• 제목/요약/키워드: $^{11}B$ NMR

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Characteristics of the Multi-Hydrogen Bonded Systems: DFT Description on the Solvated Electrons

  • Xu, Jun
    • Bulletin of the Korean Chemical Society
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    • 제34권11호
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    • pp.3265-3268
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    • 2013
  • The multi-hydrogen bonded systems with the solvated electrons are investigated at the B3LYP/6-311++$G^{**}$ basis set level. The symmetrical linear geometrical characteristic is common for the dimer systems, while for the tetramer system, the tetrahedron configuration is generated. The NBO charge analyses demonstrate that the multi-hydrogen-multi-electron (mH-ne) coupling exist in these anion systems, as is supported by the electrostatic potential and the molecular orbital analyses. The positive chemical shift value of the central hydrogen ($H_c$) and the negative chemical shift value of the terminal hydrogen ($H_t$) indicate that the $H_c$ is electronegative while the $H_t$ is electropositive, respectively. Strong coupling between two central hydrogen atoms is demonstrated by the large spin-spin coupling constants. The solvated electron donates significant contributions for the stability of these systems.

Flavonoids from Iris spuria (Zeal) Cultivated in Egypt

  • Singab, Abdel Nasser B.
    • Archives of Pharmacal Research
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    • 제27권10호
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    • pp.1023-1028
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    • 2004
  • A new 12a-dehydrorotenoid 1, 11-dihydroxy-9, 10-methylenedioxy-12a-dehydrorotenoid (1), together with a new isoflavonoid glycoside tectorigenin-7-O-${\beta}$-glucosyl-4'-O-${\beta}$-glucoside (3), were isolated and identified from the rhizomes of I. spuria (Zeal). In addition, 4 known compounds, tectorigenin (2) tectorigenin-7-O-${\beta}$-glucosyl $(1{\leftrightarrow}6)$ glucoside (4), tectoridin (a tectorigenin- 7-O-${\beta}$-glucoside) (5) and tectorigenin-4'-O-${\beta}$-glucoside (6) were isolated and identified for the first time from this plant. The structures of the isolated compounds were determined by spectroscopic methods (UV, IR, $^1H,\;^{13}C$NMR, DEPT, HMQC, NOESY, and HMBC experiments and MS spectrometry) and by comparison with literature data of known compounds. Compounds 2, 4, 5, and 6 are reported for the first time from this plant through the present study.

로즈마리(Rosmarinus officinalis L.) 추출물로부터 Helicobacter pylori에 대한 항균물질 분리 및 동정 (Isolation and Identification of Antimicrobial Compounds against Helicobacter pylori from Rosemary (Rosmarinus officinalis L.) Extracts)

  • 윤소정;김진성;조분성;김정환;이선호;안봉전;조영제
    • Journal of Applied Biological Chemistry
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    • 제54권3호
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    • pp.159-165
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    • 2011
  • 로즈마리 추출물의 phenol 함량은 25.7 mg/g으로 매우 높게 나타났다. Helicobacter pylori 에 대한 항균효과를 측정한 결과, clear zone이 $100{sim}200{\mu}/disc$의 phenol 농도에서 각각 11, 12, 14 mm의 clear zone을 형성하여 추출물의 농도가 증가할수록 H. pylori 에 대한 저해효과가 농도 의존적으로 높아지는 것을 확인 할 수 있었다. Sephadex LH-20과 MCI-gel CHP-20 column을 이용하여 normal phase type인 $ethanol{\rightarrow}H_2O$와 reverse phase type인 $H_2O{\rightarrow}methanol$로 용액의 농도를 증가시키면서 용출한 결과 H. pylori에 대한 탁월한 저해활성을 나타낸 5종류(compound A~E)의 단일 물질로 분리하였다. 5가지 각각의 물질은 H. pylori에 대한 항균력이 미약하였으나, 2종류 이상의 다중 물질의 항균 시너지 효과에 의해 각각 10~16 mm의 clear zone을 형성하여 우수한 항균력을 나타내었으며, fast atom bombardment (FAB)-Mass, $^1H$-NMR, $^{13}C$-NMR과 IR spectrum을 사용하여 구조 동정한 결과 protocatechuic acid, coumaric acid, caffeic acid, chlorogenic acid 및 rosmarinic acid 인 것으로 확인되었다.

Discokiolide B의 합성에 관한 연구 (Synthetic Studies on Discokiolide B)

  • 김홍석;김상화;이주영
    • 대한화학회지
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    • 제40권11호
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    • pp.692-698
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    • 1996
  • 해양천연물 Discokiolide B의 옥사졸 골격인 discokiic acid 1을 합성하였다. 2[2'-(4-Phenyl-3-butenyl)]-1, 3-oxazole-4-carboxaldehyde(4a)와 methyl propionate의 리튬 enolate와의 알돌반응으로부터 discokiic acid methyl ester를 합성하였다. 중요한 반응중간체인 2[2'-(4-Phenyl-3-butenyl)]-1, 3-oxazole-4-carboxaldehyde(4a)는 디아조 말론알데히드와 니트릴을 로듐촉매하에서 반응시켜 얻었다. Discokiic acid의 오른쪽 측쇄 부분인 3-hydroxy-2-methyl 프로판산 부분의 상대적인 입체화학을$^1H$$^{13}C$ 핵자기공명 데이터에 근거하여 결정하였다.

