• Title/Summary/Keyword: S4

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Synthesis of a Precursor of Bulgecinine, (4S,5R)-1-Acetyl-2-formyl-5-benzyloxymethyl-4-pyrrolidinol (Bulgecinine 선구물질인 (4S,5R)-1-Acetyl-2-formyl-5-benzyloxymethyl-4-pyrrolidinol의 합성)

  • Jeon, Hak Rim;Yoon, Shin Sook;Shin, Young Sook;Nam Shin, Jeong E.
    • Journal of the Korean Chemical Society
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    • v.41 no.3
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    • pp.150-156
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    • 1997
  • A precursor of bulgecinine, (4S,5R)-1-acetyl-2-formyl-5-benzyloxymethyl-4-pyrrolidinol (15) has been synthesized from diacetone-D-glucose. Barton deoxygenation, conversion to an L-sugar and displacement with $N_3^-$ at C-5, and one-pot reductive cyclization at C-2 produced (6R)-6-Ο-benzyloxymethyl-(3R)-3-methoxy-2-oxa-5-azabicyclo-[2,2,1]heptane(13), a key intermediate for bulgecinine. N-Acetylation and acid hydrolysis of 13 furnished a precursor of bulgecinine, (2S,4S,5R)-pyrrolidinol derivative 15 and its (2R,4S,5R)-diastereomer.

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Synthesis of SrGa2S4 Phosphor and Its Luminescent Properties (SrGa2S4 형광체의 합성과 발광 특성)

  • Heo, Yeong-Deok;Sim, Jae-Hun;Do, Yeong-Rak
    • Journal of the Korean Chemical Society
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    • v.46 no.2
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    • pp.164-168
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    • 2002
  • SrGa$_2$S$_4$ : Eu is a green emitting phosphor which is applied for field emission display, and cathodoluminescence. Conventionally, SrGa$_2$S$_4$ : Eu is synthesized by solid state reaction, in which a mixture of SrCO$_3$, Ga$_2$O$_3$, and Eu$_2$O$_3$ is fired at high temperatures under flowing H$_2$S and Ar gases. In this study,SrGa$_2$S$_4$ : Eu phosphor is synthesized by using a decomposition method, where SrS, Eu complex, and Ga com-plex are used. The advantage of this method is that toxic H$_2$S gas and Ar gas are not used. The synthetic con-ditions and luminescent properties of SrGa$_2$S$_4$ : Eu phosphor are also investigated.

A Study on the Expression of Glycosaminoglycans in the Experimental Tooth Movement of Rat and in Cultured Periodontal Ligament Cells (실험적 치아이동시 glycosaminoglycan의 발현에 관한 연구)

  • Lee, Kyung-Hwan;Lee, Jong-Jin;Kang, Kyung-hwa;Kim, Eun-Cheol;Kim, Sang-Cheol
    • The korean journal of orthodontics
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    • v.31 no.4 s.87
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    • pp.447-458
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    • 2001
  • The purpose of this study was to evaluate 1) in vivo, the expression of chondroitin 4-sulfate (CH-4S), a structural element of glycosaminoglycans(GAGs), in periodontal tissue during the experimental movement of rat incisors, by labelled streptavidine biotin immunohistochemical staining for CH-4S, 2) In vitro, the expression of CH-4S in cultured human periodontal ligament(PDL) cells supplemented with 10ng/ml of $TGF-{\beta}_1$, 20ng/ml of PDGF-BB, 1ng/ml $TNF-\alpha$, or $1{\mu}g/ml$ LPS by western blot analysis. The results of this study were as follows ; 1. The expression of CH-4S was stronger in pulp, PDL, osteoblasts, osteoclasts and osteocytes in experimental group than in control group, but was rare in dentin, and cementum of experimental groups, regardless of the duration of force application, which was not different from that of control group. 2. In experimental group, the expression of CH-4S in pulp began to increase at 1 day after force application and got to the highest degree at 7 days. After 14 days, the expression in CH-4S immunoreactivity was decreased, and became similar to that of control group at 28 days. 3. The expression of CH-4S in PDL was noted in adjacent to alveolar bone. PDL showed higher intensity of immunolabelling after 1 day of orthodontic tooth movement. And the expression was more stronger in the tension side than that of pressure side of PDL at 1 day, but more stronger in the pressure side than that of tension side of PDL at 4 days. After 7 days, a decrease in CH-4S expression was observed. 4. The expression of CH-4S in alveolar bone got to the highest degree at 4 days, and At 7 days, a decrease in CH-4S expression was observed. 5. PDGF-BB notably raised the expression of CH-4S in the PDL cells at 3 days of cultivation 6. The expression of CH-4S of PDL cells was decreased with the application of $TNF-\alpha$ at 1 day. 7. Admixture of $TGF-{\beta}_1$ and PDGF-BB got more expression of CH-4S in PDL as compared to only $TGF-{\beta}1$ or PDGF-BB. A similar decrease of the expression of CH-4S was observed in the case of application of LPS or $TNF-\alpha$.

