• 대한화학회지
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• 제23권1호
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• pp.46-51
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• 1979

Silver triflate와 syn-collidine 존재하에서 3,4,6-tri-O-acetyl-2-phthalimido-${\beta}$-D-glucopyranosyl bromide (2)와 1,2;3,4-di-O-isopropylidene-${\alpha}$-D-galactopyranose (3)를 반응시켜 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)를 $86{\%}$의 수득률로 얻었다. 화합물 4를 hydrazine과 작용시켜 phthalimido기와 acetyl기를 동시에 제거한후, 다시 acetyl화하고 isopropylidene기와 O-acetyl기를 가수분해하면 6-O-(2-acetamido-2-deoxy-${\beta}$-D-glucopyranosyl)-D-galactopyranose (1)가 총수득율 $65.8{\%}$로 얻어졌다. 또한 화합물 4를 변형시켜 특정위치에 hydroxyl기를 가진 몇 가지 유도체도 합성하였다.

• Biomolecules & Therapeutics
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• 제9권4호
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• pp.285-290
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• 2001

Bioequivalence of two acetyl-1-carnitine tablets, test product (Carnitile tablet: Hanmi Pharm. Co., Ltd.) and reference product (Nicetil $e^{R}$ tablet: Dong-A Pharm. Co., Ltd.), was evaluated according to the guide- lines of Korea Food and Drug Administration (KFDA). Twenty-six healthy volunteers were divided randomly into two groups and administered the drug orally at the dose of 500 mg as acetyl-1-carnitine in a 2$\times$2 crossover study. Blood samples were taken at predetermined time intervals for 12 hours and the plasma concentration of acetyl-1-carnitine was determined using HPLC by derivatization with p-bromophenacyl bromide. The pearmacokinetic parameters (AU $C_{0-}$12h/ $C_{max}$ and $T_{max}$) were calculated and ANOVA was utilized for the statistical analysis of parameters. The apparent differences of these parameters between two drugs were less than 20% (i.e., 1.26,-5.08 and 8.59% for AU $C_{0-}$12h/ $C_{max}$ and $T_{max}$, respectively). The powers (1-$\beta$) for AU $C_{0-}$12h/ $C_{max}$ and $T_{max}$, and Tmax were over 0.9. Minimal detectable difference ($\Delta$) at $\alpha$=0.05, 1-$\beta$=0.8 were less than 20% (i.e.,7.31, 14.88 and 11.77% for AU $C_{0-}$12h/ $C_{max}$ and $T_{max}$, respectively). The confidence intervals ($\delta$) for these parameters were also within $\pm$ 20% (i.e.,-3.03$\leq$$\delta$$\leq$5.54, -13.80$\leq$$\delta$$\leq$3.64 and 1.69$\leq$$\delta$$\leq$15.48 for AU $C_{0-}$12h/ $C_{max}$ and $T_{max}$, respectively). These results satisfied the criteria of KFDA guideline for bioequivalence, indicating Carnitile bioequivalent to Nicetil $e^{R}$ .TEX>$^{R}$ .> R/ . R/ .

• 약학회지
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• 제27권2호
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• pp.181-184
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• 1983

DMSO-oxalyl chloride at low temperature in methylene chloride reacted with isolated secondary hydroxyl groups in some monosaccharides to give alkoxysulfonium salts, convertible to carbonyls in high yields upon addition of triethylamine. And 1, 2:5, 6-di-O-isopropylidene-.alpha.- D-allofuranose which is the key intermediate in the synthesis of 3-O-acetyl-5-O-benzoyl- 2-deoxy-2- fluoro-D-arabinofuranosyl bromide, was also obtained by oxidizing 1, 2:5, 6-di-O-isopropylidene-.alpha.- D-glucofuranose with the oxidizing reagent, followed by reduction with sodium borohydride.

• Asian-Australasian Journal of Animal Sciences
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• 제32권11호
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• pp.1686-1694
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• 2019

