• Journal of the Korean Chemical Society
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• v.28 no.1
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• pp.14-19
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• 1984

The stability difference of metmyoglobin in $H_2O$ and $D_2O$ at pH 5.7 and pH 7.0 toward pressure denaturation is studied. Metmyoglobin is denatured in $D_2O$ at smaller pressure than in $H_2O$. The stability difference in $H_2O$ and $D_2O$ is more pronounced at pH 5.7 than at pH 7. The main reasons for the stability difference in $H_2O$ and $D_2O$are the difference in positive charge due to $H^+$and $D^+$ binding to the protein in $H_2O$ and $D_2O$, and the structural change that accompany deuteration.

• Korean Journal of Pharmacognosy
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• v.30 no.2
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• pp.168-172
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• 1999

Five compounds were isolated from the roots of Polygala tenuifolia (Polygalaceae). On the basis of spectroscopic evidences, the structures of these compounds were characterized as ${\alpha}-D-(6-O-sinapoyl)-glucopyranosyl(1{\rightarrow}2')-{\beta}-D-(3'-O-sinapoyl)-fructofuranoside$ (P3), ${\alpha}$-D-{6-O-(p-methoxybenzoyl)}-glucopyranosyl-$(1{\rightarrow}2')$-${\beta}$-D-{3'-O-(3',4',5'-trimethoxycinnamoyl)}-fructofuranoside(P4), ${\alpha}$-D-{6-O-(p-hydroxybenzoyl)}-glucopyranosyl-$(1{\rightarrow}2')$-${\beta}$-D-{3'-O-(3',4',5'-trimethoxycinnamoyl)}-fructofuranoside(P5), ${\alpha}-D-glucopyranosyl-(1{\rightarrow}2')-{\beta}-D-(1'-O-sinapoyl)-fructofuranoside$(P6), $1,5-anhydro-D-glucitol$(P7) respectively. ${\alpha}$-D-{6-O-(p-Methoxybenzoyl)}-glucopyranosyl-$(1{\rightarrow}2')$-${\beta}$-D-{3'-O-(3',4',5'-trimethoxycinnamoyl)}-fructofuranoside(P4) and ${\alpha}-D-glucopyranosyl-(1{\rightarrow}2')-{\beta}-D-(1'-O-sinapoyl)-fructofuranoside$(P6) were isolated for the first time from the genus of Polygala. 1,5-Anhydro-D-glucitol(P7) was isolated without hydrolysis for the first time from the root of Polygala tenuifolia.

• Journal of the Korean Chemical Society
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• v.23 no.1
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• pp.46-51
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• 1979

Condensation of 3,4,6-tri-O-acetyl-2-deoxy-2-phthalimido-${\beta}$-D-glucopyranosyl bromide (2) with 1,2;3,4-di-O-isopropylidene-${\alpha}$-D-galactopyranose (3) in the presence of silver triflate and syn-collidine gave 1,2;3,4-di-O-isopropylidene-6-O-(3,4,6-tri-O-acetyl-2-deoxy-2-phthalimido-${\beta}$-D-glucopyranosyl)-${\alpha}$-D-galactopyranose (4) in $86{\%}$ yield. Cleavage of phthalimido group and de-O-acetylation with hydrazine, acetylation, and hydrolysis of isopropylidene and O-acetyl groups furnished 6-O-(2-acetamido-2-deoxy-${\beta}$-D-glucopyranosyl)-D-galactopyranose (1) with overall yield of $65.8{\%}$ starting from 3. Some other derivatives of 1 which have free hydroxyl groups at the specific position have also been prepared from 4. These compounds could be used as precursors for further glycosidation reactions.

