Aza-annulation of enamines derived from β-ketoesters with maleic and itaconic anhydrides proceeds with excellent diastereoselectivity to provide functionalized γ- and δ-lactams. Further hydrolysis of the aza-annulation products resulted in dicarboxylic acids that underwent spontaneous decarboxylation under ambient conditions. The decarboxylation of β-γ unsaturated carboxylic acids with an electron-rich enamide C═C bond proceeds with the migration of the C═C bond and serves as a practical synthetic entry into 3-pyrrolin-2-ones and 1,2,3,4-tetrahydropyridin-2-ones.
View Article and Find Full Text PDFSimple and scalable electrochemical oxidation of the electron-rich benzene ring followed by intramolecular capture of reactive cation-radical intermediates opens access to spirocyclic morpholines and tetrahydrofurans. The obtained molecules can be readily modified to value-added building blocks.
View Article and Find Full Text PDFThis review surveys Infrared, Raman/SERS and Brillouin spectroscopies for medical diagnostics and detection of biomarkers in biofluids, that include urine, blood, saliva and other biofluids. These optical sensing techniques are non-contact, noninvasive and relatively rapid, accurate, label-free and affordable. However, those techniques still have to overcome some challenges to be widely adopted in routine clinical diagnostics.
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