• Fibers and Polymers
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• v.2 no.3
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• pp.122-128
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• 2001

UV-curable polyurethane acrylate prepolymers were prepared from diisocyanates [isophorone diisocyanate (IPDI), 2,4-toluene diisocyanate (TDI), or 4,4'-dicyclohexylmethane diisocyanate (H$_{12}$MDI)], diols [ethylene glycol (EG), 1,4-butane diol (BD), or 1,6-hexane diol (HD)], polypropylene glycol as a polyol. UY-curable mixtures were formulated from the prepolymer (90 wt%), reactive diluent monomer trimethylol propane triacrylate (10 wt%). and photoinitiator 1-hydroxycy-clohexyl ketone (3 wt% based on prepolymer/diluent). The effects of different diisocyanates/low molecular weigh dial on the dynamic mechanical thermal properties and elastic recovery of UV-cured polyurethane acrylate films were examined. The tensile storage modulus increased a little in the order of EG > BD > HD at the same diisocyanate. Two loss modulus peaks for all samples are observed owing to the glads transition of softs segments ($T_gh$) and the glass transition temperature of hard segments ($T_gh$). For the same diisocyanate, $T_gh$, decreased, however, $T_gh$ increased, in the order of HD > BD > EG. The elastic recovery also increased in the order of HD > BD > EG at the same diisocyanate. In case of same diols, $T_gh$ increased in the order of $H_12$MDl > TDI > IPDI significantly. The ultimate elongation and elastic recovery increased in the order of TDI > IPDI > $H_12$MDl at the same diol.l.

• Polymer(Korea)
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• v.34 no.6
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• pp.507-510
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• 2010

Poly(cyclohexane carbonate) diol was synthesized by the alternating copolymerization of cyclohexene oxide and $CO_2$ over Cr based transition metal catalysts. The prepared PCCD was applied as a precursor for the preparation of waterborne polyurethane (PUD) in order to investigate an application field of carbon dioxide-based polycarbonate. The scratch resistance and thermal properties of PUDs, which was prepared with two kinds of polymeric diols (PCD and PCCD) were investigated. The scratch resistance and thermal decomposition temperature of PUD film prepared with PCCD is worse than those prepared with PCD, poly(hexamethylene carbonate) glycol. While, glass transition temperature of PUD film prepared with PCCD was higher than that prepared with PCD. It might be due to the rigid cyclohexane structure in the PCCD.

• Journal of Ginseng Research
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• v.39 no.1
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• pp.54-60
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• 2015

Background: The present study was designed to prepare and find the optimum active preparation or fraction from Korea Red Ginseng inhibiting matrix metalloproteinase-13 (MMP-13) expression, because MMP-13 is a pivotal enzyme to degrade the collagen matrix of the joint cartilage. Methods: From total red ginseng ethanol extract, n-BuOH fraction (total ginsenoside-enriched fraction), ginsenoside diol-type-enriched fraction (GDF), and ginsenoside triol-type-enriched fraction (GTF) were prepared, and ginsenoside diol type-/F4-enriched fraction (GDF/F4) was obtained from Panax ginseng leaf extract. Results: The n-BuOH fraction, GDF, and GDF/F4 clearly inhibited MMP-13 expression compared to interleukin-$1{\beta}$-treated SW1353 cells (human chondrosarcoma), whereas the total extract and ginsenoside diol-type-enriched fraction did not. In particular, GDF/F4, the most effective inhibitor, blocked the activation of p38 mitogen-activated protein kinase (p38 MAPK), c-Jun-activated protein kinase (JNK), and signal transducer and activator of transcription-1/2 (STAT-1/2) among the signal transcription pathways involved. Further, GDF/F4 also inhibited the glycosaminoglycan release from interleukin-$1{\alpha}$-treated rabbit cartilage culture (30.6% inhibition at $30{\mu}g/mL$). Conclusion: Some preparations from Korean Red Ginseng and ginseng leaves, particularly GDF/F4, may possess the protective activity against cartilage degradation in joint disorders, and may have potential as new therapeutic agents.

• Journal of the Korean Society of Food Science and Nutrition
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• v.12 no.1
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• pp.37-40
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• 1983

To determine harvesting time of ginseng, the changes of saponin contents and PT/PD ratios of triol saponin vs. diol saponin in relation to root age of Panax ginseng. Total saponin contents were increased in relation to root age, 5-years was higher than 6-years for saponin contents. Therefore, it considered that can be obtained the desired results to harvest at 5-years. Also, PT/PD ratios were increased in relation to root age, 6-years was highest. Considering PT/PD ratios in relation with pharmaceutical action, it must be harvested at 6-years.

• Bulletin of the Korean Chemical Society
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• v.7 no.3
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• pp.179-182
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• 1986

A major polyacetylene compound from Panax ginseng roots, heptadeca-1-en-4,6-diyn-3,9,10-triol, was irradiated with 300 nm UV light to obtain a photooxidized acetylenic compound having the conjugated en-on-diyne chromophore, heptadeca-1-en-4,6-diyn-9,10-diol-3-one. The same oxidation product was obtained exclusively by 4-(dimethylamino) pyridinium chlorochromate at room temperature.

