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991.
Yang-Gen Hu Shang-Jun Yang Ming-Wu Ding 《Phosphorus, sulfur, and silicon and the related elements》2013,188(10):1933-1939
4H-Imidazol-4-ones 4 or 4(3H)-quinazolinones 8 were synthesized by base catalytic reactions of 2-mercaptobenzothiazole with carbodiimides 2 or 6, respectively, which were obtained via aza-Wittig reaction of iminophosphorane 1 or 5 with aromatic isocyanates. 4 and 8 exhibited fungicidal activity. 相似文献
992.
Abstract The chemical modified β-cyclodextrin(CD), which bears a fluorophore group — N,N-dimethylamino-chalcone (DMAC), was synthesized. The self-inclusion behavior of this compound in aqueous solution and in alcohol/water mixed solvents was investigated in detail, and compared with the inclusion system of non-modified CD with free DMAC molecule. The results showed that a deep self-inclusion complex was formed for this compound in aqueous solution and had the ability to recognize different organic molecules by two fully different modes: “in-out” and “co-inclusion” mechanisms. The inclusion behavior of these systems in various ratio of alcohol/water mixture as solvents was investigated. The results indicated that the self-inclusion complex has a higher stability in alcohol/water mixed solvents than that in the case of non-modified CD. The chalcone group appended at β-CD enabled the host as a sensitive probe to study the inclusion behavior of CD. 相似文献
993.
Polyoxyethylene macromers were synthesized by polymerization of ethylene oxide in dimethylsulfoxide by using potassium napthalide in tetrahydrofuran as initiator, followed by termination with methacroyl chloride. Potassium naphthalide is more active as an initiator than sodium naphthalide. The initiator in this case was confirmed to be of the monoanionic type. The molecular weight of the macromers can be varied from 2 × 103 to 1.2 × 104with Mw/Mn = 1.07-1.12. The macromers were characterized by UV, IR, and 1H NMR, and copolymerized with butyl acrylate, methyl acrylate, or methyl methacrylate. The grafting efficiency can reach about 90%. The graft copolymers were purified by extractions and characterized by GPC, IR, and a Bruss membrane osmometer. The average grafting number of the copolymers varied from 10 to 15. 相似文献
994.
995.
Chen J.-J. Huang P.-Y. Yang Z.-S. Cai X.-Z. Shi Y. Hu W.-Y. Zhang X.-H. Chai H.-F. Huang Z.-Y. 《Journal of Structural Chemistry》2021,62(10):1543-1550
Journal of Structural Chemistry - N-(2-methoxy-5-(4,4,5,5-tetramethyl-1,3,2-dioxaborolan-2-yl)pyridin-3-yl)cyclopropanesulfonamide is an organic intermediate with borate and sulfonamide groups,... 相似文献
996.
A. Yan X. Chen R. Zhang M. Liu Z. Hu B. T. Fan 《SAR and QSAR in environmental research》2013,24(3-4):235-244
Abstract Artificial Neural Networks (ANNs) with Extended Delta-Bar-Delta (EDBD) back propagation learning algorithm have been developed to predict the standard enthalpy and entropy of 87 acyclic alkanes. Molecular weight, boiling point and density of the compounds were used as input parameters. The network's architecture and parameters were optimized to give maximum performances. The best network was a 3-6-2 ANN, and the optimum learning epoch was about 1320. The results show that the maximum relative errors of enthalpy and entropy are less than 3%. They reveal that the performances of ANNs for predicting the enthalpy and entropy of alkanes are satisfying. 相似文献
997.
998.
999.
Monosubstituted isopropylidene malonates have been synthesized from Meldrum's acid and carbonyl compounds in the presence of sodium hydrogentelluride as a one pot reaction. 相似文献
1000.
San‐Hu Zhao 《合成通讯》2013,43(23):3045-3053
N‐methylpiperidine, a commercially available mild base, has effectively been utilized as a catalyst in the Morita–Baylis–Hillman reaction. Moderate to excellent yields (34–95%) and significant rate enhancement have been observed. 相似文献