Efficient pure blue hyperfluorescence devices utilizing quadrupolar donor-acceptor-donor type of thermally activated delayed fluorescence sensitizers.

The hyperfluorescence (HF) system has drawn great attention in display technology. However, the energy loss mechanism by low reverse intersystem crossing rate (k) and the Dexter energy transfer (DET) channel is still challenging. Here, we demonstrate that this can be mitigated by the quadrupolar donor-acceptor-donor (D-A-D) type of thermally activated delayed fluorescence (TADF) sensitizer materials, DBA-DmICz and DBA-DTMCz.

Manipulating Spectral Width and Emission Wavelength towards Highly Efficient Blue Asymmetric Carbazole Fused Multi-Resonance Emitters.

The novel carbazole-based multiresonance types of thermally activated delayed fluorescence (MR-TADF) emitters of mICz-DABNA and BFCz-DABNA are reported, and their spectroscopic properties are investigated with the inductive effect on the central nitrogen atom for pure and deep blue emission. With the introduction of electron-donating/-withdrawing properties of substituents, emitters exhibited the bathochromic/hypsochromic shifted emission, respectively, compared to simple carbazole-based MR-TADF. Moreover, their spectral bandwidths became narrower.

Synthesis and cytotoxicity of thieno[2,3-b]quinoline-2-carboxamide and cycloalkyl[b]thieno[3,2-e]pyridine-2-carboxamide derivatives.

Seventy nine derivatives of thieno[2,3-b]quinolines, tetrahydrothieno[2,3-b]quinoline, dihydrocyclopenta[b]thieno[3,2-e]pyridine, cyclohepta[b]thieno[3,2-e]pyridine and hexahydrocycloocta[b]thieno[3,2-e]pyridine were either synthesized or obtained commercially and tested for their antiproliferative activity against HCT116, MDA-MB-468 and MDA-MB-231 human cancer cell lines. The most potent eight compounds were active against all cell lines with IC50 values in the 80-250nM range. In general hexahydrocycloocta[b]thieno[3,2-e]pyridines were most active with increasing activity observed as larger cycloalkyl rings were fused to the pyridine ring.