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Synthesis and Characterization of Optically Active mer-[Co(L)2](CIO4)[L=4(S)-1-(2-pyridyl)-3-oxo-4-amino-2-azapentane(S-alaampH) and 4(S)-1-(2-pyridyl)-3-oxo-4-aza-7-thiaoctane (S-metampH)] (광학활성인 mer-[Co(L)2](CIO4)착물의 합성과 성질 [L=4(S)-1-(2-pyridyl)-3-oxo-amino-2-azapentane(S-alaampH)와 4(S)-1-(2-pyridyl)-3-oxo-4-aza-7-thiaoctane (S-metampH)])

Synthesis of Cephalosporin Derivatives with Triazolylthiomethylpyrrolidines at the C-3 Side Chain (트리아조릴 티오메칠피로리딘을 3번 측쇄에 가진 세파로스포린 유도체의 합성)

  • 고옥현;홍준희
    • YAKHAK HOEJI
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    • v.46 no.5
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    • pp.313-319
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    • 2002
  • Synthesis of 7$\beta$-[(Z)-2-(2-aminothiazol-4-yl)-2-(1-carboxy-1-methylethoxyimino)acetamido]-3-[[(3S, 5S)-5-[4-phenyl-5-(4-methylphenyl or 2-thiophenyl)-4H-l, 2, 4- triazol-3-yl]thiomethylpyrrolidin-3-yl]]thiomethyl-3-cephem-4-carboxylic acids (7a, 7b) were described. (2S, 4S)-4-acethylthio-2-[4-phenyl-5-(4-methylphenyl or 2-thiophenyl)-4 H-1, 2, 4-triazol-3-yl]thiomethyl-1-tert-butoxycarbonylpyrrolidines (4a, 4b) were prepared from trans-4-hydroxy-L-proline with (2S, 4R)-absolute configuration as starting material. 4-Phenyl-5-(4-methylphenyl or 2-thiophenyl)-4 H-l, 2, 4-triazol-3-thiols (2a, 2b) were prepared from p-toluic anhydride and 2-thiophene carboxylic acid hydrazide, respectively. p-Methoxybenzyl 7$\beta$-(Z)-2-(2-for-mamidothiazol-4-yl)-2-(1-tert-butoxycarbonylisopropylimino]acetamido-3-[[ (3S, 5S)-5-[4-phenyl-5-(4-methylphenyl or 2-thio phenyl)-4H-1, 2, 3-triazol-3-yl]thiomethyl-1- tert-butoxycarbonylpyrrolidin-3-yl]]thiomethyl-3-cephem-4-carboxylates (6a, 6b) were achieved by using p-methoxybenzyl ]7P-(Z)-2-(2-formamidothiazol-4-yl)-2-(tert-butoxycarbonylisopropylimino] acetamido-3-chloromethyl-3-cephem-4-carboxylate (5) and (2S, 4S)-4-acethylthio-2-[4-phenyl-5-(4-methyl phenyl or 2-thiophenyl)-4H-1, 2, 4-triazol-3-yl]thiomethyl-1-tert-butoxycarbonyl pyrrolidines (4a, 4b). Removal of formyl, Boc, and p-methoxybenzyl protecting groups were carried out by triflu oroacetic acid and anisole to give the target compounds.

