• Archives of Pharmacal Research
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• 제19권6호
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• pp.551-553
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• 1996

A genuine dammarane glycoside, named ginsenoside $Rg_{5}$, has been isolated by repeated column chromatography and preparative HPLC from the MeOH extract of Korean red ginseng (Panax ginseng C.A. Meyer). The chemical structure of ginsenoside$ Rg_{5}$ was determined as $3-O-[{\beta}-D-glucopyranosyl (1{\rightarrow}2)-{\beta}-D-glucopyranosyl]$ dammar-20(22), $24-diene-3{\beta},12{\beta}-diol$ by spectral and chemical methods. The stereostructure of a double bond at C-20(22) of ginsenoside $Rg_{5}$ was characterized as (E) from the chemical shift of C-21 in the $^{13}C-NMR $and a NOESY experiment in the $^{1}H-NMR$.

• Archives of Pharmacal Research
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• 제17권1호
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• pp.48-50
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• 1994

Three p-coumaroylamino acids (p-CAAs) were isolated from the yeast-elicited Ephedra distachya cultures by consecutive purification using XAD_2, silicagel and RP-HPLC. Retention times on HPLC as well as their UV, IR, NMR and MS spectral data indicated that the yeast-induced p-CAAs wre p-coumaroyl--D-valine, p-coumaroyl-D-serine and p-coumarouyl-D-threonine, respectively. The structures of p-CAAs were confirmed by the comparison of their physico-chemical properties 3with those of synthetic ones. They were isolated and identified for the first time from natural products and supposed to be accumulated as phytoalexins of Ephedra.

• 한국식생활문화학회지
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• 제5권2호
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• pp.243-251
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• 1990

두릅나무 순의 saponin을 추출하여 그 구조를 밝혀 본 결과는 다음과 같다. 1. 자연산 날 것 식용적기의 crude saponin에서 aglycon으로 oleanolic acid와 hederagenin외에 1,3-methylenedioxy-3-dehydroxyoleanolic acid를 동정하였으며 당으로 ${\alpha},\;{\beta}-glucose$와 arabinose, rhamnose를 확인하였다. 2. 자연산 날 것 식용적기에 가장 많은 ‘b’ saponin(elatoside $Fh_2$)을 분리하여 동정한 결과 그 구조는 3-0-$[{\alpha}-L-arabinopyranosyl(1{\rightarrow}2)-{\beta}-D-glucopyranosyl]$-28-O-${\beta}-D-glucopyranosyl$ oleanolic acid라 추정된다.

• Natural Product Sciences
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• 제19권4호
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• pp.355-359
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• 2013

A new monoterpene, crocusatin M (1), was isolated from the flower buds of Buddleja officinalis, together with four known monoterpenes, (6R)-hydroxy-1,1,5-trimethylcyclohex-4-enone (2), (+)-dehydrovomifoliol (3), 7-epiloliolide (4), and crocusatin D (5). Their structures were determined by an extensive analysis of 1D, 2D NMR, HRESI-MS, and CD data as well as by comparison of their spectroscopic data with those of literatures. All isolates were evaluated for inhibitory activities on LPS-induced nitric oxide production in RAW 264.7 cells. Among them, compounds 2 and 3 showed moderate inhibitory effects with $IC_{50}$ values of 63.8 and 24.4 ${\mu}g/ml$, respectively.

• Journal of Applied Biological Chemistry
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• 제49권1호
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• pp.21-23
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• 2006

As part of a program to discover bioactive natural products from marine organisms, two new enantiomers, ent-3,6-Epidioxy-4,6,8,10-tetraethyltetradeca-7,11-dienoic acid and ent-[3,5-Diethyl-5-(2-ethyl-hex-3-enyl)-5H-furan-2-ylidene]-acetic acid methyl ether, were isolated from a sponge Plakortis sp. These compounds showed strong in vitro antiproliferative effects on promastigotes of Leishmania mexicania, flagellate protozoan that causes leishmaniasis. Structures were assumed by interpretation of NMR spectroscopic data and optical rotation. Both compounds exhibited significant antileishmanial activities in vitro with $IC_{50}$ of 1.0-23.0 ${\mu}g/ml$.

• 한국추진공학회지
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• 제19권3호
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• pp.96-102
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• 2015

기존에 사용되고 있는 대부분의 추진물질들은 연소 시 이산화탄소, 염산가스 등의 환경유해 물질을 다량 발생시킨다. 본 연구에서는 이러한 문제점을 개선하기 위한 테트라진 계열의 저탄소 고질소 화합물인 DAAT의 합성공정을 확립하였다. 또한, 문헌에 빠져있는 구체적인 공정법 및 특성 분석 결과를 서술하였다. 그리고 분광분석(NMR, IR)을 통한 DAAT의 구조분석과 열, 충격, 마찰 안정성을 측정하였고, Gaussian 09와 EXPLO5를 이용하여 생성열과 폭발 특성(폭압, 폭속) 등을 계산하였다.