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YNi$_2B_2C$의 초전도 상태에서 국소자기장의 분포 (Local Field Distribution in YNi$_2B_2C$ Superconductor)

  • 김도형;이규홍;한기성;서승원;이무희;이성익;조병기
    • 한국초전도학회:학술대회논문집
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    • 한국초전도학회 1999년도 High Temperature Superconductivity Vol.IX
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    • pp.251-255
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    • 1999
  • Local field distribution in the mixed state of type II superconductors has been numerically calculated and compared with $^{11}$B NMR spectra for YNi$_2B_2C$ single crystals. We find that only small distortion of vortex positions from the perfect lattice points is enough to smear out the low frequency shoulder. As the vortices are further distorted, the line shape changes from an asymmetric shape with a high frequency tail to a symmetric Gaussian line shape. It is found that the second moment of the field distribution has a major contribution from the high frequency tail. Consequently, a linewidth of the full width at half maximum calculated from the second moment assuming for a Gaussian line shape is overestimated.

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Phytochemical and Pharmacological Investigations on Moringa peregrina (Forssk) Fiori

  • Elbatran, Seham A.;Abdel-Salam, Omar M.;Abdelshfeek, Khaled A.;Nazif, Naglaa M.;Ismail, Shams I.;Hammouda, Faiza M.
    • Natural Product Sciences
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    • 제11권4호
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    • pp.199-206
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    • 2005
  • Investigation of M. peregrina aerial parts revealed the isolation and identification of 4-flavonoidal compounds, quercetin, quercetin-3-0-rutinoside (rutin), chrysoeriol-7-0-rhamnoside 6,8,3',5'-tetramethoxy apigenin. The compounds were identified by TLC, PC, MS, and $H^1-NMR$. The fatty acids and unsaponifiable matter were studied. The $LD_{50}$ for M. peregrina was 113.4 mg/100g b.wt. Repeated intraperitoneal injection of 1/20 and 1/10 $LD_{50}$ (5.67 mg and 11.34 mg/100g b.wt.) of defatted alcoholic of M. peregrina for 30 days induced significant decrease in serum glucose, liver enzymes and lipid components. M. peregrina administered i.p., 30min prior to carrageenan at the above doses significantly inhibited the rat paw oedema response, In acute pain models, namely, the acetic acid-induced writing and hot-plate assay, M. peregrina exhibited marked analgesic properties. In addition, M. peregrina administered at time of indomethacin injection inhibited the development of gastric lesions in rats.

오징어(Omnastrephes bartrami) 간지질(肝脂質)에 존재(存在)하는 Ethyl Acylates의 구조(構造)와 그 구성(構成) 지방산(脂肪酸) 조성(組成)에 관한 연구(硏究) (The Presence of Ethyl Acylates in the Liver Lipids of A Squid, Omnastrephes bartrami and Their Fatty Acid Composition)

  • 조연주;조용계
    • 한국응용과학기술학회지
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    • 제7권2호
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    • pp.19-32
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    • 1990
  • Lipid levels in the tissues of liver and intestines of O.bartrami amounted to 40.0% and 1.5%. The new compounds was found to be ethyl acylates, from a deduction of their detailed $^1H-nuclear$ magnetic resonance(NMR) and $^{13}C-NMR$ as well as infra red spectra (IR). The fatty acid composition of total lipids were mainly composed of C16:0(19.0%), C18:1(16.2%) and $C22:6{\omega}3$(15.7%), followed by C20:1(9.4%), C22:1(6.4%) and C18:0(5.4%). New compound A and B were seemed to derived from the cleavage of glycerol moieties of triglycerides by microbial activities during storage in a frozen state. Compound A contained C16:0(38.2%), C18:1(13:4%), C20:1(13.3%) and C22:1(11.7%) as major components, while compound B predominantly comprised polyunsaturated fatty acid such as $C20:5{\omega}3$ (41.2%) and $C22:6{\omega}3$(36.1%). In both compounds small amounts of odd numbered fatty acids were also detected ($3.8{\sim}2.2%$).

