• 제목/요약/키워드: nuclear magnetic resonance spectroscopy (NMR)

검색결과 238건 처리시간 0.028초

Donor-Acceptor 발색단과 디케토피롤로피롤(DPP) 유도체에 관한 연구 (The Study of Donor-Acceptor Chromophores and Diketopyrrolopyrrole(DPP) Analogues)

  • 김헌수;김승회;박수열
    • Tribology and Lubricants
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    • 제32권5호
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    • pp.141-146
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    • 2016
  • The diketopyrrolopyrrole (DPP) pigment is a bicyclic 8-π-electron system containing two lactam units. Typical DPP derivative pigments have melting points of over 350°C and very low solubility in most solvents, and show absorption in the visible region with a molar extinction coefficient of 33,000 dm2mol−1 and strong photoluminescence with maxima in the range 500–600 nm. X-ray structure analyses of DPP show that the whole molecule is almost in one plane. The phenyl rings are twisted out of the heterocyclic plane and the intermolecular hydrogen bonding between neighboring lactam NH and carbonyl units influences the structure of the DPP pigment in the solid state. In this study, mono-N-alkylation and mono-N-arylation were undertaken for Pigment Red 264 or Pigment Orange 73 with alkyl halide and aryl halide, respectively, in the presence of sodium tert-butoxide as a base catalyst to improve the solubility of DPP pigments and their application as CO2 indicators. The synthetic yield was in the range 11–88%. The indicator dyes are highly soluble in organic solvents and shows pH-dependent absorption (λmax 501 and 572 nm for the protonated and deprotonated forms, respectively) and emission (λmax 524 and 605 nm for the protonated and deprotonated forms, respectively) spectra. The mono-N-alkylated and mono-N-arylated DPP pigment was identified by 1H-NMR (1H-Nuclear Magnetic Resonance Spectrometer), FT-IR (Fourier Transform Infrared Spectroscopy), and MS (Mass Spectrometry). According to the results of color and hue properties obtained by a color matching analyzer, the synthesized DPP pigment material can be used as a CO2 indicator.

Characterization of by-products from organosolv pretreatments of yellow poplar wood (Liriodendron tulipifera) in the presence of acid and alkali catalysts

  • 곽기섭;구본욱;박나현;정한섭;최준원;여환명;최인규
    • 한국신재생에너지학회:학술대회논문집
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    • 한국신재생에너지학회 2009년도 추계학술대회 논문집
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    • pp.520-520
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    • 2009
  • Organic by-products derived from cellulose and lignin during organosolv pretreatments of yellow poplar wood (Liriodendron tulipifera) in the presence of $H_2SO_4$ and NaOH as catalysts, respectively, were subjected to various analyses to elucidate their effects on further performance of biological ethanol fermentation and provide preliminary data for the structure and utilization of organosolv lignin. Monomeric sugars amounted to ca. 2.2-7.7% in the organosoluble fraction of the organosolv pretreatment with $H_2SO_4$, while significantly low amount of sugars (0.2-0.3%) were determined in that of the organosolv pretreatment with NaOH. In case of addition of $H_2SO_4$ during organosolv pretreatment of biomass, a fermentation of the organosoluble fraction could be considered as an essential process to increase an efficiency of biomass utilization as well as yield of bioethanol. Precipitates, insoluble by-products in the solvent mixture, were also cficiency oed by diverse analytical methods and revealed that these were typically composed of a lignin moiety regardless of catalyst. According to the results of nuclear magnetic resonance (NMR), Fourier Tcinsform Infrared Spectroscopy (FT-IR) and Gel permeation chromatograp r (GPC), the main components of precipitates seem to be lignin polymers. However, their structures could be slightly modified during pretreatment and mixed with some carbohydrates by chemical bonds and/or physical associations.