• Natural Product Sciences
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• v.6 no.2
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• pp.102-105
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• 2000

Chemical investigation of the hot hexane extract of the stem bark of Gordonia dassanayakei afforded a new oleanane triterpenoid, $11{\alpha},13{\beta}-dihydroxyolean-3,12-dione$ (1) and two other oleanane triterpenoids, $3{\beta}-acetoxy-11{\alpha},13{\beta}-dihydroxyolean-12-one\;(2)\;and\;3{\beta},11{\alpha}-diacetoxy-13{\beta}-hydroxyolean-12-one\;(3)\;and\;a\;hopane\;6{\alpha},22-diol$ (4), which are new to the plant.

• Journal of the Korean Wood Science and Technology
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• v.34 no.3
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• pp.64-72
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• 2006

Two compounds were isolated from the diethylether and ethyl acetate fraction of hot water extracts by TLC and column chromatography as dyeing components. The isolated compounds were characterized as H-dibenzoquinoline-2,10-diol,5,6,6a,7-tetrahydro-1,9-dimethoxy-6-methyl (compoundI) and lyoniresinol (compoundII) by NMR and Mass spectrophotometry. To investigate if the isolated compounds are involved in the dyeing process, HPLC analysis was used. The retention time of the components from dye used in the study and the dye decolorized from the dyed substrate, silk by ethyl acetate were compared to conform the identity of those compounds. The retention time of the components from the dye and decolorized solution were identical. As a results, those two compounds were considered as dye bound to the silk.

• Textile Coloration and Finishing
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• v.11 no.4
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• pp.1-7
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• 1999

Urethane-acrylate propelymers for secondary coating of optical fiber and high - performance material were prepared from the 4,4'-diphenylmethane diisocyanate(MDI), poly(tetramethylene oxide)glycol(PTMG, Mw 650 or 1000), 1,6-hexanediol(HD), 2-hydroxyethyl acrylate(HEA), and dibutyltin dilaurate as a catalyst. UV-Curable polyurethane acrylates were formulated from the urethane-acrylate prepolymers, three types of reactive diluents(DTs) having mono-, di-, and trifunctional-phenoxyethyl acrylate(PEA), hexanediol diacrylate(HDDA), and trimethylolpropane triacrylate(TMPTA), and 1-hydtoxycyclohexyl phenyl ketone(Irgacure 184) as a photoinitiator. The UV-cured films of polyurethane acrylates were obtained by curing using a medium-pressure mercury lamp(U W/cm, $\lambda_{max}=365\;nm)$. In this work, the effects of molecular weights of polyol and diol with low molecular weight into polymer chain on mechanical and dynamic mechanical properties of UV-cured polyurethane acrylates were studied. The structure and properties of the films obtained from the UV photopolymerization of urethane-acrylate prepolymer were investigated by FT-IR spectroscopy, dynamic mechanical measurement, tensile testing, and X-ray diffractometry.

• KSBB Journal
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• v.18 no.2
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• pp.100-106
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• 2003

An on-line frontal analysis HPLC system was developed to determine the unbound concentration of (S)-perillyl alcohol, an potential anti-cancer agent, in human serum albumin (HSA) solution, The analysis was performed on a Develosil 100 Diol 5 (10 cm x 4.6 mm I.D.) high-performance frontal analysis (HPFA) column. Sodium phosphate solution was used as the mobile phase (pH 7.4, ionic strength 0.17) at a flow rate of 1 $m\ell$/min. UV wavelength was set at 205 nm. A injection volume of 600${mu}ell$ was chosen to ensure the compound eluted formed a zonal peak with a plateau. By Scatchard analysis, it was found that the binding constant(K) and binding number(n) of (S)-perillyl alcohol to molecular HSA were 2.05 x $10^6$ [$M{-1}$], 0.00428, respectively.

• Natural Product Sciences
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• v.28 no.1
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• pp.6-12
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• 2022

Five sesquiterpenoids, 7-epi-eudesm-4(15)-ene,1β,6α-diol (1), 7-epi-eudesm-4(15)-ene,1β,6α-diol (2), saniculamoid D (3), aphanamol I (4), and 4β,10α-dihydroxyaromadendrane (5), were isolated from the stem bark of Aglaia grandis. The compounds' (1-5) chemical structures were identified by spectroscopic data including, IR, NMR (¹H, ¹³C, DEPT 135°, HMQC, HMBC, ¹H-¹H COSY), and HRTOFMS, as well as by comparing with the previously reported spectral data. Therefore, this study described the structural elucidation of compounds 1-5 and evaluated their cytotoxic effects against Hela cervical and B16F10 melanoma cells for the first time, but no significant result was discovered.