• Korean Journal of Optics and Photonics
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• v.19 no.6
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• pp.435-438
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• 2008

D2O, which is used in nuclear power generation, is slightly different from $H_2O$. $D_2O$ consists of deuterium (D), which is an isotope of hydrogen (H) and has one more neutron than H. $D_2O$ is heavier by about 11% than $H_2O$, and $D_2O$ is present in water in natureat about 0.002%. Its melting point and boiling point are $3.81^{\circ}C$ and $101.42^{\circ}C$, respectively. $D_2O$ is harmful to the human body if it replaces water in the human body by more than $25%{\sim}50%$. We have measured the index of refractive and power absorption of 0%, 25%, 50%, 75%, and 100% of $D_2O$ in $H_2O$ using terahertz time-domain spectroscopy, and we have found that the refractive index decreases and power absorption also decreases as the concentration of $D_2O$ increases.

• YAKHAK HOEJI
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• v.54 no.6
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• pp.441-448
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• 2010

In present study, classification and quality control of Genus Polygonatum were developed using the isolated from Polygonati Odorati Rhizoma and Polygonati Rhizoma. 3 components were isolated from Butanol fractions of Polygonati Rhizoma, and 2 components were isolated from Hexane and Butanol fractions of Polygonati Odorati Rhizoma. All the components were obtained using silica gel and ODS column chromatography. The compounds were identified as adenosine, 14-hydroxylfurost-5-ene-3-O-${\beta}$-D-glucopyranosyl-($1{\rightarrow}2$)-O-${\beta}$-D-glucopyranosyl-($1{\rightarrow}4$)-O-${\beta}$-D-galactopyranosyl-26-O-${\beta}$-D-glucopyranoside, 22-O-methyl-14-hydrocxyfurost-5-ene-3-O-${\beta}$-D-glucopyranosyl-($1{\rightarrow}2$)-O-${\beta}$-D-glucopyranosyl-($1{\rightarrow}4$)-O-${\beta}$-Dgalactopyranosyl-26-O-${\beta}$-D-glucopyranoside, ${\beta}$-Sitosteryl-3-O-${\beta}$-D-D-glucopyranoside, 14-hydoxylfurost-5-ene-3-O-${\beta}$-Dglucopyranosyl-($1{\rightarrow}2$)-O-[${\beta}$-D-xylopyranosyl-($1{\rightarrow}3$)]-O-${\beta}$-D-glucopyranosyl-($1{\rightarrow}4$)-O-${\beta}$-D-galactopyranoside through physicochemical data, spectroscopic methods ($^1H$-NMR, $^{13}C$-NMR, Mass) according references. The quality control of genus Polygonatum were conducted using HPLC quantitative analysis of 14-hydroxylfurost-5-ene-3-O-${\beta}$-D-glucopyranosyl-($1{\rightarrow}2$)-O-${\beta}$-D-glucopyranosyl-($1{\beta}4$)-O-${\beta}$-D-galactopyranosyl-26-O-${\beta}$-D-glucopyranoside, 14-hydoxylfurost-5-ene-3-O-${\beta}$-D-glucopyranosyl-($1{\rightarrow}2$)-O-[${\beta}$-D-xylopyranosyl-($1{\rightarrow}3$)]-O-${\beta}$-D-glucopyranosyl-($1{\rightarrow}4$)-O-${\beta}$-D-galactopyranoside in 30 samples collected throughout Korea and China. This method provided a tool for standardization of mix or misusing the commercial Odorati Rhizoma and Polygonati Rhizoma. As a result, contained quantity of 14-hydroxylfurost-5-ene-3-O-${\beta}$-D-glucopyranosyl-($1{\rightarrow}2$)-O-${\beta}$-D-glucopyranosyl-($1{\rightarrow}4$)-O-${\beta}$-D-galactopyranosyl-26-O-${\beta}$-D-glucopyranoside was measured $0.008{\pm}0.006%$ and 14-hydoxylfurost-5-ene-3-O-${\beta}$-D-glucopyranosyl-($1{\rightarrow}2$)-O-[${\beta}$-D-xylopyranosyl-(13)]-O-${\beta}$-D-glucopyranosyl-($1{\rightarrow}4$)-O-${\beta}$-Dgalactopyranoside was measured $0.026{\pm}0.012%$.

