Chafuroside B enhanced IL-12 mRNA expression and production in human keratinocytes.

<p>A NHEK were treated with chafuroside B (0.3 and 1 µM). The cells were harvested after 3 h and IL-12 mRNA was quantitated by means of RT-PCR. B NHEK were treated with chafuroside B (0.3 and 1 µM). After 72 h, supernatants were collected and IL-12 was evaluated by means of ELISA. Cha B  =  Chafuroside B. All data are expressed as the mean ± sd (<i>n</i> = 3 or 4). *<i>P</i><0.05 compared with the control.</p

Chafuroside B attenuated DNA damage, cell damage, and apoptosis in UVB-exposed human keratinocytes.

<p>A Chemical structure of chafuroside B. B NHEK were irradiated with UVB (20 mJ/cm²), and then treated with chafuroside B (0.3 and 1 µM). Alamar blue assay was used to evaluate cell viability at 48 h after treatment. C, D NHEK were irradiated with UVB (20 mJ/cm²), and then treated with chafuroside B (1 µM). After 6 h, apoptotic cells were detected with CellEvent Caspase-3/7 Green Detection Reagent, which produces bright green fluorescence. Nuclei were stained using Hoechst 33342, exhibiting blue fluorescence. Numbers below the panel indicate percent of caspase-3/7-active cells detected in each population (100 cells, at least, were counted in each of the plates). E NHEK were irradiated with UVB (20 mJ/cm²), and then treated with chafuroside B (1 µM). After 24 h, CPD in genomic DNA was detected by an immunofluorescence method using FITC-labeled CPD specific antibodies. Cha B  =  Chafuroside B. All data are expressed as the mean ± sd (<i>n</i> = 3 or 4). *<i>P</i><0.05, **<i>P</i><0.01 and ***<i>P</i><0.001 compared with UVB (+).</p

Chafuroside B decreased the mRNA expression of RANKL induced by UVB radiation in human keratinocytes.

<p>NHEK were irradiated with UVB (20 mJ/cm²), and then treated with chafuroside B (0.3 and 1 µM). The cells were harvested after 24 h and RANKL mRNA was evaluated by means of RT-PCR. Cha B  =  Chafuroside B. All data are expressed as the mean ± sd (<i>n</i> = 3 or 4). *<i>P</i><0.05 compared with UVB (+).</p

Environmentally Friendly Mechanochemical Syntheses and Conversions of Highly Luminescent Cu(I) Dinuclear Complexes

Luminescent dinuclear Cu­(I) complexes, [Cu₂X₂(dpypp)₂] [<b>Cu-X</b>; X = Cl, Br, I; dpypp = 2,2′-(phenylphosphinediyl)­dipyridine], were successfully synthesized by a solvent-assisted mechanochemical method. A trace amount of the assisting solvent plays a key role in the mechanochemical synthesis; only two solvents possessing the nitrile group, CH₃CN and PhCN, were effective for promoting the formation of dinuclear <b>Cu-X</b>. X-ray analysis revealed that the dinuclear structure with no Cu···Cu interactions, bridged by two dpypp ligands, was commonly formed in all <b>Cu-X</b> species. These complexes exhibited bright green emission in the solid state at room temperature (Φ = 0.23, 0.50, and 0.74; λ_em = 528, 518, and 530 nm for <b>Cu-Cl</b>, <b>Cu-Br</b>, and <b>Cu-I</b>, respectively). Emission decay measurement and TD-DFT calculation suggested that the luminescence of <b>Cu-X</b> could be assigned to phosphorescence from the triplet metal-to-ligand charge-transfer (³MLCT) excited state, effectively mixed with the halide-to-ligand charge-transfer (³XLCT) excited state, at 77 K. The source of emission changed to thermally activated delayed fluorescence (TADF) with the same electronic transition nature at room temperature. In addition, the CH₃CN-bound analogue, [Cu₂(CH₃CN)₂­(dpypp)₂]­(BF₄)₂, was successfully mechanochemically converted to <b>Cu-X</b> by grinding with solid KX in the presence of a trace amount of assisting water

Chafuroside B decreased the UVB-induced production of TNF-α, PGE₂, and IL-10 in human keratinocytes.

