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Some molecular probes that can detect reactive oxygen species (ROS) with deep-red fluorescence (FL) were designed and synthesized through modification of di(acenaphtho)BODIPY (DAB), which has a sharp absorption band around 680 nm. In order to detect ROS, anthracene or maleimide moiety was substituted at α - or meso -position of DAB, which would work as an FL switch. The obtained DAB having an anthracene moiety at the α -position showed suppressed FL and potential usefulness as a probe for detecting 1O 2 and the 2-cyano-2-propyl radical (•CP) in acetonitrile. On the other hand, although DAB having an N -phenylmaleimide moiety at the meso -position showed suppressed FL, it could detect neither the hydroxyl radical nor •CP. DAB having a hydroxylamine moiety, which was accidently obtained as an intermediate in synthesis, worked as a •CP probe in ethanol and in acetonitrile. These DAB probes are promising tools for studying objects of interest related to ROS such as behaviors caused by oxidative stresses, antioxidation processes in living bodies, medicinal substances, food factors, and so on. [Display omitted] • Modified di(acenaphtho)BODIPYs as ROS detection probes having deep red fluorescence. • α -Anthracenyl substituent acts as a switch for fluorescence by trapping singlet oxygen. • meso -Phenyl-hydroxylamine moiety works for detection of free radicals. [ABSTRACT FROM AUTHOR]

c-Src tyrosine kinase plays roles in a wide range of signaling events and its increased activity is frequently observed in a variety of epithelial and non-epithelial cancers. v-Src, an oncogene first identified in the Rous sarcoma virus, is an oncogenic version of c-Src and has constitutively active tyrosine kinase activity. We previously showed that v-Src induces Aurora B delocalization, resulting in cytokinesis failure and binucleated cell formation. In the present study, we explored the mechanism underlying v-Src-induced Aurora B delocalization. Treatment with the Eg5 inhibitor (+)-S-trityl-L-cysteine (STLC) arrested cells in a prometaphase-like state with a monopolar spindle; upon further inhibition of cyclin-dependent kinase (CDK1) by RO-3306, cells underwent monopolar cytokinesis with bleb-like protrusions. Aurora B was localized to the protruding furrow region or the polarized plasma membrane 30 min after RO-3306 addition, whereas inducible v-Src expression caused Aurora B delocalization in cells undergoing monopolar cytokinesis. Delocalization was similarly observed in monopolar cytokinesis induced by inhibiting Mps1, instead of CDK1, in the STLC-arrested mitotic cells. Importantly, western blotting analysis and in vitro kinase assay revealed that v-Src decreased the levels of Aurora B autophosphorylation and its kinase activity. Furthermore, like v-Src, treatment with the Aurora B inhibitor ZM447439 also caused Aurora B delocalization at concentrations that partially inhibited Aurora B autophosphorylation. Given that phosphorylation of Aurora B by v-Src was not observed, these results suggest that v-Src causes Aurora B delocalization by indirectly suppressing Aurora B kinase activity. • CDK1 inhibition of STLC-arrested cells induces monopolar cytokinesis. • Aurora B localization can be analyzed in monopolar cytokinesis cells. • MPS1 inhibition instead of CDK1 inhibition causes monopolar cytokinesis in STLC-arrested cells. • v-Src reduces Aurora B kinase activity, causing the Aurora B delocalization. • LATS kinases inhibition causes the Aurora B delocalization. [ABSTRACT FROM AUTHOR]

[Display omitted] • Solvent effects on the S 1 ← S 0 absorption spectra are investigated for aniline. • MD simulations and TD-DFT calculations reproduce the experimental spectra. • A solvent molecule bound to the nitrogen atom of aniline causes a blue shift. • Methanol is bound to the nitrogen atom less frequently than water in solution. • The absorption band in methanol is thus less-blue shifted than the band in water. Solvent effects on the absorption spectra of aniline (C 6 H 5 NH 2) are investigated. DFT and TD-DFT calculations for 1:1 aniline–water and aniline–methanol complexes predict that an N-bound isomer with an OH···N bond is the global minimum in the S 0 state, while an H-bound isomer with an NH···O bond becomes lower in the S 1 state. The N-bound and H-bound solvents cause blue and red shifts, respectively. MD simulations are used to allocate solvent molecules around aniline for constructing model structures with a complete solvation shell. TD-DFT calculations for the model structures are successful in reproducing the experimental observation that the absorption band in methanol is less blue-shifted than that in the water. At least one water molecule is incessantly bound to the nitrogen atom and causes the significant blue shift. In contrast, methanol molecules are less frequently bound to the nitrogen atom and therefore the blue-shifting effect is less significant. [ABSTRACT FROM AUTHOR]