Objective: Lignin plays a relevant role in the inhibition of cell wall (CW) structural carbohydrate degradation. Thus, obtaining accurate estimates of the lignin content in tropical plants is important in order to properly characterize the mechanism of lignin action on CW degradation. Comparing conflicting results between the different methods available for commercial use will bring insight on the subject. This way, providing data to better understand the relationship between lignin concentration and implications with tropical forage degradation. Methods: Five grass species, Brachiaria brizantha cv $Marand{\acute{u}}$, Brachiaria brizantha cv $Xara{\acute{e}}s$(MG-5), Panicum maximum cv Mombaça, Pennisetum purpureum cv Cameroon, and Pennisetum purpureum cv Napier, were harvested at five maturity stages. Acid detergent lignin (ADL), Klason lignin (KL), acetyl bromide lignin (ABL), and permanganate lignin (PerL) were measured on all species. Lignin concentration was correlated with in vitro degradability. Results: Highly significant effects for maturity, lignin method and their interaction on lignin content were observed. The ADL, KL and ABL methods had similar negative correlations with degradability. The PerL method failed to reliably estimate the degradability of tropical grasses, possibly due to interference of other substances potentially soluble in the $KMnO_4$ solution. Conclusion: ADL and KL methods use strong acid ($H_2SO_4$) and require determination of ash and N content in the lignin residues, therefore, increasing time and cost of analysis. The ABL method has no need for such corrections and is a fast and a convenient method for determination of total lignin content in plants, thus, it may be a good option for routine laboratory analysis.

• 약학회지
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• 제48권2호
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• pp.117-121
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• 2004

Ranunculin, a potent cytotoxic component of P. koreana, was synthesized by reacting (s)-(-)-5-(hydroxymethyl)-2(5H)-furanone with 2,3,4,6-tetra-O-acetyl-$\alpha$-D-glucopyranosyl bromide and successive removal of the acetyl protecting group by 0.5 M HCl/MeOH. A new deacetylation process of the intermediate tetraacetylranunculin was deviced giving a yield of 83% of ranunculin. Protoanemonin, the cytotoxic structural moiety of ranunculin, was synthesized by dehydration of (s)-(-)-5-hydroxymethyl-2(5H)-furanone. Ranunculin showed a moderate cytototoxic activity against A-549 (ED$_{50}$=7.53 $\mu\textrm{g}$/$m\ell$), NIH3T (ED$_{50}$=13.6$\mu\textrm{g}$/$m\ell$), and SK-OV-3 (ED$_{50}$=17.5 $\mu\textrm{g}$/$m\ell$). Meanwhile, protoanemonin also exhibited moderate cytotoxicity against A-549 (ED$_{50}$=9.38 $\mu\textrm{g}$/$m\ell$), NIH3T (ED$_{50}$=13.8 $\mu\textrm{g}$/$m\ell$), and SK-OV-3 (ED$_{50}$=15.1 $\mu\textrm{g}$/$m\ell$). It was found that both of the synthetic products showed a potenter cytotoxicity against A-549.ainst A-549.

• 한국치위생학회지
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• 제21권5호
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• pp.545-553
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• 2021

Objectives: This study aimed to investigate the cytotoxicity of Nexus RMGIC, an indirect restorative cement, on cell survival rate and reactive oxygen species (ROS) production in periodontal stem cells (PDSCs). Methods: PDSCs were incubated with serially diluted Nexus RMGIC eluates with and without the addition of N-acetyl-cysteine (NAC). Cell survival was determined using the 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay. The ROS generation was determined by measuring the fluorescence intensity for 2',7'-dichlorofluorescin diacetate. Results: Nexus RMGIC exposure decreased cell proliferation and cell survival rate in a dose-dependent manner (1:8, 1:4, 1:2, 1:1) in PDSCs. The cytotoxicity of Nexus RMGIC was inhibited by treatment with 10-mM NAC. In addition, the production of ROS was detected by immunofluorescence after PDSCs were exposed to Nexus RMGIC. However, ROS generation was significantly suppressed in the NAC pretreatment compared with the Nexus RMGIC group. Conclusions: Nexus RMGIC increased the cytotoxicity and ROS generation. ROS was involved in Nexus RMGIC-induced cell toxicity.

• 공업화학
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• 제2권3호
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• pp.229-237
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• 1991

합성촉매로 triethylamine(TEA), triethylbenzyl ammonium chloride(TEBAC), cetyltrimethyl ammonium bromide(CTMAB) 등의 아민 및 chromium acetyl acetate(CAA), triphenylantimony(TPA) 등의 유기금속화합물을 사용하여 합성촉매가 비닐에스테르수지의 합성 및 물성에 미치는 영향을 연구하였다. 반응성, 경화시간, 저장안정성 등을 고려해 볼 때, 촉매의 적절한 사용량은 methacrylic acid(MAA)에 대하여 아민계의 경우에는 1.7~2.2%(중량 %), 유기금속계의 경우에는 2.5~3.1%(중량 %)였다. 촉매의 반응성은 TEA>TEBAC>CT-MAB>CAA>TPA의 순이었으며, 촉매의 온도의존성은 $110^{\circ}C$ 이상에서 크게 나타났다. 수지의 저장안정성은 합성 후 TPA를 MAA에 대하여 2.0% (중량 %) 이내의 범위에서 첨가하였을 때, 경화시간의 지연됨이 없이 개량되었다.

