No abstract

Two sets of hydroxyphenyl-benzothiazole based compounds, which exhibited emission colors across the entire visible spectrum for both photoluminescence and electroluminescence, have been designed and synthesized.

We have designed and synthesized a series of 9-anthrylpyrazole derivatives 1,4-bis(3-(9-anthryl)-1-pyrazolylmethyl)benzene (1), 1-(3-(9-anthryl)-1-pyrazolylmethyl)-4-(5-(9-anthryl)-1-pyrazolylmethyl)benzene (2), 1,4-bis(3-(9-anthryl)-1-pyrazolyl)benzene (3), and 1-(3-(9-anthryl)-1-pyrazolyl)-4-(5-(9-anthryl)-1-pyrazolyl)benzene (4). All compounds formed two types of crystals that exhibited anthracene-arrangement-dependent emission colors. For instance, crystal 1a with strong π-overlap between anthracene moieties exhibited an emission maximum at 515 nm, while 1b with no such interchromophore interactions displayed an emission band at 424 nm. The fluorescence quantum yield (ΦF) measurements showed that the blue-emitting crystals have high quantum yields (ΦF = 0.46 for 1b, 0.90 for 2a, 0.91 for 2b, 0.77 for 3b, and 0.51 for 4a), suggesting their potential as blue emitters in optoelectronics.

Crystalline samples of 3(5)-(9-anthryl)pyrazole and its one derivative exhibit interesting piezochromic behaviors with the emission colors differently changing from blue to green and from green to blue, respectively, upon grinding.

The signaling of prostaglandin D (PGD) through G-protein-coupled receptor (GPCR) CRTH2 is a major pathway in type 2 inflammation. Compelling evidence suggests the therapeutic benefits of blocking CRTH2 signaling in many inflammatory disorders. Currently, a number of CRTH2 antagonists are under clinical investigation, and one compound, fevipiprant, has advanced to phase 3 clinical trials for asthma. Here, we present the crystal structures of human CRTH2 with two antagonists, fevipiprant and CAY10471. The structures, together with docking and ligand-binding data, reveal a semi-occluded pocket covered by a well-structured amino terminus and different binding modes of chemically diverse CRTH2 antagonists. Structural analysis suggests a ligand entry port and a binding process that is facilitated by opposite charge attraction for PGD, which differs significantly from the binding pose and binding environment of lysophospholipids and endocannabinoids, revealing a new mechanism for lipid recognition by GPCRs.