53 research outputs found
A novel phenolic acid from the fruits of <i>Rosa soulieana</i>
<div><p>From the <i>n</i>-BuOH-soluble fraction of a MeOH extract of the fruits of <i>Rosa soulieana</i>, one new phenolic glucoside (<b>1</b>) was isolated along with five known compounds, comprising two lignin glycosides, two flavonoid glycosides and a phenolic glycoside. The chemical structure of the new compound was elucidated by extensive spectroscopic analyses, including ESI-MS, UV, IR, <sup>1</sup>H and <sup>13</sup>C NMR, DEPT and 2D NMR (HSQC and HMBC). All the isolated compounds were evaluated for their antioxidant activity by using ABTS (2,2′-azino-bis(3-ethylbenzoline-6-sulfonic acid)) assay. Among these compounds, <b>1</b>, <b>3</b> and <b>6</b> exhibited strong scavenging activity in ABTS<sup>√+</sup>(SC<sub>50</sub> = 102.10, 193.85, 65.38 μmol/L, respectively) compared with the positive control l-ascorbic acid (<i>Vc</i>) (SC<sub>50</sub> = 117.16 μmol/L).</p></div
Light Scattering in Nanoparticle Doped Transparent Polyimide Substrates
Here we demonstrate
a simple and effective method of fabricating polymeric scattering
substrate for flexible organic light-emitting diodes (OLEDs) that
require no costly patterning, etching, or molding processes, aspects
that are desirable for the commercialization of large-scale lighting
panels. Systematic study of the influences of relative index of refraction,
particle size, and doping concentration on transmittance and haze
of transparent colorless polyimide (cPI) films was carried out. It
was found that the reduction of transmittance and haze of the doped
films decreases along with the decrease of the difference of refractive
index between the particles and polymer matrix, and it could be compensated
by the increase of particle size or doping concentration
Amphiphilic Diblock Fullerene Derivatives as Cathode Interfacial Layers for Organic Solar Cells
A new amphiphilic
diblock fullerene derivative [6,6]-phenyl-C<sub>61</sub>-butyricacid-4-(9,9,9′,9′-tetrakisÂ(3-bromopropyl)-9<i>H</i>,9′<i>H</i>-[2,2′-bifluoren]-7-yl)Âphenol-(<i>N</i>,<i>N</i>,<i>N</i>-trimethylpropan-1-aminium)
bromide (C<sub>60</sub>-4TPB) was synthesized and applied in organic
solar cells. Solvent annealing by toluene could obviously induce the
self-assembly of the C<sub>60</sub>-4TPB layer, which can be tested
by the measurements of the water contact angle. After the treatment
with toluene, a vertical-like arrangement in the ultrathin layer of
the C<sub>60</sub>-4TPB molecule will be formed between electron-collecting
zinc oxide (ZnO) layers and the active layer (blend system of PTB7:PC<sub>71</sub>BM), leading to the improvement of the interfacial compatibility
between the active layer and the ZnO layer. On the top surface of
the C<sub>60</sub>-4TPB layer, the C<sub>60</sub> molecules can be
expected to induce the enrichment of PC<sub>71</sub>BM and block the
hole, resulting in further increase in the open-circuit voltage (<i>V</i><sub>OC</sub>) and fill factor (FF). After spin-coating
the C<sub>60</sub>-4TPB solutions onto the ZnO layer with a concentration
of 0.5 mg/mL in dimethyl sulfoxide, obviously improved performances
were obtained with a power conversion efficiency of 8.07%, which can
be attributed to the optimized interface morphology between hydrophilic
ZnO and hydrophobic PTB7:PC<sub>71</sub>BM
Two new polyacetylene glycosides from the roots of <i>Codonopsis tangshen</i> Oliv.
<p>Two new polyacetylene glycosides, tangshenyne A (<b>1</b>) and tangshenyne B (<b>2</b>), along with six known polyacetylenes were isolated from an 85% MeOH extract of the roots of <i>Codonopsis tangshen</i> Oliv. The chemical structures of the new compounds were determined on the basis of extensive spectroscopic analyses, including UV, IR, 1D and 2D NMR (<sup>1</sup>H–<sup>1</sup>H COSY, HSQC and HMBC) and HR-ESI-MS.</p
1H-NMR spectral data °f the newly isolated compounds 1, 2, and 3 (600 MHz in DMSO-d6, δ in ppm, J in Hz).
<p>1H-NMR spectral data °f the newly isolated compounds 1, 2, and 3 (600 MHz in DMSO-d6, δ in ppm, J in Hz).</p
Radical-scavenging activity of the compounds isolated from BPL.
a<p>The SC<sub>50</sub> value of each compound was defined as the concentration (μM) that caused 50% scavenging capability of ABTS and DPPH.</p>b<p>Ascorbic acid was used as a positive control.</p
1H-NMR spectral data of the newly isolated compounds 4 and 5 (600 MHz in DMSO-d6, δ in ppm, J in Hz).
<p>1H-NMR spectral data of the newly isolated compounds 4 and 5 (600 MHz in DMSO-d6, δ in ppm, J in Hz).</p
Cytotoxic Phorbol Esters of <i>Croton tiglium</i>
Chemical investigation of the seeds
of <i>Croton tiglium</i> afforded eight new phorbol diesters
(three phorbol diesters, <b>1</b>–<b>3</b>, and
five 4-deoxy-4α-phorbol
diesters, <b>4</b>–<b>8</b>), together with 11
known phorbol diesters (nine phorbol diesters, <b>9</b>–<b>17</b>, and two 4-deoxy-4α-phorbol diesters, <b>18</b> and <b>19</b>). The structures of compounds <b>1</b>–<b>8</b> were determined by spectroscopic data information
and chemical degradation experiments. The cytotoxic activities of
the phorbol diesters were evaluated against the SNU387 hepatic tumor
cell line, and compound <b>3</b> exhibited the most potent activity
(IC<sub>50</sub> 1.2 μM)
<sup>13</sup>C-NMR spectral data of the newly isolated compounds 1, 2, 3, 4, and 5 (150 MHz in DMSO-d<sub>6</sub>, δ in ppm).
<p><sup>13</sup>C-NMR spectral data of the newly isolated compounds 1, 2, 3, 4, and 5 (150 MHz in DMSO-d<sub>6</sub>, δ in ppm).</p
The estrogen biosynthesis activity of the isolated compounds from the BPL.
<p>KGN cells were seeded in 24-well plates and pretreated with test chemicals at 50 μM for 24 h. The cells were then supplemented with 10 nM testosterone for further 24 h, and 17β-estradiol in the culture medium was quantified using a magnetic particle-based 17β-estradiol ELISA. Cont., DMSO control; FSK, 10 μM Forskolin; Let, 1 μM letrozole.</p
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