• 약학회지
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• 제40권2호
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• pp.163-169
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• 1996

Glycosidation of 20(S)-protopanaxadiol obtained by the alkaline hydrolysis of total ginsenosides with 2,3,4,6-tetra-O-acetyl-${\alpha$-D-glucopyranosyl bromide in the presence of $CdCO_3$ in benzene-dioxane gave a mixture of acetylated monoglucosides and diglucosides in a total yield of 68%. Under the same condenstion condition, 20-dehydroxyglucosides were formed by dehydration of 12-O-glucosides. The structures of produced glycosides were elucidated as 3-O-${\beta$-D-glucopyranosyl-20(S)-protopanaxadiol, 12-O-${\beta$-D-glucopyranosyl-dammar-20(22), 24-dien-$3{\beta},12{\beta}$-diol, 3,12-di-O-${\beta}$-D-glucopyranosyl-dammar-20(22), 24-dien-$3{\beta},\;12{\beta}$-diol, respectively.

• 약학회지
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• 제38권4호
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• pp.425-429
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• 1994

The genuine aglycone, 20(S)-protopanaxadiol, obtained from the leaves of Panax ginseng as a result of direct alkaline treatment was isolated and characterized by spectroscopic evidences. The study on the yield of genuine aglycone which is produced from the treatment of some kinds of alkali was carried out. $Ginsenoside-Rh_2$ was synthesized by conjugation of 2,3,4,6-tetra-O-acetyl-${\alpha}$-D-glucopyranosyl bromide to 20(S)-protopanaxadiol in the presence of silver carbonate and cadmium cabonate. The preparation of $ginsenoside-Rh_2$ by this method is a new one which the yield of this saponin can be improved in the mild condition.

• Journal of the Korean Wood Science and Technology
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• 제14권4호
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• pp.14-20
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• 1986

지리산(智異山)의 10종(種) 활엽수재에 대(對)한 AcBr(acetyl bromide) lignin의 UV spectrum을 조사(調査)한바 그 결과(結果)을 요약(要約)하면 다음과 같다. 1. 각수종(各樹種) 모두 spectrum curve의 최대정점(最大頂點)은 249nm에, 최소(最少) 정점(頂點)은 262-266nm에, 또 중간정점(中間頂點)은 270-280nm에 있었으며, Bj$\ddot{o}$rkman lignin이나 lignin sulfonic acid 등의 UV spectrum상(上)에서 볼수 있는 견(Shoulder)은 본(本) 연구(硏究)의 활엽수재 AcBr lignin의 spectrum에서는 볼수 없었다. 2. 10개(個) 수종(樹種) 각(各) 정점(頂點)의 평균흡광도(平均吸光度)는 249nm에서 0.457${\pm}$0.0077, 262-266nm에서 0.297${\pm}$0.0029, 280nm에서 0.309${\pm}$0.0067이었다. 3. 10개(個) 수종(樹種) 각(各) 정점(頂點)의 평균흡광계수(平均吸光係數)는 249nm에서 25.005${\pm}$0.3825, 262-266nm에서 16.264${\pm}$0.2347, 280nm에서 16.863${\pm}$0.3444였다. 4. 리그닌의 정량(定量)을 위(爲)한 270-280nm에서의 각(各) 수종별(樹種別) 리그닌의 흡광계수(吸光係數)는 다음과 같았다. 좁은잎단풍나무재(材) 16.939${\pm}$0.3735, 서어나무재(材) 17.411${\pm}$0.2937, 층층나무재(材) 16.579${\pm}$0.4348, 물푸레나무재(材) 16.385${\pm}$0.4140, 나도밤나무재(材) 16.287${\pm}$0.4156, 굴피나무재(材) 16.492${\pm}$0.1432, 산벗나무재(材) 16.343${\pm}$0.3177, 회화나무재(材) 17.549${\pm}$0.3253, 노각나무재(材) 18.400${\pm}$0.2925, 쪽동백 16.245${\pm}$0.4339였다. 5. 270-280nm에서 완만한 흡광도(吸光度) 정점(頂點)을 나타내는 것6으로 보아 본(本) 리그닌은 guaiacyl-syringyl lignin인 것으로 사료(思料)된다.