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112.
首次合成了30种新型O-(1-甲硫基乙叉胺基)磷酰胺酯及磷酸酯类化合物,生物活性测定表明,部分化合物具有一定的杀菌和除草活性,化合物(R1O)2P(O)-ON=C(SCH3)CH3(V)具有一定的杀虫活性. 相似文献
113.
The title compound (C14H10N2O2Cl2) crystallizes in the monoclinic space group P21/a with a=10.042(1) Å, b=10.317(1) Å, c=13.877(2) Å, β=97.36(2)°, V=1425.8(3) Å3, Z=4, Dx=1.44 g.cm‐3. The structure was solved by direct methods and refined by full‐matrix least‐squares method (R = 0.0457). The title molecule consists of 3,4‐dichlorophenylamino and 2‐phenyl‐1,2‐ethanedione‐1‐oxime groups. The intermolecular O‐H…N and N‐H…O hydrogen bonds [O…N 2.760(6) and 3.087(5) Å] are highly effective in forming the polymeric chains. The oxime group has an E configuration. (© 2004 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim) 相似文献
114.
L. Yu. Ukhin V. A. Kharlanov E. V. Solomovich O. V. Shishkin 《Russian Chemical Bulletin》1999,48(5):949-956
Salicylaldehyde aminals react with cyclohexanone upon heating to form tetrahydroxanthene derivatives. The structure of one
of these derivatives,viz., 5,7-dichloro-4a-morpholino-1,2,3,4-tetrahydro-4aH-xanthene, was established by X-ray diffraction analysis. The scheme of the reaction was suggested, which involves cycloaddition
of intermediateo-methylenequinone (from aminal) and enamine (from cyclohexanone). The reactions of salicylaldehyde aminals with enamines that
formed from cyclohexanone can successively afford derivatives of hexahydroxanthene, tetrahydroxanthene, and dihydroxanthene.
Procedures were developed for the synthesis of these compounds.N-Substituted 4a-amino-7-nitro-1,2,3,4-tetrahydro-4aH-xanthenes were also prepared by the reactions of dialkylammonium 2-formyl-4-nitrophenoxides with the above-mentioned enamines.
Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 5, pp. 959–965, May, 1999. 相似文献
115.
116.
建立测定溶剂型涂料中环己酮含量的气相色谱(GC)检测方法。样品在乙酸乙酯中超声提取,以ZB–WAX毛细管柱(30 m×0.25 mm,0.25 μm)为分离色谱柱,加入十四烷作为内标物,氢火焰离子化检测器(FID)检测,内标法定量。结果表明,环己酮的质量浓度在10~250 mg/L范围内呈良好的线性关系,相关系数r=0.999 9。以阴性涂料样品为样品基质,加标平均回收率在92.5%~97.8%之间,测定结果的相对标准偏差在0.87%~1.77%(n=7)之间,方法检出限为13 mg/kg。采用该方法对15种溶剂型涂料样品进行测定,其中11种检出环己酮。该方法能使目标化合物得到有效分离,分析时间短,重复性好,灵敏度高,适用于溶剂型涂料中环己酮含量的快速测定。 相似文献
117.
118.
Three new oxime‐based palladacycles, namely [Pd{C,N‐C6H4{C(Me)?NOH}‐2}(dppm)]ClO4 ( 1 ), [Pd2{C,N‐C6H4{C(Me)?NOH}‐2}2(dppe)2(μ‐dppe)](ClO4)2 ( 2 ) and [Pd{C,N‐C6H4{C(Me)?NOH}‐2}(dppmS2)]ClO4 ( 3 ), were synthesized by the reaction of dinuclear oxime complex [Pd{C,N‐C6H4{C(Me)?NOH}‐2}(μ‐Cl)]2 with different diphosphine ligands (dppm, dppe and dppmS2). The synthesized complexes were characterized using Fourier transform infrared, 31P NMR, 1H NMR and 13C NMR spectroscopic methods and elemental analyses, and their molecular structures were elucidated using X‐ray crystallography. The structure of 2 is worthy of note as it is the first oxime palladacycle where there are both bridging (P–) and chelating (P^P) dppe ligands, giving rise to a dinuclear complex. The palladium atom is in a five‐coordinate, square pyramidal P3NC environment, while in 3 the palladium atom is in a distorted square planar environment, coordinated by the oxime ligand and a chelating (S^S) dppmS2 ligand. These complexes were employed as efficient catalysts for the Suzuki–Miyaura cross‐coupling reaction of several aryl bromides with phenylboronic acid. The in vitro cytotoxicity of the compounds was also evaluated against human tumour cell lines (HT29, A549 and HeLa) using the MTT assay method. The results indicate that the dinuclear complex 2 has greater catalytic and anticancer activity in comparison with the mononuclear complexes 1 and 3 . 相似文献
119.
Livia Corici Daniela Caschera Liliana Cseh Giuseppina De Luca 《Molecular Crystals and Liquid Crystals》2019,684(1):24-36
AbstractThe photochromic compound 2,6-bis(2-hydroxybenzilidene)cyclohexanone (PC) has been dissolved in some selected liquid amphiphiles: dibutyl, tributyl, bis-2-ethylhexyl, tris-2-ethylhexyl phosphate and bis-2-ethylhexyl amine. The aim was to explore its photophysical properties when embedded in the novel chemical environment provided by the amphiphilic solvents. UV-Vis spectra revealed different features depending on the solvent thus highlighting specific solvent-solute interactions and different chemical environments. All the alkylphosphate-based systems were found to be unstable; slow (days) changes in the absorption features due to the slow change in populations of the various species present in solution. Interestingly, the dissolution of PC into bis-2-ethylhexyl amine leads to stable solutions most probably due to the basic character of the solvent stabilising as major specie chalcone forms. Fluorescence spectra suggested the equilibrium between two species with different absorption and fluorescence properties. 相似文献
120.
Stefano Colonna Vincenza PirontiPiero Pasta Francesca Zambianchi 《Tetrahedron letters》2003,44(4):869-871
Cyclohexanone monooxygenase catalyzed the oxidation of tertiary, secondary and hydroxylamines to N-oxides, hydroxylamines and nitrones respectively. 相似文献