obtained for TODGA under the same experimental conditions and also than those of other substituted and rigidified (furan and tetrahydrofuran) DGAs reported in the literature. However, decreasing D values were obtained for ligand 3 with increasing the nitric acid concentration owing to a higher tendency to form nitric acid adducts. Moreover, for the substituted and rigidified DGAs, no significant improvements in separation factors were reported in the literature with respect to TODGA, while for the three carboxamide extractants under study, lower SFEu/Am values were found, close to 1 for ligands 1 and 2 and around 4 for ligand 3. Similarly to TODGA, ligand 3 shows fast kinetics, a lower affinity toward the lightest lanthanides, and an easy metal cation recovery. In fact, an effective back-extraction could be easily achieved by using diluted nitric acid solutions. Finally, HPLC–MS analyses enabled us to investigate the ligand stability in the presence of 1-octanol and nitric acid. The formation of octyl ester and ether by-products is coherent with what reported in the literature and can reasonably lead to a loss of extraction efficiency.