• Archives of Pharmacal Research
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• v.29 no.1
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• pp.46-49
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• 2006

In this study, 2-N-arylimino-2,3-dihydro-1,3,4-thiadiazoles derivatives (6a-h) were synthetized. The mechanism of the studied reactions was discussed. The chemical structures of the compounds were elucidated by their IR, $^1H-NMR,\;^{13}C-NMR$, and Mass spectral data and elemental analyses. The compounds were tested for antimicrobial activity using diffusion agar technique.

• Bulletin of the Korean Chemical Society
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• v.32 no.10
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• pp.3644-3649
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• 2011

Multinuclear solid-state nuclear magnetic resonance (NMR) experiments were performed to investigate the local structure changes of nanoporous silica during hydrothermal treatment and surface modification with 3-aminopropyltriethoxysilane (3-APTES). The nanoporous silica was prepared by sol-gel polymerization using inexpensive sodium silicate as a silica precursor. Using $^1H$ magic angle spinning (MAS) NMR spectra, the hydroxyl groups, which play an important role in surface reactions, were probed. Various silicon sites such as $Q^2$, $Q^3$, $Q^4$, $T^2$, and $T^3$ were identified with $^{29}Si$ cross polarization (CP) MAS NMR spectra and quantified with $^{29}Si$ MAS NMR spectra. The results indicated that about 25% of the silica surface was modified. $^1H$ and $^{29}Si$ NMR data proved that the hydrothermal treatment induced dehydration and dehyroxylation. The $^{13}C$ CP MAS and $^1H$ MAS NMR spectra of 3-APTES attached on the surface of nanoporous silica revealed that the amines of the 3-aminopropyl groups were in the chemical state of ${NH_3}^+$ rather than $NH_2$.

• Bulletin of the Korean Chemical Society
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• v.30 no.5
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• pp.1039-1042
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• 2009

RNA polymerase II C-terminal domain phosphatase 1 containing ubiquitin like domain (UBLCP1) has been identified as a regulatory molecule of RNA polymerase II. UBLCP1 consists of ubiquitin like domain (UBL) and phosphatase domain homologous with UDP and CTD phosphatase. UBLCP1 was cloned into the E.coli expression vectors, pET32a and pGEX 4T-1 with TEV protease cleavage site and purified using both affinity and gel-filtration chromatography. Domains of UBLCP1 protein were successfully purified as 7 mg/500 mL (UBLCP1, 36.78 KDa), 32 mg/500 mL (UBL, 9 KDa) and 8 mg/500 mL (phosphatase domain, 25 KDa) yielded in LB medium, respectively. Isotope-labeled samples including triple-labeled ($^2H/^{15}N/^{13}C$) UBLCP1 were also prepared for hetero-nuclear NMR experiments. $^{15}N-^{1}H$ 2D-HSQC spectra of UBLCP1 suggest that both UBL and phosphatase domain are properly folded and structurally independent each other. These data will promise us further structural investigation of UBLCP1 by NMR spectroscopy and/or X-ray crystallography.

• Natural Product Sciences
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• v.4 no.4
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• pp.245-252
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• 1998

The unique sulphated phenolics, gallic acid 3-methyl ether 5-potassium sulphate, isoferulic acid 3-potassium sulphate, and ellagic acid 4,4'-dimethyl ether 3-potassium sulphate have been isolated from the flowers of Tamarix amplexicaulis Ehrenb. (Tamaricaceae). The hitherto unknown natural phenolic acid, gallic acid 3-methyl ether, together with the known phenolic, gallic acid, gallic acid 4-methyl ether, isoferulic acid, ferulic acid, ellagic acid, and ellagic acid 4,4'-dimethyl ether have been also separated and characterized. The structures were established by conventional methods, including electrophoretic analysis and confirmed by ESI-MS, $^1H-\;and\;^{13}C-NMR$.

• Applied Biological Chemistry
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• v.40 no.1
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• pp.85-88
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• 1997

In orther to isolate antibacterial substances from the flower of Chrysanthemum zawadskii Herbich var. latilobum Kitam., the chloroform fraction was fractionated according to the activity against B. subtilis, S. aureus and V. parahaemolyticus. Two antibacterial substances were isolated and purified by preparative TLC and recrystallization. Compound I showed activity against all the tested bacteria and compound II exhibited the activity against B. subtilis and v. parahaemolyticus except S. aureus. Compared to benzoic acid and sorbic acid which are being used as food preservatives, compounds I and II showed about five-fold stronger antibacterial activity against B. subtilis and V. parahaemolyticus. On the basis of spectrometric studies including $^1H-NMR,\;^{13}C-NMR,\;DEPT,\;^1H-^1H\;COSY,\;^{13}C-^1H\;COSY$ and Mass, compounds I and II were identified as angeloylcumambrin B and cumambrin A, respectively. This is the first report of the isolation of angeloylcumambrin B and cumambrin A from this plant.

