• Title/Summary/Keyword: $^1H-^{13}C\

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Metal Complexes of Ambidentate Ligand (VI). Palladium(II) Complexes of Isonitrosoethylacetoacetate Imines (Ambidentate 리간드의 금속착물 (제 6 보). Isonitrosoethylacetoacetate Imine 리간드의 팔라듐 (II) 착물)

  • Jun Young-Sook;Lee Man-Ho;Kim In-Whan;Kim Soo-Han
    • Journal of the Korean Chemical Society
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    • v.35 no.4
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    • pp.368-373
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    • 1991
  • Palladium(II) complexes of the type Pd(IEAA-NR)$_2$ (R = H, CH$_3$, C$_2$H$_5$, n-C$_3$H$_7$, n-C$_4$H$_9$, or CH$_2$C$_6$H$_5$), where IEAA-NR represents N-alkyl derivative of isonitrosoethylacetoacetate (H-IEAA) imine, have been prepared. And the structure of the complexes have been studied by elemental analyses, electronic, infrared, $^1$H and $^{13}$C-NMR spectra. It is proposed that both of IEAA-NR ligands coordinate to metal through nitrogens of imine and isonitroso groups to form 5-membered chelate rings in the complexes.

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Phase Equilibria and Reaction Paths in the System Si3N4-SiC-TiCxN1-x-C-N

  • H.J.Seifert
    • Journal of Powder Materials
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    • v.6 no.1
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    • pp.18-35
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    • 1999
  • Phase equilibria in the system Si3N4-TiC-TiCxN1-x-C-N were determined by thermodynamic calculations (CALPHAD-method). The reaction peaction paths for Si3N4-TiC and SiC-TiC composites in the Ti-Si-C-n system were simulated at I bar N2-pressure and varying terpreatures. At a temperature of 1923 K two tie-triangles (TiC0.34N0.66+SiC+C and TiC0.13N0.87+SiC+Si3N4) and two 2-phase fieds (TiCxN1-x+SiC; 0.13

Synthesis and Analysis of 6,6-dichlorobicyclo[3, 1, 0]hexane-3-carboxylic acid (6,6-Dichlorobicyclo[3, 1, 0]hexane-3-carboxylic acid의 합성과 분석)

  • Lee, Kwang-Soo;Yang, Jae-Kun
    • Analytical Science and Technology
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    • v.14 no.1
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    • pp.1-7
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    • 2001
  • 6,6-Dichlorobicyclo[3, 1, 0]hexane-3carboxylic acid was synthesized by dichlorocarbene addition into 3-cyclopentenecarboxylic acid using BTEA.Cl as phase transfer catalyst. $^1H$ NMR $^{13}C$ NMR data analyst showed that this compound had boat-like conformation and carboxyl group existed as trans form.

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Ethanol Production an Immobilized Themotolerant Mutant of Brettanomyces custersii H1-39 from Wood Hydrolyzate Media (목질계 당화액배지로부터 고온내성 변이주 Brettanomyces custersii H1-39의 고정화에 의한 에탄올생산)

  • 박승원;홍영기;김승욱;홍석인
    • Microbiology and Biotechnology Letters
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    • v.28 no.3
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    • pp.172-179
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    • 2000
  • Bretlanomyces C!tstersii Hl-39 mutant was immobilized with various caniers. Immobilized mutant Hl-39 produced more ethanol and showed higher productivity and cell concentration than those of free 81-39 in 3.4% hydrolyzate of wood-chips at different temperatures ($37^{\circ}C$, $40^{\circ}C$ and $43^{\circ}C$). At $37^{\circ}C$, ethanol concentration produced by mutant H1-39 immobilized in Ca-alginate and ARG(l % Ca-alginate, 1.67% bentonite, 0.33% glutaraldehyde) bead were higher than those produced by the other earners (ACG ; 1 % CaHalginate. ] .67% celite R-634 , 0.33% glutaraldehyde, ABP ; 1 % Ca-alginate. 1.67% bentonite, 0.33% pectin. ACP: 1 % Ca-alginate, ] .67% celiLe R-634, 0.33% pecLin). The highest value of productivity(l.23 ) was obtained by using ABG beads. At $40^{\circ}C$, ethanol conccntration and productivity obtained by ABC beads ,>,"ere 15.2 glL and 0.84 gl L.h, respectively, which showed the highest value compared to other carriers. Particularly, productivity of ilmnobilized ceIl was increased up to 90% as compared to that offree cell. On the other hand, ABP(l % Ca-alginate+L67% bentonile+O.33% pectin) beads gave the best resulLs at $43^{\circ}C$ for production of ethanol and productivity, which were 13.8 g!l and 0.77 g/l h, respectively.ively.

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Confirmation of Enzymatic Synthesis of 1, 2-Octanediol Galactoside using Mass Spectrometry and NMR Spectroscopy (Mass spectrometry와 NMR Spectroscopy를 이용한 1, 2-Octanediol Galactoside의 효소합성 확인)

