• Korean Journal of Microbiology
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• v.23 no.4
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• pp.241-247
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• 1985

The objectives of this study were to isolate and identify ninhydrin positive substande(s) produced in the culture broth of Pseudomonas fluorescens. It was found that the NPS could stimulate bioconversion of furfural into furoic acid. In order to isolate the NPS from the culture broth, cell free filtrate was subjected to ion-exchange chromatography, gel-permeation and finally to cellulose column chromatography. The purified NPS was white amorphous power and very soluble in water, slightly soluble in methanol and very insoluble in organic solvents. UV, and IR absorption spectra. $^H$ and $^{13}C-NMR$ were measured in order to identify the chemical structure of the NPS.

• Korean Journal of Medicinal Crop Science
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• v.12 no.3
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• pp.179-182
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• 2004

Bioassay-directed fractionation of the dried roots of Salvia miltiorrhiza led to the isolation of abietane tanshinones, cryptotanshinone and dibydrotanshinone I. Their structures were elucidated using $^1H-\;and\;^{13}C-NMR$, UV, IR and mass spectral analyses. These compounds exhibited a moderate antimicrobial activities against Staphylococcus epidemidis, Staphylococcus aureus, and Staphylococcus pyogene.

• Proceedings of the Korean Society of Soil and Groundwater Environment Conference
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• 2002.09a
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• pp.191-194
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• 2002

Humic acid, fulvic acid and humin present in volcanic ash soil were isolated by IHSS standard procedure and their characteristics were analyzed as a basic study to evaluate the effect of humic substances on the behaviour of pollutants in contaminated surface soil. The volcanic ash soil contained 42.1 % of total organic matter based on the oven-dried soil, and humin, humic and fulvic acids corresponded to 67.5 %, 15.2 %, 7.6 % of TOM respectively. Structural informations of the humic fractions were obtained from their elemental analysis and IR, CPMAS C-13 NMR spectral analysis and the differences among them are discussed with their C/H, O/C ratios and distributions of carbon types in the molecules.

• Journal of the Korean Chemical Society
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• v.51 no.6
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• pp.520-525
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• 2007

Three-component coupling of thiourea/urea, various structurally diverse aromatic aldehydes and ammonium acetate is catalyzed by activated fly ash in dry media under microwave irradiation to give 6-aryl-1,2,4,5-tetrazinan- 3-thiones/ones in good yields. The structure of 6-aryl-1,2,4,5-tetrazinan-3-thiones/ones have been elucidated on the basis of their melting points, elemental analysis, MS, IR, 1H NMR, D2O exchange, 13C NMR and two dimensional NMR spectral studies including Homonuclear Correlation (HOMOCOR) and Heteronuclear Single Quantum Correlation (HSQC) spectra.

• Journal of the Korean Wood Science and Technology
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• v.31 no.1
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• pp.16-21
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• 2003

The methanol extractives from root bark of Ulmus davidiana var japonica nakai were fractionated with n-hexane, ethyl ether, ethyl acetate and waster, the water soluble fraction was also fractionated with silicagel column chromatograhy. The chemical structure of purifided compounds were identified with UV, IR, ¹H-NMR and ¹³C-NMR spectra and the antibacterial activities also were investigated. Two different antibacterial compounds (compound A and B) were fractionated with silicagel chromatography and TLC. Compounds B was identified as a catechin rahmnoside. The both of compounds had antibacterial activity on Staphylococcus aureus and Salmonella typhimurium.

• Bulletin of the Korean Chemical Society
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• v.34 no.3
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• pp.875-883
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• 2013

Ten new derivatives of 1,3-diazabicyclo[3.1.0]hex-3-enes linked via ether linkage to chalcones were synthesized and characterized by UV, FT-IR, $^1H$ NMR and $^{13}C$ NMR spectral techniques. The spectra of all synthesized compounds, confirmed structure-photochromic behavior relationships (SPBR) both in solution or in solid state by irradiation under UV light at 254 nm. In other efforts for first time photochromic behavior of ketoaziridines has been investigated.

• Bulletin of the Korean Chemical Society
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• v.27 no.6
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• pp.893-898
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• 2006

Novel bis- and tris-crown ethers were synthesized from 1-aza and diaza-crown ethers with 2-acryloyloxy-methyl crown ethers through Michael addition. The synthesized bis- and tris-crown ethers were characterized by their elemental analyses, $^1H$-NMR, $^{13}C$-NMR, mass spectra, IR spectra, respectively. The complexation behavior of the bis- and tris-crown ethers with $Li^+$, $Na^+$, $Na^+$, $Rb^+$, $Cs^+$ was examined by $^1H$-NMR, FAB mass, and UV spectrometry.

• Preventive Nutrition and Food Science
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• v.13 no.3
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• pp.241-244
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• 2008

Methanol extracts were prepared from Z. schinifolium leaf and successively fractionated with chloroform, butanol, and water. The butanol fraction exhibited the highest antioxidative activities. Therefore the butanol fraction was purified and a chemical structure was identified by $^1H-^{13}C-NMR$ spectra, and FT-IR. The isolated antioxidative substance was identified as quercitrin.

• Bulletin of the Korean Chemical Society
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• v.20 no.3
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• pp.355-361
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• 1999

To improve the volatility and stability of lead complexes, the principle of stabilization by saturating the metal coordination sphere by intramolecular coordination through a β-diketonates with an ethereal group has was tested. Several new lead complexes with alkoxyalkyl-substituted β-diketonates, Pb(R1C(O)CHC(O)(CH2)3OR2)2(Rl=t-Bu, Me, OMe, i-Pr, R2=Me, Et), or carboxylate, Pb(OC(O)(CH2)3OEt)2, were prepared by the reaction between Pb(OAc)2 and corresponding alkoxyalkyl-substituted β-diketonates, and they were found to have a viscous liquid phase. The nature of the head (β-diketonate or carboxylate) or tails and substituents of β-diketonates appeared not to be important for the formation of the liquid phase. It is worth mentioning that Pb(OAc)2, which has limited use due to its low solubility, was successfully adopted as a starting material for the preparation of new lead complexes. Easy hydrolysis, reaction with HCl, and 13C NMR spectra indicated that tail portions were not coordinated to the metal as a copper derivative, Cu(t-BuC(O)CHC(O)(CH2)3OMe)2. All these complexes were not volatile enough for the MOCVD experiments, but a methyl derivative, Pb(MeC(O)CHC(O)(CH2)3OEt)2, showed some sublimation. The methoxy derivative, Pb(MeOC(O)CHC(O)(CH2)3OEt)2, was thermally unstable due to possible equilibrium between species coordinating with a keto oxygen atom and an ethereal atom of a methoxy group, which was confirmed by IR and 13C NMR spectra.

• Applied Chemistry for Engineering
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• v.4 no.4
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• pp.785-790
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• 1993

Three ester-type chitin derivatives were synthesized by reacting chitin with acetic anhydride, propionic anhydride and n-butyric anhydride to form acetyl chitin(AC), propionyl chitin(PC) and n-butyryl chitin(BC). Methanesulfonic acid was used as a catalyst. FT-IR spectra and solid state CP/MAS $^{13}C-NMR$ spectra of three chitin derivatives showed that the substituents were mainly incorporated in the $C_6$ position of chitin. The ester-type chititn derivatives were dissolved well in formic acid and swollen in aqueous acidic solution.