• Bulletin of the Korean Chemical Society
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• v.14 no.2
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• pp.188-191
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• 1993

The reaction between methyl 2,3-di-O-benzyl-4,6-di-O-mesyl-${\alpha}$-D-glucopyranoside (1b) and potassium superoxide resulted in hydrolysis, and gave methyl 2,3-di-O-benzyl-${\alpha}$-D-glucopyranoside (1) as a sole product. When the reaction was performed with a vicinal dimesylate, methyl 4,6-O-benzylidene-2,3-di-O-mesyl-${\alpha}$-D-altropyranoside (4b), again the hydrolysis product, methyl 4,6-O-benzylidene-${\alpha}$-D-altropyranoside (4) was obtained. However, the reaction of potassium superoxide with another vicinal dimesylate, methyl 4,6-O-benzylidene-2,3-di-O-mesyl-${\alpha}$-D-glucopyranoside (3b), nucleophilic displacement took place to afford methyl 4,6-O-benzylidene-${\alpha}$-D-altropyranoside (4). Apparently different results from two trans vicinal dimesylates, 3b and 4b are explained by the transient formation of epoxides, methyl 2,3-anhydro-4,6-O-benzylidene-${\alpha}$-D-allopyranoside (8) and methyl 2,3-anhydro-4,6-O-benzylidene-${\alpha}$-D-mannopyranoside (9) by $KO_2$. The reaction between the allo epoxide 8 and $KO_2$ gave altro 4. The manno epoxide 9 also afforded altro 4 as the major product. Facile epoxide formation by the reaction of a vicinal dimesylate and superoxide was also observed with 3-O-benzyl-1,2-O-isopropylidene-5,6-di-O-mesyl-${\alpha}$-D-glucofuranose: 5,6-anhydro-3-O-benzyl-1,2-O-isopropylidene-${\beta}$-L-idofuranose was obtained.

• Archives of Pharmacal Research
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• v.22 no.4
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• pp.423-427
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• 1999

A study was carried out to evaluate flavonol glycosides in leaves of Symplocarpus renifolius (Araceae). From the water fraction of the MeOH extract, three new flavonol glycosides were isolated along with three known compounds, Kaempferol-3-O-$\beta$-glucopyranosyl-($1{\rightarrow}2$)-$\beta$-D-glucopyranosyl-7-O-$\beta$-D-glucopyranoside, quercetin-3-O-$\beta$-D-glucopyranosy-1-($1{\rightarrow}2$)-$\beta$-D-glucopyranoside, and caffeic acid. The structures of the new flavonol glycosides were elucidated by chemical and spectral analyses a quercetin-3-O-$\beta$-D-glucopyranosyl-($1{\rightarrow}2$)-$\beta$-D-glucopyranosyl-7-O-$\beta$-D-glucopyranoside, isorhamnetin-3-O-$\beta$-D-glucopyranosyl-(1 2)-$\beta$-D-glucopyranosyl-7-O-$\beta$-D-glucopyranosdie, and quercetin-3-O$\beta$-D-glucopyranosyl-($1{\rightarrow}2$)-$\beta$-D-glycopyranosyl-7-O-($6^{IIII}$-trans-caffeoyl)-$\beta$-D-glucopyranoside.

• Natural Product Sciences
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• v.4 no.4
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• pp.268-273
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• 1998

Two new triterpenoid saponins, named segetoside D and E, have been isolated from the seeds of Vaccaria segetalis. On the basis of chemical reactions and spectral data, structures of segetoside D and E have been established as: $28-O-[{\beta}-D-xylopyranosyl-(1{\rightarrow}4)-{\alpha}-L-rhamnopyranosyl-(1{\rightarrow}2)]-[5-O-acetyl-{\alpha}-arabinofuranosyl(1{\rightarrow}3)]-[4-O-acetyl-{\beta}-D-fucopyranosyl]-quillaic\;acid-3-O-[{\beta}-D-galactopyranosyl(1{\rightarrow}2)]6-O-methyl\;ester-{\beta}-D-glucuronopyranoside$ and $28-O-[{\beta}-D-xylopyranosyl-(1{\rightarrow}4)-{\alpha}-L-rhamnopyranosyl-(1{\rightarrow}2)]-[5-O-acetyl-{\alpha}-arabinofuranosyl(1{\rightarrow}3)]-[4-O-acetyl-{\beta}-D-fucopyranosyl]-quillaic\;acid\;-3-O-[{\beta}-D-galactopyranosyl(1{\rightarrow}2)]-6-O-n-butyl\;ester-{\beta}-D-glucuronopyranoside$, respectively.

