• Korean Journal of Pharmacognosy
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• v.21 no.2
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• pp.111-120
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• 1990

Five biflavones and sevenflavonolglycosideswereisolatedfromtheleaves of Ginkgo biloba. They were sciadopitysin(1), ginkgetin(2), isoginkgetin(3), bilobetin(4), amentoflavone(5), kaempferol 3-O-[$6'-O-{\rho}-coumaroyl-{\beta}-_D-glucopyranosyl(1{\rightarrow}2)-{\alpha}-_Lrhamnopyranoside$](6), quercetin 3-O-[$6'-O-{\rho}-coumaroyl-{\beta}-_D-glucopyranosyl(1{\rightarrow}2)-{\alpha}-_Lrhamnopyranoside$](8), rutinosides of kaempferol(7), isorhamnetin(9), quercetin(10), laricitrin(11), and kaempferol 3-O-($2',6'-{\alpha}-_L-dirhamnopyranosyl-{\beta}-_{D}-glucopyranoside$)(12). The structures were established by spectroscopic and chemical methods.

• Bulletin of the Korean Chemical Society
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• v.29 no.7
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• pp.1315-1319
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• 2008

A trisaccharide, 6d-Altro-Hepp$\alpha$ (1$\rightarrow$3) GlcNAc$\beta$ (1$\rightarrow$3) Gal$\alpha$ (1$\rightarrow$$OCH_2CH_2N_3$, as an O-antigenic repeating unit of Campylobacter jejuni serotypes O:23 and O:36, was synthesized. Coupling of the 6d-altro-Hepp$\alpha$ (1$\rightarrow$3) GlcNAc$\beta$ (1$\rightarrow$SEt donor with Gal$\alpha$ (1${\rightarrow}OCH_2CH_2Cl$ acceptor in the presence of NIS-TfOH promoter afforded the trisaccharide having the $\beta$ (1$\rightarrow$3) Gal linkage. $\beta$ -Stereospecificity and the desired regioselectivity for the 3-OH Gal are obtained. Subsequent hydrogenation, acetylation, azide displacement, hydrazinolysis, Nacetylation, and finally deacetylation furnished the title trisaccharide hapten for further glycoconjugation.

• Archives of Pharmacal Research
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• v.27 no.2
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• pp.143-150
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• 2004

A trisaccharide, the O-antigenic repeating unit of C. jejuni serotype O:23 and O:36, was synthesized as a 2 -azidoethyl glycoside by block addition of perbenzylated thiogalactoside donors to $\alpha$-altroHepp-(1$\rightarrow$3)-GlcNPhth disaccharide acceptor in presence of IDCP promoter. The $\alpha$-linked altroheptopyranoside moiety in the glycosyl acceptor was effectively prepared by Swern oxidation of $\alpha$-mannohepp-(1$\rightarrow$3)-GlcNPhth disaccharide followed by mild reduction with1 $NaCNBH_3$.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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• 2004.05a
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• pp.6-8
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• 2004

The NdBaCuO superconductor samples were zone-melted in low oxygen partial pressure (1 % $O_2$＋99%Ar). The zone-melting temperature was decreased about 12$0^{\circ}C$ from 1, 06$0^{\circ}C$, the zone-melting temperature in air. Thus the loss of liquid phase (BaCu $O_2$and CuO) was reduced during the zone-melting process. The content of non-superconducting phase Nd422 in zone-melted NdBaCuO samples was clearly decreased and, therefore, the substitution of Nd for Ba was occurred. The superconductivity of zone-melted N $d_{1＋x}$B $a_{2－x}$C $u_3$ $O_{y}$prepared under low oxygen partial pressure was distinctively improved.d.d.d.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2007.11a
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• pp.62-62
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• 2007

ZnO 박막이 성장된 Si기판을 이용하여 Thermal evaporation을 사용하여 온도에 따라 합성된 1-D의 구조의 ZnO nanorods의 형상과 특성에 대하여 연구를 하였다. 합성온도는 $700^{\circ}C{\sim}900^{\circ}C$를 사용하였고 온도가 낮아짐에 따라 Vertical한 1-D ZnO가 합성이 되는 것을 알 수 있었다. 특히, $700^{\circ}C$에서 합성된 1-D ZnO는 ~100nm의 폭을 가지고 800nm의 길이의 Nanorods로 성장이 되는 것을 알 수 있었고, 상온 PL측정을 통해 온도가 증가함에 따라 O 결핍 또는 Zn의 과잉에 의한 Deep level emission이 증가하는 것을 알 수 있었다.

• Journal of the Korean Applied Science and Technology
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• v.15 no.2
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• pp.25-32
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• 1998

The emulsion stability of W/O emulsion prepared by D phase emulsification during storage and handling is studied by using phase diagrams. The process of D phase emulsification begins with the formation of isotropic surfactant solution, followed by formation of oil-in-surfactant (O/D) gel emulsion by dispersion of octamethylcyclotetrasiloxane(OMCS) in the surfactant solution. Polyols were essential components for this purpose. To understand the function of polyols, the solution behavior of nonionic surfactant/oil/water/polyol systems were investigated by the ternary phase diagrams of polyoxyethylene oleyl ether/OMCS/propylene glycol(PG) aqueous solutions. The addition of PG increased the solubility of oil in the isotropic surfactant phase. D phase emulsification method has been applied to a new type of cosmetics. By using this emulsification technique, O/W emulsion were formed without a need for adjust of HLB. Fine and stable W/O emulsions were prepared by D phase emulsion.