• Natural Product Sciences
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• 제26권2호
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• pp.144-150
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• 2020

Phytochemical investigation of leaves, barks and roots of Nauclea vanderguchtii led to the isolation of sixteen compounds, which includes one citric acid derivative (2), one alkaloid (16), one peptide derivative (3), and twelve triterpenes (1, 4 - 13). These compounds were identified as rotundanonic acid (1), 2-hydroxy-1,2,3-propanetricarboxylic acid 2-methyl ester (2), asperphenamate (3), lupeol (4), stigmasterol (5), betulin (6), betulenic acid (7), stigmasterol 3-O-β-D-glucopyranoside (8), quinovic acid 3β-O-α-L-rhamnoside (9), α-amyrin (10), 3-oxoquinovic acid (11), ursolic acid (12), hederagenin (13), rotundic acid (14), clethric acid (15), and naucleficine (16) by the analysis of their NMR spectroscopic data including 2D NMR spectra and by comparison of their spectroscopic data reported in the literature. Compounds 1 and 3 were isolated for the first time in the genus Nauclea, and compound 2 was isolated for the first time from the Rubiaceae family. Complete NMR assignations for 1 have been published for the first time.

• Bulletin of the Korean Chemical Society
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• 제19권1호
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• pp.68-74
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• 1998

The complexation of ethylammonium ion by alkyl p-tert-butylcalix[6]aryl ester derivatives was studied via measurements of proton and carbon spin-lattice relaxation times $(T_1)$ and chemical shift changes in solution state $(CDCl_3)$. The results indicate that the endo-type complexes are formed and that the overall tumbling rates of these complexes are more rapid than those of the corresponding free hosts. The association constants for these complexes in $THF-d_8$ were determined by $^1H$ NMR titration at several different temperatures to estimate the relevant thermodynamic parameters. The logK's for ethylammonium complexes of methyl, ethyl, and propyl esters at 313 K, for example, were found to be 1.56, 3.41, and 3.08, respectively. The complexes formed may be thought of as being kinetically stable in view of their $^1H$ NMR behavior in 2 : 1 host/guest solution.

• Journal of the Korean Wood Science and Technology
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• 제34권3호
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• pp.73-83
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• 2006

구상나무(Abies koreana Maximowicz)와 전나무(Abies holophylla Wilson) 잎을 채취하여 건조시킨 후 분말로 제조하여 각각 1.5 kg을 아세톤-물(7:3, v/v)로 추출하고 헥산, 메틸렌클로라이드, 에틸아세테이트 및 수용성으로 분획하여 동결건조 시켰다. 에틸아세테이트용성 분획을 Sephadex LH-20으로 충진한 칼럼에서 메탄올과 에탄올-헥산 혼합액을 용리용매로 사용하여 칼럼크로마토그래피를 실시하였다. 단리된 화합물들은 TLC로 확인한 후 $^1H-$, $^{13}C-NMR$, COSY, HETCOR 등의 스펙트럼을 사용하여 정확한 구조를 규명하였고 FAB 및 EI-MS로써 분자량을 측정하였다. 많은 양의 aromadendrin-7-O-${\beta}$-D-glucopyranoside (화합물 III), polydatin (화합물 VI), (-)-rhododendrol-2-O-${\beta}$-D-glucopyranoside (화합물 VII)가 단리되었으며, 소량의 (+)-catechin (화합물 I), kaempferol-3-O-${\beta}$-D-glucopyranoside (화합물IV), myricetin-3-O-${\beta}$-D-glucopyranoside (화합물 V), naringenin-7-O-${\beta}$-D-glucopyranoside (화합물 II)도 단리 되었다. DPPH 라디칼 소거법을 이용하여 단리된 화합물들에 대한 항산화 활성시험을 실시하였으며 (+)- catechin과 polydatin이 항산화 효능을 나타내었다.

• 한국연초학회지
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• 제24권2호
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• pp.94-100
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• 2002

Cyclodextrin glucanotransferase from Bacillus stearothemophilus and Bacillus macerans synthesized maltol and ethyl maltol monoglucoside, with a series of its maltooligo-glucosides by transglycosylation with dextrin as a donor, and maltol or ethyl maltol as an acceptor. The monoglucoside formed from reaction mixture of maltol or ethyl maltol by the successive actions of Bacillus stearothemophilus cyclodextrin glucanotransferase and Rhizopus glucoamylase was isolated by Diaion HP-20 column and silica gel column chromatography. The structure of the isolated monoglucoside was identified as maltol-$\alpha$-D-glucoside and ethyl maltol-$\alpha$-D-glucoside, respectively, by FAB-MS, UV, $^1$H-NMR, $^{13}$ C-NMR spectra and products by hydrolysis with acid, $\alpha$ - and $\beta$ -glucosidases.