  • Lee, Hyang-Yeol;Jin, Hong-Jong;An, Seung Hye;Lee, Hye Won;Jung, Kyung-Hwan
    • Journal of the Korean Applied Science and Technology
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    • v.38 no.3
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    • pp.824-831
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    • 2021
  • 1, 2-Octanediol galactoside (OD-gal) has been synthesized from 1, 2-octanediol (OD), as a safer cosmetic preservative, using recombinant Escherichia coli β-galactosidase (β-gal). To confirm the molecular structure of synthesized OD-gal, mass spectrometry and NMR (1H- and 13C-) spectroscopy of OD-gal were carried out. In the reaction mixture, a sodium adduct ion of OD-gal (m/z=331.1732) was identified using mass spectrometry analysis. In addition, 1H NMR spectrum of OD-gal showed multiple peaks corresponding to the galactosyl group, which is evidence of galactosylation on OD. Downfield proton peaks at δH 4.39 ppm and multiple peaks from δH 3.98~3.55 ppm were indicative of galactosylation on OD. Up field proton peaks at δH 1.52~1.26 ppm and 0.89 ppm showed the presence of CH2 and CH3 protons of OD. 13C NMR spectrum revealed the presence of 24 carbons suggestive of α- and β-anomers of OD-gal. Among 14 carbon peaks from each anomer, the 4 peaks at δC 31.4, 29.0, 22.3, and 13.7 ppm were assigned to be overlapped showing only 24 peaks out of a total of 28 peaks. The mass value from mass spectrometry analysis of OD-gal, and 1H and 13C NMR spectral data were in good agreement with the expecting structure of OD-gal. Finally, we identified a galactose molecule from the hydrolysate of OD-gal using β-gal. We are expecting that through future study it will eventually be able to develop a safe cosmetic preservative.

The Crystal Structure of Cantharidin $(C_{10}H_{12}O_{4})$ (Cantharidin$(C_{10}H_{12}O_{4})$의 결정 구조)

  • 김문집;박호종;김대영;이종수
    • Korean Journal of Crystallography
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    • v.13 no.2
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    • pp.91-95
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    • 2002
  • The structure of Cantharidin (Hexahydro-3a,7a-dimethy1-4,7-epoxyisobenzofuran-1,3-dione, C/sub 10/H/sub 12/O/sub 4/)has been determined by X-ray diffraction methods. The crystal system is orthorhombic, space group Pna2/sub 1/, unit cell constants, a=11.0731(9) (equation omitted), b=6.7344(4) (equation omitted), c=12.5000(9) (equation omitted), α=β=γ=90°, V=932.13(12) (equation omitted), T=296K, Z=4, D/sub c/=1.398Mgm/sup -3/. The intensity data were collected on an Enraf-Nonius CAD-4 Diffractometer with graphite monochromated MoKα radiation(λ=0.71073(equation omitted)). The molecular structure was solved by direct methods and refined by full-matrix least squares to a final R=4.42% for 759 unique observed F/sub o/>4σ(F/sub o/) reflections and 140 parameters.

Suppressive Effects of Cyanidin-3-glucoside on Th2 Cytokines Production in RBL-2H3 Cells (RBL-2H3 세포에서 Cyanidin-3-glucoside의 Th2 사이토카인 발현 억제 효과)

  • Jeong, Hwa Hyun;Yoon, Soo Jeong;Pyo, Myoung Yun
    • YAKHAK HOEJI
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    • v.57 no.5
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    • pp.309-315
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    • 2013
  • Cyanidin-3-glucoside (C3G), an anthocyanin, is one of the most widespread dietary flavonoids. We investigated the effects of C3G in PMA/ionomycin (PI)-induced RBL-2H3 cells. C3G inhibited the production of IL-4 and IL-13 and also decreased the level of mRNA in a dose-dependent manner. Furthermore, western blot analysis implied that C3G down-regulated the protein level of c-Jun, NF-ATc1 and NF-${\kappa}B$ but not c-Fos. Taken together, we suggest that C3G may have suppressive effects on Th2 cytokines and will be studied further to develop as functional foods that help alleviate allergy symptoms.

Study on DC Characteristics of 4H-SiC Recessed-Gate MESFETs (Recessed-gate 4H-SiC MESFET의 DC특성에 관한 연구)

  • Park, Seung-Wook;Hwang, Ung-Jun;Shin, Moo-Whan
    • Korean Journal of Materials Research
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    • v.13 no.1
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    • pp.11-17
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    • 2003
  • DC characteristics of recessed gate 4H-SiC MESFET were investigated using the device/circuit simulation tool, PISCES. Results of theoretical calculation were compared with the experimental data for the extraction of modeling parameters which were implemented for the prediction of DC and gate leakage characteristics at high temperatures. The current-voltage analysis using a fixed mobility model revealed that the short channel effect is influenced by the defects in SiC. The incomplete ionization models are found out significant physical models for an accurate prediction of SiC device performance. Gate leakage is shown to increase with the device operation temperatures and to decrease with the Schottky barrier height of gate metal.

Flavonol Glycosides from Parthenocissus tricuspidata Leaves (담쟁이덩굴엽의 플라보놀 배당체)

  • 황현경;성환길;황완균;김일혁
    • YAKHAK HOEJI
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    • v.39 no.3
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    • pp.289-296
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    • 1995
  • For the investigation of medicinal resources the studies were carried out to evaluated the pharmaco-constituents in the Leaves of Parthenocissus tricuspidata(Vitaceae), of which leaves have been used in Korea as folk remedies for the treatments of arthritis, jaundice, toothache, neuralgia, and etc. From 1-butanol fraction of the MeOH extract, Compound I ($C_{21}H_{18}O_{13}$, Quercetin-3-O-$\beta$-D-glucuronopyranoside), Compound II ($C_{21}H_{20}O_{12}$, Quercetin-3-O-$\beta$-D-glucopyranoside) and Compound III ($C_{25}H_{28}O_{12}$, Quercetin-3-O-(6"-n-butyl)-$\beta$-D-glucuronopyranoside) were isolated by column chromatographic separation using Sephadex LH-20 and ODS gel. Their structures were elucidated through instrumental analyses, such as $^{1}H$-NMR, $^{13}C$-NMR, IR, UV, El-Mass, FAB-Mass and GC. Especially compound III was Flavonol glycoside and named parthenosin.

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