• Applied Biological Chemistry
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• v.46 no.2
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• pp.69-73
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• 2003

A novel antifungal antibiotic for azole-resistant Candida albicans was purified from the culture broth of Bacillus subtilis LAM 97-44 by butanol extraction, Diaion HP-20 and Dowex-50 adsorption chromatography, silica gel flash chromatography followed by HPLC and designated LAM-44A. LAM-44A was stable for 60 min at $100^{\circ}C$, and pH range from 2 to 10. MIC values were observed at $0.5-3.5\;{\mu}g/ml$ against various Candida albicans strains. The antibiotic showed no cytotoxicity for S180, MKN-45, P388, HeLa and 373 at the concentration of 1 mg/ml. LAM-f4A was colorless powder soluble in water, methanol, ethanol, butanol and negative to ninhydrin reaction. The antibiotic had maximum absorption at 273 nm in methanol, and melting point was $202^{\circ}C$. The molecular weight and formula were determined to be 282 and $C_{14}H_{34}O_5$ by $^1H-NMR,\;^{13}C-NMR$, IR spectrum and elemental analysis.

• Journal of Microbiology and Biotechnology
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• v.16 no.10
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• pp.1591-1596
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• 2006

Acaricidal effects of materials derived from Caesalpinia sappan heartwoods against Dermatophagoides farinae and D. pteronyssinus were assessed and compared with those evidenced by commercial benzyl benzoate and DEET. The observed responses varied according to dosage and mite species. The $LD_{50}$ values of the methanol extracts derived from C. sappan heartwoods were 6.13 and $5.44{\mu}g/cm^3$ against D. farinae and D. pteronyssinus, respectively. Furthermore, the ethyl acetate fraction derived from the methanol extract was approximately 8.71 more toxic than DEET against D. farinae, and 4.73 times more toxic against D. pteronyssinus. The biologically active constituent from the ethyl acetate fraction of C. sappan heartwood extract was purified via silica gel chromatography and high-performance liquid chromatography. The structure of the acaricidal component was analyzed by $GC-MS,\;^1H-NMR,\;^{13}C-NMR,\;^1H-^{13}C\;COSY-NMR$, and DEPT-NMR spectroscopy, and identified as juglone (5-hydroxy-l,4-naphthoquinone). Based on the $LD_{50}$ values of juglone and its derivatives, the most toxic compound against D. farinae was juglone ($0.076{\mu}g/cm^3$), followed by benzyl benzoate ($9.143{\mu}g/cm^3$) and 2methyl-l,4-naphthoquinone ($40.0{\mu}g/cm^3$). These results indicate that the acaricidal activity of C. sappan heartwoods is likely to be the result of the effects of juglone. Additionally, juglone treatment was shown to effect a change in the color of the cuticles of house dust mites, from colorless-transparent to dark brownish-black. Accordingly, as a naturally occurring acaricidal agent, C. sappan heartwood-derived juglone should prove to be quite 'useful as a potential control agent, lead compound, and house dust mite indicator.

• Applied Biological Chemistry
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• v.46 no.3
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• pp.246-250
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• 2003

In order to isolate antibacterial substances from the rhizome of Zingiber mioga Roscoe, the ethanol extracts was fractionated according to the activity against Bacillus subtilis, B. cereus and Staphylococcus aureus. Three antibacterial substances were isolated and purified by column chromatography and recrystallization. Compounds I and III showed activity against all the tested bacterias and compound II exhibited the activity against B. subtilis and B. cereus S. aureus. Compound I was examined antimicrobial activity against B. subtilis, B. cereus and S. aureus by optical density using Bioscreen C. Compound I showed strong growth inhibition at 10 ppm on B. subtilis and B. cereus for 72 hrs, and at 25 ppm on S. aureus. On the basis of spectrometric studies including $1^H-NMR$, ${13}^C-NMR$, DEPT, IH-lH COSY, HMQC, HMBC and IR, compounds I, II and III were identified as $(E)-8{\beta}(17)-epoxylabd-12-ene-15,16-dial\;(C_{20}H_{30}O_3,\;MW=318)$, galanolactone $(C_{20}H_{30}O_3\;MW=318)$ and galanal A $(C_{20}H_{30}O_3,\;MW=318)$, respectively. These results are the first reports on the isolation of $(E)-8{\beta}(17)-epoxylabd-12-ene-15,16-dial, galanolactone and galanal A from the rhizome of Zingiber mioga.

• Journal of Korea Foresty Energy
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• v.21 no.1
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• pp.41-48
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• 2002

The barks of oak trees (Quercus acutissima and Quercus variabilis) were collected, extracted with acetone-$H_2O$ (7:3, v/v), fractionated with hexane, $CH^2C1^2$ EtOAc and -$H_2O$, then freeze dried to give dark brown powder. The EtOAc soluble mixtures of the trees were chromatographed on a Sephadex LH-20 column using a series of aqueous methanol and ethanol-hexane mixture as eluents. The structures of isolated compounds were characterized by $^1H$, $^13C$ and 2D-NMR spectroscopy and molecular weights were determined by FAB-MS spectra. The isolated compounds from Quercus acutissima were (+)-catechin, (+)-gallocatechin, gallic acid and taxifolin-3-O-$\beta$-D-glucopyranoside and the compounds from Quercus variahilis (+)-catechin, caffeic acid and taxifolin-3-O-$\beta$-D-glucopyranoside.

• Archives of Pharmacal Research
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• v.20 no.2
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• pp.176-179
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• 1997

Purine nucleosides were chlorinated by the reaction of acyl chloride in DMF with MCPBA under mild conditions with moderate yields. And, satisfactory method for the synthesis of ribonucleoside-$3^{I},5^{I}$-cyclic phosphates and its characterization by$^{1}H$ and $^{13}C$ nmr spectroscopy is described.