Fluorinated Organic Molecules for Medicinal Applications

The significant applications of fluorinated molecules in the pharmaceutical, agrochemical, and material sciences make them attractive synthetic targets. Difluoromethylation methods are of exceptional value and a limited number of techniques are available to perform that transformation. The primary method for introducing CF2 groups is through the use of difluoroenolates. Difluoroenolates can be generated from α-keto pentafluoro gem -diols under mild conditions. The process involves the cleavage of carbon-carbon bond and the release of trifluoroacetate. The release of trifluoroacetate is a versatile method to generate fluorinated molecules. We explored the utility of this method in generating various fluorinated moieties including α,α-difluoroketones, α-deutero-α,α-difluoroketones, α,α-difluoromethyl sulfones, ?-deutero-α,α-difluoromethyl sulfones, monofluoro α-hydroxy ketones and α,α-difluorohalohydrins. We also endeavored to design and synthesize fluorinated molecules for biological applications. Our efforts were aimed at the use of a novel fluorinated β-hydroxy ketone scaffold developed in our lab to develop new agonists of the GABAB receptor. The value of GABAB agonists as muscle relaxants is well established, and interest in these agonists has been rekindled due to reports of new applications in managing drug and alcohol tolerance. We have developed several new analogues, characterized new structure-activity relationships of the fluorinated ?-hydroxy ketone scaffold, and identified more active agents. We are also interested in using fluorine as a tag to track anti-body drug conjugates (ADCs). The chemistry of ADC linkers has attracted a lot of interest recently. The cleavage of the linker is essential for the function of ADCs and in addition to this traditional role, linkers can provide a handle for tagging ADCs. The incorporation of fluorine into linkers minimally affects the sterics of the linker owing to the small size of fluorine atom while at the same time provides a tractable tag. A fluorinated ADC linker has been designed and its synthesis was explored

Synthesis of kinase inhibitors containing a pentafluorosulfanyl moiety

A series of 3-methylidene-1H-indol-2(3H)-ones substituted with a 5- or 6- pentafluorosulfanyl group has been synthesized by a Knoevenagel condensation reaction of SF5-substituted oxindoles with a range of aldehydes. The resulting products were characterized by x-ray crystallography studies and were tested for biological activity versus a panel of cell lines and protein kinases. Some exhibited single digit nM activity