The reduction of stable trivalent lanthanide species (Ln(III)) by the excited states of organic chromophores is the basis of photocatalytic divalent lanthanide-mediated reduction reactions. While indirect evidence of the photochemical formation of the reactive Ln(II) species is abundant, direct spectroscopic evidence of their presence is scarce. Here, nine chromophores with absorptions covering the near UV and visible ranges were systematically investigated in the presence of Ln(III) ions to evaluate their ability to reduce Eu(III) upon excitation with visible light to the catalytically active Eu(II) species.
View Article and Find Full Text PDFCommercially available coumarin 343 in combination with reducible Sm(III) ions catalyzed divalent lanthanide-mediated C═O, C-halogen, P-Cl, and N═N reductions at ambient temperature in aqueous solvent mixtures. The catalyst absorbs visible light efficiently. The active divalent species is formed by photoinduced electron transfer from coumarin 343 to the stable trivalent precursor, and the coumarin could be regenerated by strictly 1 equiv of ascorbic acid.
View Article and Find Full Text PDFCircadian rhythms send messages to regulate the sleep-wake cycle in living beings, which, regulate various biological activities. It is well known that altered sleep-wake cycles affect host metabolism and significantly deregulate the host immunity. The dysregulation of circadian-related genes is critical for various malignancies.
View Article and Find Full Text PDFWith the advancement of internet communication and telemedicine, people are increasingly turning to the web for various healthcare activities. With an ever-increasing number of diseases and symptoms, diagnosing patients becomes challenging. In this work, we build a diagnosis assistant to assist doctors, which identifies diseases based on patient-doctor interaction.
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