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황백나무로부터 항균성분의 분리 및 정제 (Isolation and Purification of Antibacterial Components in Cortex Phellodendri)

  • 김중배;신운섭;권영인;방병호
    • 한국식품영양학회지
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    • 제26권3호
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    • pp.547-552
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    • 2013
  • 황백 껍질은 황벽나무(Phellodendron amurense)의 건조된 수피로부터 얻어진다. 이 수피는 한국의 전통 한약제로서, 설사, 황달, 무릎과 발의 통증, 요도관 및 피부 감염증에 폭넓게 사용되어 왔다. 본 연구는 황벽나무의 메탄올 추출액으로부터 항균성 화합물 분리를 위해 CPC 방법으로 효과적으로 수행하였다. 두 용매의 CPC 최적조성은 n-butanol:acetic acid:water(4:1:5 v/v/v)이었다. 이동상의 유속은 1,000 rpm 회전력에서 상승법으로 분당 3 $m{\ell}$ 속도로 전개시켰다. CPC에서 분리된 분획분은 prep-HPLC로 정제하였다. 분리된 palmatine은 $^1H$, $^{13}C$-NMR, ESI-MS 데이터 분석으로 확인하였다.

Metabolomics Analysis of the Beef Samples with Different Meat Qualities and Tastes

  • Jeong, Jin Young;Kim, Minseok;Ji, Sang-Yun;Baek, Youl-Chang;Lee, Seul;Oh, Young Kyun;Reddy, Kondreddy Eswar;Seo, Hyun-Woo;Cho, Soohyun;Lee, Hyun-Jeong
    • 한국축산식품학회지
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    • 제40권6호
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    • pp.924-937
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    • 2020
  • The purpose of this study was to investigate the meat metabolite profiles related to differences in beef quality attributes (i.e., high-marbled and low-marbled groups) using nuclear magnetic resonance (NMR) spectroscopy. The beef of different marbling scores showed significant differences in water content and fat content. High-marbled meat had mainly higher taste compounds than low-marbled meat. Metabolite analysis showed differences between two marbling groups based on partial least square discriminant analysis (PLS-DA). Metabolites identified by PLS-DA, such as N,N-dimethylglycine, creatine, lactate, carnosine, carnitine, sn-glycero-3-phosphocholine, betaine, glycine, glucose, alanine, tryptophan, methionine, taurine, tyrosine, could be directly linked to marbling groups. Metabolites from variable importance in projection plots were identified and estimated high sensitivity as candidate markers for beef quality attributes. These potential markers were involved in beef taste-related pathways including carbohydrate and amino acid metabolism. Among these metabolites, carnosine, creatine, glucose, and lactate had significantly higher in high-marbled meat compared to low-marbled meat (p<0.05). Therefore, these results will provide an important understanding of the roles of taste-related metabolites in beef quality attributes. Our findings suggest that metabolomics analysis of taste compounds and meat quality may be a powerful method for the discovery of novel biomarkers underlying the quality of beef products.

수산물의 지질에 관한 연구(제1보) 담수산 뱀장어 근육유의 지방산 및 Sterol 조성 (STUDISE ON THE LIPID OF AQUATIC ANIMAL (Part 1) Fatty Acids and Sterols in the Muscle of Eel)

  • 하봉석;정태명;양민석
    • 한국수산과학회지
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    • 제9권3호
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    • pp.203-208
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    • 1976
  • 뱀장어 근육유의 지방질 및 sterol 조성을 GLC로 분석하였고 특히 sterols조성을 IR, NMR, GLC-MS로 동정하여 다음과 같은 결과를 얻었다. 1) 뱀장어 근육유의 지방산 조성은 $C_{18:1}(40.98\%),\;C_{16:0}(23.71\%),\;C_{16:1}(13.37\%)$산이 가장 높은 비율로 함유하며, 다음은 $C_{14:0}(7.19\%),\; C_{18:0}(5.55\%),\;C_{20:1}(1.83\%),\;C_{18:2}(1.42\%)$산 이였고, $C_{18:3}(0.92\%),\;C_{15:0}(0.73\%),\;C_{14:1}(0.50\%)$산은 그 함량이 가장 적었다. 2) sterols 조성은 cholesterol$(96.58\%)$이 대부분이 였고, 24-methylene cholesterol$(3.43\%)$이 있음을 알았다.