Bacillus alkalophilshaggy JY-827가 생산하는 항우식균물질의 생산조건과 분리, 정제 및 특성 (Production Condition, Purification and Properties of Anticaries Microbial Agent by Bacilluse alkalo-philshaggy JY-827)

  • 전주연;류일환;이상욱;이갑상
    • 한국미생물·생명공학회지
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    • 제28권5호
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    • pp.270-278
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    • 2000
  • The study was performed to investgate the excellent microbial anticaries substance which is more effective that the chlorhexidine in the dental caries treatment. A typi-cal strain which produced the most excellent antimicrobial subatance was selected. and identified novel alkalophillic Bacillus alkalophilshaggy JY-827. For the maximal production of themicrobial antibiotic against Streptococcus mutans from B. alkalophilshaggy JY-827, the optimal culture condition was in the medium containing glucose 15g/ L, pepton 10g/L and $K_2$$HPO_4$ 2g/L the highest production of antibiotic against S.mutans was obtained at $25^{\circ}C$ and pH 11.0 for 5 days. The antibiotic from B. alkalophilshaggy JY-827 was purified by organic solvent extraction, silica gel and sephadex LH-20 column chromatograpies, and then crystallized with methanol. The crystallin compoma-tion of this antibiotic was as a curcular shape. The melting point and rm[$\alpha$]$D^{20}$ were 152-154$^{\circ}C$ and +55。, respec-tively. Based on Instumental analyses such as FT-IR, $^{1}$H-NMR $^{13}$ C-NMR and GC-mass, the antibiotic was identified as aminoglycoside. It was obtained as amorphous white power, and soluble in water power, and soluble in water, methanol but insoluble in ether, chroloform. This antibiotic inhibited the growth of S.mutans to about 3 day at the concentration of $2.5$\times$10^{-7}$ /M. It was stable at the alkalli condition but unstable within the acid condition. It was also stable up to $70^{\circ}C$.

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질경이로부터 항균성 화합물의 분리 및 동정 (Isolation and Identification of Antimicrobial Compound from Plantain (Plantago asiatica L.))

  • 김건희;김순임;한영실
    • 한국식품조리과학회지
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    • 제15권4호
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    • pp.410-417
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    • 1999
  • 우리나라 야산에서 쉽게 구할 수 있는 구황 식물인 질경이를 메탄올과 여러 용매로 추출하여 식품 부패 미생물에 대한 항균력을 실험하고 그 항균활성 물질을 분석하여 다음과 같은 결과를 얻었다. 질경이의 메탄올 추출물은 2000$\mu\textrm{g}$/ml 농도에서 B. subtilis 및 V. parahaemolyticus의 증식을 100% 억제하였다. 그리고 질경이의 ethylacetate 분획물은 1000$\mu\textrm{g}$/disc 농도에서 5종의 모든 실험 균주에 대하여 8.5~11mm 크기의 clear zone을 형성하여 가장 높은 항균력을 보였다. 질경이의 ethylacetate 분획물을 silica gel column chromatography와 TLC로 분리하여 얻은 fraction을 5가지 실험 균주에 대하여 항균 실험을 한 결과 3rd 분획물 중 4번째 분획물이 250$\mu\textrm{g}$/disc 농도에서 모든 균주에 대하여 10 mm 이상의 clear zone을 나타내었다. 항균력을 보인 질경이의 ethylacetate 3rd fraction No. 4를 HPLC로 단일 분리하여 얻은 peak IV로 부터 $^1$H-NMR 및 GC-MSD로 동정한 결과 hexadecanoic acid로 동정되었다.

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버섯균사체 배양물로부터 면역증진 기능성 소재 개발

  • 김정옥
    • 식품저장과 가공산업
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    • 제6권2호
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    • pp.11-13
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    • 2007
  • This study relates to low and medium molecular weight isoflavone-${\beta}$-D-glucan produced by submerged liquid culture of Agaricus blazei, a method of producing the isoflavone-B-D-glucan using autolysis enzyme of Agaricus blazei mycelia, and use of the isoflavone-B-D-glucan for anti-cancer and immunoenhancing effect. In acordance with one aspect of the present study, it deals with a method of producing isoflavone-${\beta}$-D-glucan, which comprises the followings; 1) culturing and separating mushroom mycelia, 2) producing low-medium molecular weight isoflavone-${\beta}$-D-glucan from high molecular weight one. The cytotoxicity on human cnacer cell line (Caco-2, MCF-7), the expression of Cyclin D, Bcl-2, Bax protein, p21 protein, p53 protein in MCF-7 cells assessed by SDS-PAGE and immunoblotting, and other immuno related factor such as TNF-a and IL-1B activities were examined. Structural identification of isoflavone-${\beta}$-D-glucan which shoed cytotoxicity against cancer cell and immunoenhancing effects was carried by separation with DEAE-cellulose column chromatography, TLC, HPLC, IR, NMR, Clinical test for the cancer patients (n=119) for 6 month was carried out, and immunoenhancing factors(NK cell number, ratio of T4/T8) were checked. We concluded the identified isoflavone-${\beta}$-D-glucan has immuno enhancing effects and could be useful for cancer chemoprevention.

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