• Journal of the Korean Crystal Growth and Crystal Technology
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• v.34 no.2
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• pp.55-60
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• 2024

Two-dimensional (2D) RuO₂ nanosheets with nanometer thickness were synthesized using a chemical exfoliation method. The synthesized 2D-RuO₂ was hybridized with Ag-nanowire (NW), which is attracting attention as a next-generation transparent electrode material. After coating Ag-NW on the substrate, 2D-RuO₂ was subsequently coated on the Ag-NW. Although there was a decrease in optical transmittance, the hybridization of 2D-RuO₂ confirmed the effect of reducing sheet resistance. Furthermore, the flexibility of the fabricated transparent electrodes was also studied. It was confirmed by the change in sheet resistance after bending. The additional coating of 2D-RuO₂ improved the flexibility of the transparent electrodes.

• Korean Journal of Mineralogy and Petrology
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• v.34 no.2
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• pp.107-120
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• 2021

The Komdok Pb-Zn deposit, which is the largest Pb-Zn deposit in Korea, is located at the Hyesan-Riwon metallogenic zone in Jiao Liao Ji belt included Paleoproterozoic Macheolryeong group. The geology of this deposit consists of Paleoproterozoic metasedimentary rocks, Jurassic Mantapsan intrusive rocks and Cenozoic basalt. The Komdok deposit which is a SEDEX type deposit occurs as layer ore and vein ore in the Paleoproterozoic metasedimentary rocks. Based on mineral petrography and paragenesis, dolomites from this deposit are classified four types (1. dolomite (D₀) as hostrock, 2. early dolomite (D₁) associated with tremolite, actinolite, diopside, sphalerite and galena from amphibolite facies, 3. late dolomite (D₂) associated with talc, calcite, quartz, sphalerite and galena from amphibolite facies, 4. dolomite (D₃) associated with white mica, chlorite, sphalerite and galena from quartz vein). The structural formulars of dolomites are determined to be Ca_1.00-1.20Mg_0.80-0.99Fe_0.00-0.01Zn_0.00-0.02(CO₃)₂(D₀), Ca_1.00-1.02M_0.97-0.99Fe_0.00-0.01Zn_0.00-0.02(CO₃)₂(D₁), Ca_0.99-1.03Mg_0.93-0.98Fe_0.01-0.05Mn_0.00-0.01As_0.00-0.01(CO₃)₂(D₂) and Ca_0.95-1.04Mg_0.59-0.68Fe_0.30-0.36Mn_0.00-0.01 (CO₃)₂(D₃), respectively. It means that dolomites from Komdok deposit have higher content of trace elements (FeO, MnO, HfO₂, ZnO, PbO, Sb₂O₅ and As₂O₅) compared to the theoretical composition of dolomite. These trace elements (FeO, MnO, ZnO, Sb₂O₅ and As₂O₅) show increase and decrease trend according to paragenetic sequence, but HfO₂ and PbO elements no show increase and decrease trend according to paragenetic sequence. Dolomites correspond to Ferroan dolomite (D₀, D₁ and D₂), and Ferroan dolomite and ankerite (D₃), respectively. Therefore, 1) dolomite (D₀) as hostrock was formed by subsequent diagenesis after sedimentation of Paleoproterozoic (2012~1700 Ma) silica-bearing dolomite in the marine evaporative environment. 2) Early dolomite (D₁) was formed by hydrothermal metasomatism origined metamorphism (amphibolite facies) associated with intrusion (1890~1680 Ma) of Paleoproterozoic Riwon complex. 3) Late dolomte (D₂) was formed from residual fluid by a decrease of temperature and pressure. and dolomite (D₃) in quartz vein was formed by intrusion (213~181 Ma) of Jurassic Mantapsan intrusive rocks.