Synthesis and Characterization of Soluble Polypyrrole with High Conductivity (높은 전기 전도성을 갖는 가용성 폴리피롤 합성 및 특성)

  • Hong, Jang-Hoo;Jang, Kwan-Sik
    • Applied Chemistry for Engineering
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    • v.18 no.3
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    • pp.234-238
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    • 2007
  • Highly conducting Polypyrroles soluble in organic solvents were synthesized using functional doping agents, such as mixed dopants [sodium di(2-ethylhexyl)sulfosuccinate (DEHSNa) Naphthalenesulfonic acid (NSA), DEHSNa Toluenesulfonic acid (TSA), DEHSNa Dodecylbenzensulfonic acid (DBSA)] and mixed oxidants [$(NH_4)_2S_2O_8{\cdot}FeCl_3$, $(NH_4)_2S_2O_8{\cdot}Fe_2(SO_4)_3$]. Ppy-DEHS powder using an oxidant, such as $(NH_4)_2S_2O_8$ (10 wt%/vol.) showed higher solubility than the mixed dopant (DEHSNa NSA, 3 wt%/vol.) and mixed oxidant [$(NH_4)_2S_2O_8{\cdot}Fe_2(SO_4)_3$, 4 wt%/vol.] in DMF solvent. But Ppy-DEHS free standing film using a mixed dopant, such as DEHSNa NSA (16 S/cm) and a mixed oxidant, such as $(NH_4)_2S_2O_8{\cdot}Fe_2(SO_4)_3$ (13 S/cm) cast from DMF solvent showed higher electrical conductivity than $(NH_4)_2S_2O_8$ (2 S/cm). For the Ppy-DEHS films using various condition cast from DMF solvent, three dimensional various range hopping model (3D VRH ; $\{{\sigma}_{dc}(T)={\sigma}_oexp[-(T_o/T)^{1/4}]\}$) provided fit to the results of temperature dependence of electrical conductivity measurement.

The Growth and Energy Gap Measurement of $ZnGa_2S_4 and Zn$a_2S_4$: Co Crystals ($ZnGa_2S_4 및 Zn$a_2S_4$ : Co 결정의 합성과 Energy Gap 측정)

  • Kim, Hyung-Gon
    • Journal of the Korean Institute of Telematics and Electronics
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    • v.26 no.11
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    • pp.1814-1818
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    • 1989
  • The crystals of ZnGa2S4 and ZnGa2S4:Co(2mole%) were synthesized from high-purity (99.999%) elements of Zinc, Gallium, and sulfur. The crystal structure of these crystals belong to a tetragonal system with layer type and the lattice constants are a =5.35\ulcorner c=10.43\ulcornerfor ZnGa2S4: Co(2 mole%) crystal at 298\ulcorner. The optical absorption spectra of these compounds were obtained through reflectance measurements using a 60 mm diameter intergrating sphere. The optical energy gaps are 3.18eV for ZnGa2S4 and 2.60eVfor ZnGa2S4:L Co(2mole%)at 298\ulcorner, respectively.

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Effects of Dolsan Leaf Mustard Powder on the Quality of Frying Batter (돌산갓 분말 첨가가 튀김반죽의 품질에 미치는 영향)

  • Oh, SunKyung;Choi, MyeongRak
    • Journal of Life Science
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    • v.29 no.12
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    • pp.1364-1370
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    • 2019
  • The anti-oxidant activity, sinigrin content, and sensory evaluation of frying batter treated with Dolsan leaf mustard powder (DLMP) were investigated. These endpoints were measured in the control sample (batter without DLMP) and seven other batters with the addition of DLMP in the following quantities: 0.03 g (S-1), 0.02 g (S-2), 0.06 g (S-3), and 0.3 g (S-4, S-5, S-6, and S-7 with different amounts of red pepper powder). The acid value (AV) and peroxide value (POV) were low in the S-4 and S-5 batters; the total polyphenol content was 190.97 mg GAE/g in the control sample and 721.17 mg GAE/g in S-4; and the total flavonoid content of S-6 was 67.82 mg QE/g which was higher than that of the control sample. The anti-oxidant activity was measured by EDA, ABTS, and FRAP assays and was seen to rise as the amount of DLMP increased. Moreover, sinigrin content was higher in S-4, S-5, S-6, and S-7 than in the control, S-1, S-2, and S-3, and there were no significant differences among S-4 to S-7 when just 0.3 g of DLMP was added. Sensory evaluation showed that color, flavor, taste, texture, and overall acceptability values were significantly higher in S-4 and S-5, and that there was no significant difference across the samples. The addition of DLMP is therefore expected to increase the anti-oxidant activity of frying batter which would be effective in improving the storage and quality of the product.

