• Bulletin of the Korean Chemical Society
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• 제25권11호
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• pp.1661-1666
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• 2004

The reaction of titanium tetraisopropoxide with 2 equiv of N,N-diethyl acetoacetamide affords Ti($O^iPr)_2(CH_3COCHCONEt_2)_2$ (1) as colorless crystals in 80% yield. Compound 1 is characterized by spectroscopic (Mass and $^1H/^{13}C$ NMR) and microanalytical data. Molecular structure of 1 has been determined by a single crystal X-ray diffraction study, which reveals that it is a monomeric, cis-diisopropoxide and contains a six coordinate Ti(IV) atom with a cis($CONEt_2$), trans($COCH_3$) configuration (1a) in a distorted octahedral environment. Variable-temperature $^1H$ NMR spectra of 1 indicate that it exists as an equilibrium mixture of cis, trans (1a) and cis, cis (1b) isomers in a 0.57 : 0.43 ratio at -20$^{\circ}C$ in toluene-$d_8$ solution. Thermal properties of 1 as a MOCVD precursor for titanium dioxide films have been evaluated by thermal gravimetric analysis and vapor pressure measurement. Thin films of pure anatase titanium dioxide (after annealing above 500$^{\circ}C$ under oxygen) have been grown on Si(100) with precursor 1 in the substrate temperature range of 350- 500$^{\circ}$ using a bubbler-based MOCVD method.

• Bulletin of the Korean Chemical Society
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• 제33권9호
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• pp.2985-2990
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• 2012

New thiazoline derivatives 7a-c, and thiophenes 9a-c linked to indole moiety were easily prepared via the reaction of the acrylamide derivative 3 with phenacyl bromides 4a-c, depending on the reaction conditions. In addition, the reaction of compound 3 with hydrazonoyl chlorides 11a-f afforded a series of 1,3,4-thiadiazole derivatives 13a-f. Moreover, coupling of 3-(3-methyl-1H-indol-2-yl)-3-oxopropanenitrile (2) with the diazonium salts of 3-phenyl-5-aminopyrazole 16 or 3-amino-1,2,4-triazole 17 gave the corresponding hydrazones 18 and 19, respectively. Cyclization of the latter hydrazones yielded the corresponding pyrazolo[5,1-c]-1,2,4-triazine and 1,2,4-triazolo[5,1-c]-1,2,4-triazine derivatives 20 and 21, respectively. The structures of the synthesized compounds were assigned on the basis of elemental analysis, IR, $^1H$ NMR and mass spectral data. All the synthesized compounds were tested for in vitro activities against certain strains of fungi such as Aspergillus niger, Aspergillus nodulans, Alternaria alternate. Compounds showed marked inhibition of fungal growth nearly equal to the standards.

• Applied Biological Chemistry
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• 제50권3호
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• pp.233-237
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• 2007

순무 뿌리로부터 활성 물질을 분리 동정 하기 위하여 80% MeOH 수용액으로 추출하고 이를 여과, 감압 농축하여 MeOH 추출물을 얻었다. 이를 EtOAc분획, n-BuOH분획, $H_{2}O$분획으로 나누었으며, EtOAc분획과 n-BuOH분획에 대해 silica gel 및 ODS column chromatography를 실시하여 5종의 화합물을 분리 정제하였다. $^{1}H-NMR$, $^{13}C-NMR$, DEPT spectrum 및 Mass spectrum 등을 통하여 palmitic acid methyl ester(1), linolenic acid methyl ester(2), linoleic acid methyl ester(3), ${\beta}-sitosterol$(4), daucosterol(5)으로 구조를 결정하였다.

• Journal of Plant Biotechnology
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• 제36권1호
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• pp.64-67
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• 2009

순무 뿌리로부터 활성 물질을 분리 동정하기 위하여 80% MeOH 수용액으로 추출하고 이를 여과, 감압 농축하여 MeOH 추출물을 얻었다. 이를 EtOAc 분획, n-BuOH 분획, $H_2O$ 분획으로 나누었으며, EtOAc분획과 n-BuOH 분획에 대해 silica gel 및 ODS column chromatography를 실시하여 4종의 이차대사산물을 분리 정제하였다. $^1H-NMR,\;^{13}C-NMR$, DEPT spectrum 및 mass spectrum등을 통하여 4- (methoxymethyl)phonol(1), ${\alpha}$- methoxy-2, 5- furandimethanel (2), phenyl-${\beta}$-glucopyranoside(3) 및 2-phenylethyl-${\beta}$-D -glucopyranoside (4)로 구조를 결정하였다. 이 화합물들은 순무에서는 처음 분리되었다.

• Archives of Pharmacal Research
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• 제19권2호
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• pp.153-159
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• 1996

A new streptothricin family antibiotic producing Streptomyces spp. SNUS 8810-111 was isolated from a soil sample. Study of its morphological and physiological characters indicated that the antibiotic producing organism was a Streptomyces spp. Taxonomical studies suggested that the organism might belong to the genus streptomyces gougeroti. The organism produced antibiotics most in calcium carbonate-tryptic soy broth. The active principles were recovered from the broth with a cation exchange resin and eluted from the resin with HCI. Cellulose column chromatography gave two active principles.$^1H-^1H$ Homo-COSY study on the first compound revealed four structural components. Total hydrolysis of the antibiotic with HCI allowed isolation of $\beta-lysine$. From these data the antibiotic was found to be streptothricin D. The other compound showed one additional signal in the .$^1H$NMR and the $^{13}C$ NMR spectra. The signal was from a methyl group attached to a nitrogen atom. Comparison of the NMR signals with those of streptothricin D suggested that the compound was N-methyl-streptothricin D which was a new compound in the family of streptothricin antibiotics.