<p>NHEK were irradiated with UVB (20 mJ/cm²), and then treated with chafuroside B (0.3 and 1 µM). After 48 h, supernatants were collected and the levels of TNF-α, PGE₂, and IL-10 were evaluated by ELISA. (A) TNF-α. (B) PGE₂. (C) IL-10. Cha B  =  Chafuroside B. All data are expressed as the mean ± sd (<i>n</i> = 4). *<i>P</i><0.05, **<i>P</i><0.01 and ***<i>P</i><0.001 compared with UVB (+).</p

Emission Tuning of Luminescent Copper(I) Complexes by Vapor-Induced Ligand Exchange Reactions

We have synthesized two luminescent mononuclear Cu­(I) complexes, [Cu­(PPh₂Tol)­(THF)­(4Mepy)₂]­(BF₄) (<b>1</b>) and [Cu­(PPh₂Tol)­(4Mepy)₃]­(BF₄) (<b>2</b>) (PPh₂Tol = diphenyl­(<i>o</i>-tolyl)­phosphine, 4Mepy = 4-methylpyridine, THF = tetrahydrofuran), and investigated their crystal structures, luminescence properties, and vapor-induced ligand exchange reactions in the solid state. Both coordination complexes are tetrahedral, but one of the three 4Mepy ligands of complex <b>2</b> is replaced by a THF solvent molecule in complex <b>1</b>. In contrast to the very weak blue emission of the THF-bound complex <b>1</b> (wavelength of emission maximum (λ_em) = 457 nm, emission quantum yield (Φ_em) = 0.02) in the solid state at room temperature, a very bright blue-green emission was observed for <b>2</b> (λ_em = 484 nm, Φ_em = 0.63), suggesting a contribution of the THF ligand to nonradiative deactivation. Time-dependent density functional theory calculations and emission lifetime measurements suggest that the room-temperature emissions of the complexes are due to thermally activated delayed fluorescence from the metal-to-ligand charge transfer excited state. Interestingly, by exposing the solid sample of THF-bound <b>1</b> to 4Mepy vapor, the emission intensity drastically increased and the emission color changed from blue to blue-green. Powder X-ray diffraction measurements revealed that the emission change of <b>1</b> is due to the vapor-induced ligand exchange of THF for 4Mepy, forming the strongly emissive complex <b>2</b>. Further emission tuning was achieved by exposing <b>1</b> to pyrimidine or pyrazine vapors, forming green (λ_em = 510 nm) or orange (λ_em = 618 nm) emissive complexes, respectively. These results suggest that the vapor-induced ligand exchange is a promising method to control the emission color of luminescent Cu­(I) complexes

Core-Structure-Dependent Luminescence of Thiolato-Bridged Copper(I) Cluster Complexes

Thiolato-bridged dinuclear, tetranuclear, and hexanuclear Cu­(I) complexes [Cu₂(P^∧S)₂(PPh₃)₂], [Cu₄(P^∧S)₄(CH₃CN)₂], and [Cu₆(P^∧S)₆] (abbreviated as <b>Cu</b>_<b>2</b>, <b>Cu</b>_<b>4</b>, and <b>Cu</b>_<b>6</b>, respectively, P^∧S = 2-(diphenylphosphino)­benzenethiolate, PPh₃ = triphenylphosphine) were synthesized and characterized by elemental analyses and single-crystal X-ray diffraction measurements. These complexes had {Cu₂S₂}, {Cu₄S₄}, and {Cu₆S₆} cluster cores and exhibited strong luminescence at room temperature in solid states. Different luminescence properties were observed depending on the core structure. <b>Cu</b>_<b>2</b>, <b>Cu</b>_<b>4</b>, and <b>Cu</b>_<b>6</b> exhibited blue-green (λ_max = 482 nm, Φ_em = 0.52), green (λ_max = 526 nm, Φ_em = 0.19), and yellow (λ_max = 553 nm, Φ_em = 0.49) luminescence, respectively, at 298 K in the solid state; among them, only <b>Cu</b>_<b>6</b> showed luminescence thermochromism. Different radiative rate constants at room temperature and 78 K derived from the emission lifetimes and quantum yields indicate that the luminescence from <b>Cu</b>_<b>2</b> and <b>Cu</b>_<b>4</b> at room temperature originated from thermally activated delayed fluorescence (TADF), whereas the luminescence at low temperatures was attributed to the phosphorescence. The temperature dependence of the emission lifetimes was successfully analyzed by the singlet–triplet two-state model with an energy difference (Δ<i>E</i>_S₁‑T₁) of 547 and 775 cm^–1 for <b>Cu</b>_<b>2</b> and <b>Cu</b>_<b>4</b>, respectively. Based on the time-dependent density-functional theory calculations, the origin of the luminescence for <b>Cu</b>_<b>2</b> and <b>Cu</b>_<b>4</b> was attributed to the charge transfer from the cluster core to the ligand. Moreover, the small values of Δ<i>E</i>_S₁‑T₁ for <b>Cu</b>_<b>2</b> and <b>Cu</b>_<b>4</b> were supported by the excited state calculations. On the other hand, the emission origin of <b>Cu</b>_<b>6</b> was attributed to the phosphorescence from the triplet cluster-centered (³CC) excited state in which the electron is located on a bonding in-phase orbital constructed from the 4s/4p orbitals of the Cu atoms because only <b>Cu</b>_<b>6</b> contains trigonal-planar Cu­(I) ions in the cluster