Lignin presents a renewable alternative of fossil feedstock to produce value-added aromaticchemicals. Oxidative cleavage of c-c bonds in lignin is of great importance, but obtaining aromatic monomers in high selectiv...
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Lignin presents a renewable alternative of fossil feedstock to produce value-added aromaticchemicals. Oxidative cleavage of c-c bonds in lignin is of great importance, but obtaining aromatic monomers in high selectivity under mild conditions is challenging. Herein, we report a novel strategy of photoinduced oxidative c-ccleavage of lignin & beta;-O-4 derivatives using photoredox organocatalysts, among which Mes-10-phenyl-Acr+-BF4- exhibited high yields of aromatic aldehydes and phenyl formate. Besides, mixed binary organic solvents were demonstrated to promote bond cleavage and inhibit over-oxidation side reactions. The absorbance, excitation, and interaction with the lignin model of the photocatalyst in different solvents were investigated by UV-Vis, PL, and cV tests. Furthermore, through mechanism studies, a c-centered radical intermediate was captured, providing evidence for the direct c & alpha;- c & beta;bond cleavage mechanism during the reaction. This work presents a new photocatalytic strategy and provides deep insights into the bond cleavage mechanism for lignin valorization.
ceramides, structural components of the cell, are known to play a range of roles in glucose metabolism and apoptosis. c16-ceramide, an abundant molecular species of endogenous ceramide, has not had...
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ceramides, structural components of the cell, are known to play a range of roles in glucose metabolism and apoptosis. c16-ceramide, an abundant molecular species of endogenous ceramide, has not had...
Vitamin c deficiency is common in oncology patients and correlates with a decreased quality of life and a poorer survival rate. Infusion treatments can quickly address these deficiencies, and studies show they bring a...
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Vitamin c deficiency is common in oncology patients and correlates with a decreased quality of life and a poorer survival rate. Infusion treatments can quickly address these deficiencies, and studies show they bring about a significant improvement in quality of life – particularly notable is the relief of fatigue, pain, appetite loss, sleep disturbances, and depression. Moreover, vitamin c treatment leads to less myelosuppression and a clinically significant increase in the lymphocyte count in cases of lymphopenia. Initial clinical trial data also indicates an extension in survival time. This observation is supported by experimental studies that reveal a direct, selective cytotoxic effect on tumors through the formation of hydrogen peroxide, a shift in the epigenetic profile towards tumor suppression, and a decrease in processes relevant to metastasis.
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