Antibiofilm Activity and Binding Specificity of Polyclonal DNA Aptamers on Staphylococcus aureus and Escherichia coli

  • Arizah Kusumawati;Apon Zaenal Mustopa;Rifqiyah Nur Umami;Adi Santoso;I Wayan Teguh Wibawan;Agus Setiyono;Mirnawati Bachrum Sudarwanto
    • Microbiology and Biotechnology Letters
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    • v.50 no.3
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    • pp.328-336
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    • 2022
  • Aptamers are short, chemically synthesized, single-stranded DNA or RNA oligonucleotides that fold into unique three-dimensional structures. In this study, we aim to determine the antibiofilm activity and binding specificity of the six polyclonal DNA aptamers (S15K3, S15K4, S15K6, S15K13, S15K15, and S15K20) on Staphylococcus aureus BPA-12 and Escherichia coli EPEC 4. Aptamer S15K6 showed the highest percentage of antibiofilm activity against S. aureus BPA-12 (37.4%) as shown by the lowest OD570 value of 0.313. Aptamer S15K20 showed the highest percentage of antibiofilm activity against E. coli EPEC 4 (15.4%) as shown by the lowest OD570 value of 0.515. Aptamers S15K13 and S15K20 showed antibiofilm activities against both S. aureus BPA-12 and E. coli EPEC4, and thus potentially have broad reactivity. Furthermore, based on the binding capacity and Kd values from our previous study, the binding specificity assay of selected polyclonal DNA aptamers (S15K3 and S15K15) against S. aureus BPA-12, E. coli EPEC 4, S. aureus BPA-6, S. agalactiae, E. coli MHA-6, and Listeria monocytogenes were performed using qPCR. Aptamers S15K3 and S15K15 showed specific binding to S. aureus BPA-12, E. coli EPEC 4, S. aureus BPA-6, and S. agalactiae, but could not bind to E. coli MHA-6 and L. monocytogenes. Therefore, this study showed that the polyclonal DNA aptamers have antibiofilm activity and were able to bind to S. aureus BPA-12 and E. coli EPEC 4 bacteria.

Direct Geo-referencing for Laser Mapping System

  • Kim, Seong-Baek;Lee, Seung-yong;Kim, Min-Soo
    • Proceedings of the KSRS Conference
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    • 2002.10a
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    • pp.423-427
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    • 2002
  • Contrary to the traditional text-based information, 4S(GIS,GNSS,SIIS,ITS) information can contribute to the citizen's welfare in upcoming era. Recently, GSIS(Geo-Spatial Information System) has been applied and stressed out in various fields. As analyzed the data from GSIS arena, the position information of objects and targets is crucial and critical. Therefore, several methods of getting and knowing position are proposed and developed. From this perspective, Position collection and processing are the heart of 4S technology. We develop 4S-Van that enables real-time acquisition of position and attribute information and accurate image data in remote site. In this study, the configuration of 4S-Van equipped with GPS, INS, CCD and eye-safe laser scanner is shown and the merits of DGPS/INS integration approach for geo-referencing is briefly discussed. The algorithm of DGPS/INS integration fur determination of six parameters of motion is eccential in the 4S-Van to avoid or simplify the complicated computation such as photogrammetric triangulation. 4S-Van has the application of Laser-Mobile Mapping System for three-dimensional data acquisition that merges the texture information from CCD camera. The technique is also applied in the fields of virtual reality, car navigation, computer games, planning and management, city transportation, mobile communication, etc.

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