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81.
Da Yeon Park 《Tetrahedron letters》2007,48(9):1633-1636
Poly-substituted nitrobenzenes were synthesized from Baylis-Hillman adducts via the [3+3] annulation strategy as the key step. 1,3-Dinitroalkanes served as the 1,3-dinucleophilic component and the Baylis-Hillman acetates as a 1,3-dielectrophilic part. 相似文献
82.
Mi Jung Lee 《Tetrahedron letters》2006,47(8):1355-1358
A new and regioselective [4+2] benzannulation protocol toward polysubstituted benzenes was developed. Nitroalkane derivative, which was prepared from Baylis-Hillman adduct, served as the four-carbon unit and Michael acceptor as a two-carbon unit. 相似文献
83.
Da Yeon Park 《Tetrahedron letters》2006,47(37):6641-6645
Polysubstituted benzene derivatives were synthesized starting from the Baylis-Hillman adducts via the sequential introduction of primary nitroalkane at the primary position, Michael addition to β-branched Michael acceptor, aldol condensation, elimination of nitrous acid, and the final aromatization process. 相似文献
84.
《Journal of Coordination Chemistry》2012,65(15):2631-2638
The adducts of bis(O,O′-dialkylmonoselenophosphato)cobalt(II) complexes, Co{O(Se)P(OR)2}2(L)4 (where R?=?n-Pr, i-Pr; L?=?C5H5N, NC5H4Me-2, NC5H4Me-3), were synthesized by in situ reactions of CoCl2?·?6H2O, Lewis base, and NaO(Se)P(OR)2. The single crystal structure of Co{O(Se)P(OiPr)2}2(C5H5N)4 shows distorted octahedral geometry around cobalt(II) and monoselenophosphates are trans. The CoN4 forms a square plane. These bis(O,O′-dialkylmonoselenophosphato)cobalt(II) adducts were characterized by elemental analyses, spectroscopic techniques (UV-Vis, infrared, 1H and 31P), and magnetic moment measurements. 相似文献
85.
Kinetics and mechanism of nitration of aromatic compounds using trichloroisocyanuric acid (TCCA)/NaNO2, TCCA-N,N-dimethyl formamide (TCCA-DMF)/NaNO2, and TCCA-N,N-dimethyl acetamide (TCCA-DMA)/NaNO2 under acid-free and Vilsmeier-Haack conditions. Reactions followed second-order kinetics with a first-order dependence on [Phenol] and [Nitrating agent] ([TCCA], [(TCCA-DMF)], or [(TCCA-DMA)] >> [NaNO2]). Reaction rates accelerated with the introduction of electron-donating groups and retarded with electron-withdrawing groups, but did not fit well into the Hammett's theory of linear free energy relationship or its modified forms like Brown-Okamoto or Yukawa-Tsuno equations. Rate data were analyzed by Charton's multiple linear regression analysis. Isokinetic temperature (β) values, obtained from Exner's theory for different protocols, are 403.7 K (TCCA-NaNO2), 365.8 K (TCCA-DMF)/NaNO2, and 358 K (TCCA-DMA)/NaNO2. These values are far above the experimental temperature range (303-323 K), indicating that the enthalpy factors are probably more important in controlling the reaction. 相似文献
86.
Jia Yang Xingang Li Wenjun Li Xin Xi Qian Du Feng Pan Songqing Liu 《Biomedical chromatography : BMC》2020,34(8):e4857
Because of its unpredictable side effects and efficacy, the anticancer drug docetaxel (DTX) requires improved characterisation of its pharmacokinetic profiles through population pharmacokinetic studies. A sensitive and rugged LC–MS/MS method for the detection of DTX in human plasma was developed and optimised using paclitaxel as an internal standard (IS). The plasma samples underwent rapid extraction using hybrid solid-phase extraction-protein precipitation. The analyte and IS were separated with an isocratic system on a Zorbax Eclipse Plus C18 column using water containing 0.05% acetic acid along with 20 μM of sodium acetate and methanol (30/70, v/v) as the mobile phase. Quantification was performed using a triple quadrupole mass spectrometer through multiple reaction monitoring in positive mode, using the m/z 830.3 → 548.8 and m/z 876.3 → 307.7 transitions for DTX and paclitaxel, respectively. The range of the calibration curve was 1–500 ng/mL for DTX, and the linear correlation coefficient was >0.99. The accuracies ranged from −4.6 to 4.2%, and the precision was no higher than 7.0% for the analytes. No significant matrix effect was observed. Both DTX and the IS showed considerable recovery. This method was finally applied to the establishment of a population pharmacokinetic model to optimise the clinical use of DTX. 相似文献
87.
