A procedure has been developed for the synthesis of Pro-Drone homo analogs from the ozonolysis products of 1,5-dimethylcycloocta-1,5-diene
and 1,5-dimethylcyclooctene. 相似文献
Chemistry of Heterocyclic Compounds - An efficient one-pot method was developed for the preparation of quaternary pyridinium salts and tetrahydropyridine derivatives of fusidane triterpenoids,... 相似文献
Russian Journal of Organic Chemistry - The reduction of 4-oximes derived from 1β-hydroxy-, 1β,13-epoxy-, and 1,1-(ethylenedioxy)dihydroquinopimaric acid methyl esters, as well... 相似文献
Recent research revealed that tissue spray mass spectrometry enables rapid molecular profiling of biological tissues, which is of great importance for the search of disease biomarkers as well as for online surgery control. However, the payback for the high speed of analysis in tissue spray analysis is the generally lower chemical sensitivity compared with the traditional approach based on the offline chemical extraction and electrospray ionization mass spectrometry detection. In this study, high resolution mass spectrometry analysis of endometrium tissues of different localizations obtained using direct tissue spray mass spectrometry in positive ion mode is compared with the results of electrospray ionization analysis of lipid extracts. Identified features in both cases belong to three lipid classes: phosphatidylcholines, phosphoethanolamines, and sphingomyelins. Lipids coverage is validated by hydrophilic interaction liquid chromatography with mass spectrometry of lipid extracts. Multivariate analysis of data from both methods reveals satisfactory differentiation of eutopic and ectopic endometrium tissues. Overall, our results indicate that the chemical information provided by tissue spray ionization is sufficient to allow differentiation of endometrial tissues by localization with similar reliability but higher speed than in the traditional approach relying on offline extraction.
Cyclopropanation of methyl (2E)-3-[(1R,6S)-7,7-dimethyl-2-oxo-3-oxabicyclo[4.1.0]hept-4-en-4-yl]prop-2-enoate with dichlorocarbene occurred at the endocyclic double bond, while its reaction with diazomethane in the presence of Pd(acac)2 involved the exocyclic double bond. The resulting lactones reacted with sodium methoxide in methanol via opening of one cyclopropane fragment. 相似文献
3,11-Dihydroxy and 3,11-dioxo triterpenoids of the fusidane series reacted with acrylonitrile in 1,4-dioxane in the presence of alkali and phase-transfer catalyst to give mono- and bis(2-cyanoethoxy) and 2-cyanoethyl derivatives. The reaction with 3,11-dioxo analog afforded 2,2-disubstituted derivative as a result of addition of two cyanoethyl groups to the α-position with respect to the C3=O carbonyl group. The isolated compounds were screened for antibacterial and antifungal activities.
Amides of betulonic and oleanonic acids with diethylenetriamine, triethylenetetramine, and spermidine were synthesized. Antitumor
activity in vitro was not found for the conjugate of betulonic acid with diethylenetriamine. 相似文献