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ZhiZhouYUE YuanChaoLI 《中国化学快报》2005,16(2):171-174
Highly efficient synthesis of the entitled compound was achieved from a readily available myo-inositol derivative. The key step involved a desymmetrization with ( )-camphor dimethyl ketal to give two diastereomers. The two diastereomers could be used to synthesize the same compound by changing the orders to introduce the protective groups. 相似文献
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Dz. Sile V. A. Slavinska G. Rozental J. Popelis Yu. Balodis E. Lukevics 《Chemistry of Heterocyclic Compounds》2002,38(3):287-291
We have developed a method for the synthesis of ethyl 4-(3-pyridyl)- and 4-(4-pyridyl)-2-oxobutenoates by condensation of 3-pyridinecarbaldehyde and 4-pyridinecarbaldehyde monohydrate respectively with ethyl pyruvate, esterifiction of the target acids, and hydrolysis of the corresponding ethyl ester ketals in the presence of FeCl3·6H2O. 相似文献
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Herein, we describe a concise assembly of central 6,8-dioxabicyclo[3,2,1]octane core of didemniserinolipid by employing a Pd-mediated alkynediol cycloisomerization and a formal total synthesis of didemniserinolipid B. 相似文献
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4,5-Diaryl-Δ4-imidazolin-2-ones undergo conversion to 2,2-dialkoxy-4,5-diaryl-Δ4-imidazolines by a characteristic solvent interaction of the carbonyl group on irradiation in alcoholic solvents. The photochemical
oxidative cyclization of the stilbene system in these compounds to the corresponding phenanthrene derivatives does not occur
under the usual conditions. Acidic conditions hinder the ketal formation of the carbonyl group and favour the oxidative dehydrocyclization
reaction to the phenanthrene derivatives. These reactions have been found to be general to the 4,5-diaryl-Δ4-imidazolin-2-ones and plausible mechanistic pathways have been suggested for the two different selective reactions. 相似文献
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Novel caged intramolecular ketals of β‐C‐glycosidic ketones were prepared from pyranoses. The structures of the new compounds were elucidated by NMR and HRMS spectral analysis. Preliminary studies revealed that the intramolecular ketal could be used to protect 3‐ and 6‐hydroxyl groups of β‐C‐glycosidic ketones. 相似文献
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