Gao Pei‐Sen Zhang Jin‐Lei Li Ning Zheng Zhan Jiang Yuan Yang Gao Zi‐Wei Zhang Weiqiang Xu Li‐Wen 《应用有机金属化学》2018,32(3)
Catalytic allylic γ‐substitution with Morita‐Baylis‐Hillman (MBH) adducts for creating a new family of unsymmetrical dicarbonyl compounds was presented in this work, in which a variety of allylated amide products were achieved in good yields and high regioselectivity with excellent linear‐to‐branched ratios. Especially, it was found that the Pd/HZNU‐Phos complex exhibited remarkably high activity (with a TON up to 16800) in this transformation between dicarbonyl amides and MBH adducts. In addition, the possibly multisite interaction between multifunctional Pd/HZNU‐Phos catalyst system and substrates might responsible for its exceptionally high efficiency in this reaction. 相似文献
88.
Jyoti M. Madar Samundeeswari L. Shastri Megharaja Holiyachi Nirmala Naik Rashmi Kulkarni 《合成通讯》2018,48(4):375-386
Pursuing our recent interest regarding antimicrobial and anti-inflammatory activities of coumarin derivatives, we have synthesized a series of coumarin-linked pyridopyrimidinones by using Baylis Hillman adduct in aqueous condition with high purity. Pyrido[1,2-a]pyrimidin-2-ones are important class of heterocyclic compounds because of their use in medicinal and agro chemistry as active agents. All these newly synthesized compounds were evaluated for their antimicrobial and anti-inflammatory activity. Coumarin pyridopyrimidinones showed excellent anti-inflammatory activity against both MMP-2 and MMP-9 gelatinase zymography, whereas considerable good activity against Gram-positive and Gram-negative bacterial strains; however, antifungal activity observed in these series is more or less inactive. The active compounds of these series would be promising structural templates for the development of novel and more efficient anti-inflammatory agent. 相似文献
89.
本文在室温下对C60分别在吡啶、甲苯和乙腈中的荧光了研究,实验表明:C60在吡啶中的荧光由以440nm、570nm和700nm为中心的三个荧光带组成;C60在甲苯中的荧光由以430nm和700nm为中心的两个荧光带组成;C60在乙腈中的荧光由以570nm和700nm为中心的两个荧光带组成。经比较分析发现C60-有机溶剂体系700nm区域的荧光带的发射与溶剂的种类无关,而440nm和570nm区域的荧光带及其精细结构可以反映C60与溶剂分子的特殊相互作用。进一步提出C60-吡啶体系以570nm为中心的荧光带是由吡啶分子通过含孤对电子的N与C60形成的电荷转移络合物发出的。 相似文献
90.
Rodrigo O.M.A. de Souza Vera L.P. Pereira Mario L.A. A. Vasconcellos 《Tetrahedron letters》2008,49(41):5902-5905
We have found that water and organic solvents mixed at different proportions can give good to excellent yields and short reaction times for the Morita-Baylis-Hillman reaction. The present Letter details our findings in the Morita-Baylis-Hillman reaction between several aromatic aldehydes and methyl acrylate or acrylonitrile. The selection of the catalyst was also evaluated and DABCO affored the best results when compared to DBU, DMAP, HMT, Imidazole and Triethylamine. 相似文献