• Journal of the Korean Chemical Society
• /
• v.40 no.8
• /
• pp.565-570
• /
• 1996

A simple and efficient new synthetic method of 4'-[N-(9-acridinyl)]-1'-(N-methanesulfonyl)-3'-methoxyquinonediimide(AMQD, 5) was developed and six new nucleophilic adducts(6a-6f) were prepared by the addition of thiophenol derivatives to AMQD. The structures of these compounds were confirmed by elemental analysis, mass, ir and nmr spectra.

• Journal of Biosystems Engineering
• /
• v.20 no.3
• /
• pp.299-306
• /
• 1995

This study was carried to find out relationships between water content and sugar content in fruit and vegetables and present the possibility of estimating sugar content by measuring water content. Water content and sugar content of melons, peaches, and apples were measured. Both F-test and linear regression analysis on the experimental data were done. The regression models were developed and validated. The results were summarized as follow : 1. According to the F-test, the coefficients of determinant were greater than 0.8, and significance probability was less than 0.0001 in each materials. 2. According to the regression analysis of melons, peaches, and apples, the standard errors of calibration(SEC) were 0.67 brix%, 0.82 brix%, and 0.72 brix%, respectively. 3. The standard errors of prediction(SEP) were 0.76 brix%, 1.03 brix%, and 0.77 brix%, respectively. 4. The relationship between sugar content and water content in apple was successfully applied to measure the sugar content from hydrogen NMR spectrum of apple samples.

• Natural Product Sciences
• /
• v.24 no.1
• /
• pp.54-58
• /
• 2018

A phytochemical investigation of Allium macrostemon Bunge (Liliaceae) afforded the new pregnane steroidal glycoside, named allimacroside F (1), along with three known glycosides, benzyl-O-${\alpha}-{\text\tiny{L}}$-rhamnopyranosyl-($1{\rightarrow}6$)-${\beta}-{\text\tiny{D}}$-glucopyranoside (2), phenylethyl-O-${\alpha}-{\text\tiny{L}}$-rhamnopyranosyl-($1{\rightarrow}6$)-${\beta}-{\text\tiny{D}}$-glucopyranoside (3), (Z)-3-hexenyl-O-${\alpha}-{\text\tiny{L}}$-rhamnopyranosyl-($1{\rightarrow}6$)-${\beta}-{\text\tiny{D}}$-glucopyranoside (4). The identification and structural elucidation of a new compound (1) was carried out based on spectral data analyses ($^1H-NMR$, $^{13}C-NMR$, $^1H-^1H$ COSY, HSQC, HMBC, and NOESY) and HR-FAB-MS.

• YAKHAK HOEJI
• /
• v.43 no.3
• /
• pp.294-299
• /
• 1999

From the water fraction of the MeOH extract, three compounds, 1,3,4,5-terrahydroxycyclo-hexanecarboxylic acid 3-(3,4-dihydroxycinnamate) (chlorogenic acid), $quercetin 3-O-{\beta}-D-galactopyranoside(hyperoside)$, and 1 (R)-hydroxy-3,4-seco-lup-4(23), 20(30)-dien-3,$11{\alpha}-olactone-{\alpha}-L-rhamnopyrnaosy(1{\rightarrow}4)-{\beta}-D-glucopyanosy(1{\rightarrow}6)-{\beta}-L-glucopyrnaosyl$ ester (chiisanoside) were isolated and their strutures determinated by $^1H-NMR,{\;}^{13}C-NMR$, IR, and FAB-Mass. Chlorogenic acid and Chiisanoside had been quantitated by HPLC from eight Acanthopanax species per 10 g A. koreanum 19.82, 4.17 mg, A. nambunensis 65.00, 1.86mg, A. chiisanense 27.19, 8.17mg, A. sessiliflorum 7.49, 5.88 mg.

