The design of inhaled selective phosphatidylinositol 3-kinase delta (PI3Kδ) inhibitors for the treatment of inflammatory lung diseases was pursued. Knowledge-based design of a novel isocoumarin scaffold that was able to adopt a topology ensured the desired PI3Kδ selectivity. Achievement of low nanomolar cellular potencies through hinge binder group optimization, reduction of intrinsic permeability through head group optimization to extend lung retention, and screening of crystalline forms suitable for administration as dry powders culminated in the identification of compound .
View Article and Find Full Text PDFA selective direct arylation of the different Csp2-H bonds of imidazo[2,1-b]thiazole with (hetero) aryl halides can be achieved simply by switching from a palladium catalyst system to the use of stoichiometric amounts of copper. The observed selectivity, also rationalized by DFT calculations, can be explained by a change in the mechanistic pathways between electrophilic palladation and base-promoted C-H metalation.
View Article and Find Full Text PDF