• Applied Biological Chemistry
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• 제47권2호
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• pp.164-169
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• 2004

감자더뎅이병 방제용 생물제제(biocontrol agenL BCA)를 개발하기 위하여 국내 토양으로부터 분리된 5,000여 방선균 균주를 대상으로 더뎅이병 관련 병원균(Streptomyces scabiei및 S. turgidiscabies)에 대한 in vitro또는 in vivo 활성검정을 실시하였다. 활성검정 결과 길항력이 우수한 균주로서 9균주가 선발되었으며 실제 재배포장에서 사용되고 있는 dazomet및 mancozeb 등 농약에 대한 감수성 시험을 실시하여 A020645 균주가 길항활성 뿐만 아니라 약제저항성이 가장 높음을 확인하고 더뎅이병 방제용 BCA 균주로 선발하였다. 본 균주로부터 항균활성물질을 분리하기 위하여 액체배양액으로부터 음이온교환 크로마토그래피(anion exchange chromatography), solidphase(ODS) extraction, TLC, 역상 HPLC 등을 실시하여 최종적으로 compound A와 B를 순수 분리하였다. Compound A와 B는 NMR 분석 결과 nucleoside계 화합물로 판단된다.

• 한국자원식물학회지
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• 제31권1호
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• pp.1-9
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• 2018

제주모시풀에서 각종 column chromatography법을 이용하여 2종의 flavonoid를 분리하여, $^1H$-, $^{13}C-NMR$, LC ESI-IT-TOF MS를 통해 구조동정 할 수 있었다. 분리된 물질이 심장세포에서 높은 항산화 활성을 가지고 있으며, 활성 산소종의 작용기전 연구 및 심근경색 질환의 예방과 치료에 효과적으로 사용할 수 있는 기초자료가 될 것으로 사료된다.

• Natural Product Sciences
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• 제28권1호
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• pp.1-5
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• 2022

Two 2H-1-benzopyran derivatives, methyl 8-hydroxy-2,2-dimethyl-2H-1-benzopyran-5-carboxylate (1) and methyl 8-hydroxy-2,2-dimethyl-2H-1-benzopyran-6-carboxylate (2), including a new compound (1) were isolated from the twigs of Chaenomeles sinensis. Their chemical structures were characterized based on analysis of NMR data including ¹H and ¹³C, COSY, HSQC, and HMBC and HRMS data. The isolated compounds (1 and 2) were assessed for their anti-neuroinflammatory activity by measuring inhibition levels of nitric oxide (NO) production in lipopolysaccharide (LPS)-activated BV-2 cells and for their neurotrophic activity by the secretion of nerve growth factor (NGF) in C6 cells. Compounds 1 and 2 exhibited powerful anti-neuroinflammatory effects with IC₅₀ values of 17.14 and 19.30 μM, respectively, without cell toxicity, and also showed moderate effects on the stimulation of NGF secretion levels with 113.15 ± 3.54 and 130.20 ± 8.03%, respectively. The biosynthetic pathway of 1 and 2 was proposed that they would be derived from a protocatechuic acid and an isoprenyl unit.

• 한국한의학연구원논문집
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• 제13권3호
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• pp.157-163
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• 2007

Objective: Polygonum multiflorum Thunberg (Polygonaceae) has been traditionally used as a tonic and the purgative in China and Korea. The genus Polygonum is a source of a wide range of phenolic compound, flavanoids, anthraquinones, stilbenes and tannins. In this study, three anthraquinones were isolated and quantitative determination of anthraquinones from P multiflorum has been developed for quality standardization. Methods : Three anthraquinone derivatives were isolated from a methanol extract of the radix of P. multiflorum by the chromatographic separation. Their structures were identified as emodin, physcion and ${\omega}$-hydroxyemodin on the basis of spectral data (MS, lH-NMR, 13C-NMR) and chemical analysis. HPLC analysis was performed to determine the contents of emodin, physcion, chrysophanol, rhein and ${\omega}$-hydroxyemodin in P. multiflorum from different specimens were collected from twenty Korean markets. Results: According to the results, the contents of emodin, physcion, chrysophanol, rhein and ${\omega}$-hydroxyemodin were 0.145%, 0.434%, 0.016%, 0.026%, 0.030% by HPLC, respectively. Conclusions : In these results, we have determined the contents of emodin, physcion, chrysophanol, rhein and ${\omega}$-hydroxyemodin in P. multiflorum, respectively. We hope that this study will contribute to the standardization and quality control of herbal medicine.

• Natural Product Sciences
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• 제10권5호
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• pp.207-210
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• 2004

Three chalcones and a stilbenoid have been isolated from the stem bark of Lindera erythrocarpa. They were elucidated as 2'-hydroxy-3',4',5',6'- tetramethoxychalcone, 2',4'-dihydroxy-3',6'-dimethoxy chalcone, 2',4',5',6'- tetrahydroxy-3'-methoxychalcone, and 5,6-dihydroxy-2,3,4-trimethoxystilbene. Chemical structures were elucidated on the basis of MS, $^1H,\;^{13}C$ and 2D-NMR spectroscopic data. This is the first report on the isolation of these compounds from the L. erythrocarpa.