We evaluate the overall sensitivity gains provided by a series of eighteen nitroxide biradicals for dynamic nuclear polarization (DNP) solid-state NMR at 9.4 T and 100 K, including eight new biradicals. We find that in the best performing group the factors contributing to the overall sensitivity gains, namely the DNP enhancement, the build-up time, and the contribution factor, often compete with each other leading to very similar overall sensitivity across a range of biradicals.
View Article and Find Full Text PDFDynamic nuclear polarization (DNP) at cryogenic temperatures has proved to be a valuable technique to enhance the sensitivity of solid-state NMR spectroscopy. Over the years, sample formulations have been optimized for experiments at cryogenic temperatures. At 9.
View Article and Find Full Text PDFRather surprisingly, C-C bond formation through "intermolecular" radical addition to internal ynamides has never been reported. Actually, ynamides are excellent acceptors for "electrophilic" carbon-centered radicals. These processes enable the introduction of functionalized alkyl chains at Cβ, groups that have not yet been introduced via the addition of organometallics.
View Article and Find Full Text PDFA novel series of enediynes possessing pentafluorophenylsulfoxide have been developed. The innovative compounds possess antiproliferative activity against a broad panel of human cancer cells originating from breast, blood, lung, kidney, colon, prostate, pancreas or skin with IC ranging from 0.6 to 3.
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