• Korean Journal of Pharmacognosy
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• v.34 no.4 s.135
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• pp.344-351
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• 2003

Phytochemical examination of seeds of Astragalus sinicus has led to the isolation and characterization of kaempferol $3-O-{\beta}-D-apiofuranosyl-(1{\rightarrow}2)-{\alpha}-L-rhamnopyranosyl-(1{\rightarrow}6)-{\beta}-D-glucopyranoside$ (1), quercetin $3-O-{\beta}-D-xylopyranosyl-(1{\rightarrow}2)-{\beta}-D-glucopyranoside$ (2), ampelopsin (3), ampelopsin $3'-O-{\beta}-D-xylopyranoside$ (4), ampelopsin $3'-O-{\beta}-Dxylopyranoside$ (5), myricetin (6), myricetin $3'-O-{\beta}-D-glucopyranoside$ (7), myricetin $3'-O-{\beta}-D-xylopyranoside$ (8). Antioxidative activity of these compounds was determined by measuring the radical scavenging effect on 1,1-diphenyl-2-picrylhydrazyl (DPPH) radicals. Flavanonols(3,4, and 5) showed potent antioxidative activity.

• Archives of Pharmacal Research
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• v.25 no.3
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• pp.313-319
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• 2002

A total of eight flavonoids (1-8), including a novel $quercetin-7-o-(6"-o-acetyl)-{\beta}-D-glucopyranoside$ (6) and seven known flavonoids, luteolin (1), quercetin (2), luteolin $7-o-{\beta}-D-glucopyranoside$ (3), $luteolin-7-o-(6"-Ο-acetyl)-{\beta}-D-glucopyranoside$ (4) quercetin $7-o-{\beta}-D-glucopyranoside$ (5), acacetin 7-o-{\beta}-D-glucuronide (7) and apigenin-6-C-{\beta}-D-glucopyrano $syl-8-C-{\beta}-D-glucopyranoside$ (8), have been isolated from the leaves of the safflower (Carthamus tinctorius L.) and identified on the basis of spectroscopic and chemical studies. The antioxidative activity of these flavonoids was evaluated against 2-deoxyribose degradation and rat liver microsomal lipid peroxidation induced by hydroxyl radicals generated via a Fenton-type reaction. Among these flavonoids, luteolin-acetyl-glucoside (4) and quercetin-acetyl-glucoside (6) showed potent antioxidative activities against 2-deoxyribose degradation and lipid peroxidation in rat liver microsomes. Luteolin (1), quercetin (2), and their corresponding glycosides (3 & 5) also exhibited strong antioxidative activity, while acacetin glucuronide (7) and apigenin-6,8-di-C-glucoside (8) were relatively less active.

• Journal of Life Science
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• v.28 no.5
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• pp.509-516
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• 2018

Five phenolic compounds were isolated from the ethyl acetate fraction of leaves from Stewartia koreana, and their nitric-oxide (NO) inhibitory activities were measured to identify the major active constituents responsible for the efficacy of the extract against inflammatory reactions. These five compounds were quercetin (1), quercitrin (2), hyperin (3), quercetin-3-O-(6"-O-galloyl)-${\beta}$-D-galactopyranoside (4), and kaempferol 3-O-[2",6"-di-O-(trans-p-coumaroyl)]-${\beta}$-D-glucopyranoside (5). Among the separated compounds in the EtOAc fraction, compounds 4 and 5 were isolated for the first time, and no study has yet reported their anti-inflammatory effects. The compounds were identified by spectroscopic analysis, and the isolated compounds showed significant NO inhibitory effects in lipopolysaccharide (LPS)-stimulated RAW 264.7 cells. Compound 5 showed the most potent inhibitory effect (63.35% inhibition) against LPS-induced NO production compared to that of compound 1 (17.17%), compound 2 (5.0%), compound 3 (3.92%), and compound 4 (6.32%) at $10{\mu}g/ml$ concentration. NO production was inhibited by suppressing the protein expression of inducible nitric-oxide synthase in LPS-stimulated RAW 264.7 macrophages. These results indicate that kaempferol 3-O-[2",6"-di-O-(trans-p-coumaroyl)]-${\beta}$-D-glucopyranoside might be the major active compound responsible for the anti-inflammatory effects of S. koreana.

• The Korean Journal of Food And Nutrition
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• v.10 no.1
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• pp.102-109
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• 1997

The structures of novel branched oligosaccharides synthesized by the acceptor reaction with dextransucrase from Leuconostoc mesenteriodes M-12 were proposed in accordance with the results obtained from enzymatic hydrolyses and a partial acid hydrolysis. The structure of branched oligosaccharide B4 was shown to be 62-O-$\alpha$-D-kojibiosylmaltose. Branched oligosaccharide B5 was shown to be 63-O-$\alpha$-D-kojibiosylpanose. By reacting the acceptor reaction products with endodextranase a novel branched oligosaccharide (D4) could be produced. D4 was derived from the result of endodextranase hydrolysis of oligosaccarides synthesized by the second acceptor reaction with dextransucrase and was resistant to endodextranase and glucoamylase. The proposed structure of D4 was 62-O-$\alpha$-D-kojibiosylisomaltose. Formation pattern of the acceptor reaction products smaller than d.p. 6 with linear or branched linkage was also shown.