• Journal of the Korean Wood Science and Technology
• /
• v.29 no.4
• /
• pp.97-102
• /
• 2001

EtOAc extract from the bark of Pinus koraiensis Sieb. et Zucc was isolated by column chromatography which was packed with Sephadex LH-20 or TSK-gel HW-40F. Several stilbene glycosides were identified by $^1H{\cdot}^{13}C$-NMR, HMQC, HMBC and $FAB^+$ MS. Three stilbene glycosides, Z-pinostilbenoside, E-desoxyrhaponticin, and E-resveratroloside, were identified.

• Bulletin of the Korean Chemical Society
• /
• v.33 no.7
• /
• pp.2419-2422
• /
• 2012

• Bulletin of the Korean Chemical Society
• /
• v.14 no.5
• /
• pp.588-592
• /
• 1993

The $^1H-NMR$ signals of the heme methyl, propionate and related chemical groups of cytochrome $c_3$ from Desulfovibrio vulgaris Miyazaki F (D.v. MF) were site-specifically assigned by means of 1D-NOE, 2D-DQFCOSY and 2D-TOCSY spectra. They were consistent with the site-specific assignments of the hemes with the highest and second-lowest redox potentials reported by Fan et al. (Biochemistry, 29, 2257-2263 1990). The site-specific heme assignments were also supported by NOE between the methyl groups of these hemes and the side chain of Val-18.

• Analytical Science and Technology
• /
• v.14 no.2
• /
• pp.159-166
• /
• 2001

A humic acid(HA, Aldrich Co) sample was subjected to ultrafiltration for molecular size fractionation and three fractions of different nominal size($F_1$: 1,000-10,000 daltons; $F_2$: 10,000-50,000 daltons; $F_3$: 100,000-300,000 daltons) were obtained. The structural characteristics of the size-fractionated HA were analyzed using their IR and solid state C-13 NMR spectral data, and the carboxylate group contents of the humic acids were determined using their pH titration data. The $^7F_0-{^5}D_0$ excitation spectra of Eu(III) complexes of the size-fractionated mgHA in aqueous solution were acquired($[Eu(III)]=1.0{\times}10^{-4}mol\;L^{-1}$, $(HA)=470-970mg\;L^{-1}$) at pH 5.0 using a pulsed tunable laser system, in which metal binding properties of the size-fractionated HA were elucidated and compared on another. Characterization of the IR and C-13 NMR spectral data indicated that the fraction($F_3$) with molecules of larger size were primarily aliphatic, while the fractions($F_1$, $F_2$) with smaller molecules of less than 50,000 daltons were predominantly aromatic. Titration data were consistent with an increase in the number of carboxylate groups per unit mass as molecular size became smaller. The $^7F_0-{^5}D_0$ excitation spectral data of Eu(III)-humate complexes showed that the peak maxima on these spectra were shifted toward lower energies with increasing molecular size of HA, indicating the higher degree of bindings of the Eu in the molecules of larger size. We also discussed the relationship of the lower energy shifts of the maximum peaks with increasing the molecular size of HA with the structural differences of the size-fractionated HA.

• The Transactions of the Korean Institute of Electrical Engineers
• /
• v.41 no.5
• /
• pp.525-532
• /
• 1992

Fluorine-doped YBaS12TCuS13TOS17-xTFS1yT superconducting materials with y varing two orders of magnitude form 0.02 to 2.0 have been prepared by a sol-gel process by using metal nitrate salts, sodium hydroxide and sodium fluoride. Fluorine contents have been measured using an ion-selective electrode. All fluorine doped as reactant were found to be present in the resulted samples. From the observation of XRD it has been concluded that the samples with y 0.2 formed simply the single phase of perovskite structure, whereas those with y 0.5 yielded together some compounds such as BaFS12T, YFS13T and CuO in the resulted samples. The observation of solid state S019TF NMR has been carried out in order to check whether fluorine was actually incorporated into the lattice sites, and the experimental results revealed that the mole ratio of fluorine incorporated into the lattice sites of YBaS12TCuS13TOS17-xT was approximately 0.2 per mole of the compound. Also electrical resistivity measurement indicated that onset transition temperature has the tendency to increase slightly with increasing y in the dilute region as y 0.2.

• Bulletin of the Korean Chemical Society
• /
• v.12 no.1
• /
• pp.1-2
• /
• 1991