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991.
992.
Evans O. Onyango 《合成通讯》2013,43(20):2748-2755
The synthesis of a potential precursor 3 to demethoxyviridin (1b) is described. The centerpiece of this strategy was the conversion of the previously described dibromoolefin 6 to the masked alkyne β-hydroxyaldehyde 5 in a single step. Further elaboration then produced the alkyne oxazole 4, which on thermolysis, followed by in situ tautomerization and silylation, led directly to 3.
Supplementary materials are available for this article. Go to the publisher's online edition of Synthetic Communications® for full experimental and spectral details. 相似文献
993.
《合成通讯》2013,43(24):4583-4590
Abstract α‐Aminonitriles are prepared upon reaction of aryl carboxaldehydes with LiHMDS and acetone cyanohydrin. This new method provides a general route to the synthesis of various substituted α‐amino‐arylacetonitriles in high yield and purity, and avoids the use of the highly toxic cyanide salts. 相似文献
994.
995.
《合成通讯》2013,43(14):1865-1874
Abstract Aerobic oxidation of aralkanes and α,β‐unsaturated carbonyl compounds in the presence of a catalytic amount of N‐hydroxyphthalimide (NHPI) and 2,2′‐Azobis(4‐methoxy‐2,4‐dimethylvaleronitrile) (V‐70) under 1 atmos. of oxygen at 30°C gave α‐hydroperoxyaralkanes and γ‐hydroperoxy‐α,β‐unsaturated carbonyl compounds, respectively. 相似文献
996.
A sequential three-component reaction of aromatic aldehydes with Meldrum's acid and N-methyl indole in the presence of choline chloride/urea ionic liquid as green catalyst has been described. In this one-pot multicomponent reaction, a series of indole-3-propanamide derivatives were synthesized with good to excellent yields. This methodology shows several advantages including fast reaction, easy isolation, operational simplicity that make it a useful and attractive option for the library generation of indole-3-propanamides (5a–l) for drug discovery. [Supplementary materials are available for this article. Go to the publisher's online edition of Synthetic Communications® for the following free supplemental resources: Full experimental and spectral details.] 相似文献
997.
998.
999.
Chi Fang Ting Xiong Jie Hou Jing Wei Gu Mei Hu Sheng 《Journal of Dispersion Science and Technology》2013,34(4):604-610
Amidoxime (AO)/amine co-functionalized polypropylene fiber adsorbents were prepared. The all-polymeric structures were characterized by using Fourier transform infrared spectroscopy (FTIR), optical microscope, contact angle meter and electron spin resonance (ESR) analysis methods, confirming the grafting, modification, and amidoximation stages gravimetrically, spectroscopically, and visually. The properties for the removal of uranyl(VI) from aqueous solutions were investigated. For amidoxime (AO) fiber, high adsorption rate was observed within the first 30 minutes and the plateau value of 40.6% uranium loading (0.0812 mg/g) was reached at around 30 minutes. The adsorption equilibrium for AO/amine fiber was attained within 20 minutes, resulting in the adsorption of 92.6% uranium loading (0.185 mg/g). The percentage of adsorption increases with increasing pH value (2–6), reaches a maximum at pH 6.0 and then remains almost constant for AO/amine fiber, whereas reduces slightly for AO fiber. 相似文献
1000.
Roman M. Balabin 《Journal of Dispersion Science and Technology》2013,34(3):457-463
The dispersed structures of mixtures of five different gasolines with anhydrous ethanol were investigated by the dynamic light scattering (DLS) method. The aim of the work was to find whether these blends are colloid systems. Influence of different parameters was investigated to verify the results of this research. Ethanol‐gasoline blends were found to be colloid systems with the drop size of 20–150 nm. 相似文献