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Palladium-catalyzed coupling reactions on functionalized 2-trifluoromethyl-4-chromenone scaffolds. Synthesis of highly functionalized trifluoromethyl-heterocycles.

ABSTRACT: The chromenone core is a ubiquitous group in biologically-active natural products and has been extensively used in organic synthesis. Fluorine derived compounds, including those with a trifluoromethyl group (-CF₃), have shown enhanced biological activities in numerous pharmaceuticals compared with their non-fluorinated analogs. We have found that 2-trifluoromethyl chromenones can be readily functionalized in the 8- and 7-positions, providing chromenones cores of high structural complexity which are excellent precursors for numerous trifluoromethyl-heterocycles.

SUBMITTER: Izquierdo J

PROVIDER: S-EPMC6605783 | biostudies-literature | 2019 Mar

REPOSITORIES: biostudies-literature

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Variation in preventive service use among the insured and uninsured: does length of time without coverage matter?

Bednarek Heather L HL Schone Barbara Steinberg BS

Journal of health care for the poor and underserved 20030801 3

Lacking health insurance has consequences for the ways in which individuals seek care. In this research, the authors use data from the first panel (1996) of the Medical Expenditure Panel Survey to assess the relationship between preventive services and the length of time with insurance during a 12-month period. Regression analyses show that individuals with continuous coverage during the entire period have dramatically higher rates of preventive service use than individuals who lack coverage for ...[more]

PMID: 12955919

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