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팔라듐 촉매화 비닐 치환 반응을 이용한 Conjugated Dienals의 합성 (Synthesis of Conjugated Dienals by Palladium-Catalyzed Vinyl Substitution Reaction)

  • 이종태;김진일
    • 대한화학회지
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    • 제28권5호
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    • pp.335-341
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    • 1984
  • ${\alpha},{\beta}$-불포화 알데히드의 아세탈은 브롬화 방향족화합물들과 팔라듐 촉매와 트리에틸아민 존재하에서 쉽게 반응하여 방향족의 conjugated enals을 생성하였다. 불포화 아세탈로서 acrolein diethyl acetal과 methacrolein diethyl acetal을 사용하여 이들을 메틸기와 이소프로필기로 치환된 브롬화 방향족화합물들과 $100^{\circ}C$에서 반응시킨 뒤 생성물들을 옥살산 수용액으로 처리하여 방향족의 conjugated enals를 합성하였다. o-bromotoluene과 methacrolein diethyl acetal과의 반응을 제외하고는 모두 60% 이상의 좋은 수득율을 얻을 수 있었으며 생성물의 구조는 proton NMR과 IR스펙트럼으로 확인하였다. 3-bromopropenal dimethyl acetal 및 (E)-3-bromo-2-methylpropenal diethyl acetal을 할로겐화 비닐화합물의 반응 부위로 하고 1-알켄과 ethyl acrylate등을 올레핀 반응 부위로 하는 반응물들의 역조합(reverse combination)에 의하여 지방족의 2,4-dienals를 50% 이상의 수득율로 합성 할 수 있다.

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약물방출시스템 적용을 위한 락타이드/히아루론산 고분자 막의 제조 (Synthesis of Lactide/Hyaluronic Acid Polymer Membrane for the Application of Drug Delivery System)

  • 김민수;권지영;정성일
    • 멤브레인
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    • 제15권4호
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    • pp.281-288
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    • 2005
  • 생체 적합성이 우수한 히아루론산과 생분해성이 우수한 폴리 락타이드의 이량체를 결합하여 약물 방출 시스템에 적용할 수 있는 생체 재료를 제조하고자 하였다. 냉동 건조법을 이용하여 히아루론산과 락타이드를 가교제 1-ethyl-3-(3-dimethyl aminopropyl) carbodiimide (EDC)로 가교시켰다. 생성된 막을 핵자기 공명 분광법으로 분석하여 락타이드 반응도와 EDC 반응도를 결정하였다. 히아루론산에 대한 락타이드 몰비, 가교제 농도가 증가할수록 혹은 가교 온도가 감소할수록, 락타이드 반응도가 증가하였으며 팽윤도는 감소하였다. 서로 다른 락타이드 반응도를 가진 막으로 약물 방출 실험을 수행한 결과 락타이드 반응도가 증가하면 약물 방출 속도가 감소하는 경향을 보였다. 또 친수성이 다른 여러 가지 약물로 약물 방출 실험을 수행한 결과 친수성이 우수한 약물일수록 서서히 방출되었다.

Swallow-Tail Terrylene Bisimide 적색 유기 형광체 제조 및 특성 연구 (Preparation and Characterization of Swallow-Tail Terrylene Bisimide as Organic Phosphor)

  • 정성봉;정연태
    • 한국전기전자재료학회논문지
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    • 제33권3호
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    • pp.194-200
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    • 2020
  • Perylene bisimide derivatives are developed for red organic phosphor because of their advantages, such as excellent luminous efficiency and high thermal stability. Despite these advantages, they have poor solubility characteristics in organic solvents and short emission wavelength as red organic phosphor for hybrid light-emitting diodes (LEDs). In this study, we prepared terrylene bisimide using a coupling reaction and swallow-tail imide group, which has excellent solubility. The structures and properties of swallow-tail terrylene bisimide (9C) were analyzed using 1H-nuclear magnetic resonance (1H-NMR), Fourier-transform infrared (FT-IR), UV/Vis spectroscopy, and thermal gravimetric analysis (TGA). The maximum absorption wavelength of (9C) in the UV/Vis spectrum was 647 nm, and the maximum emission wavelength was 676 nm. In the TGA, (9C) demonstrated good thermal stability with less than 5 wt% weight loss up to 415℃. In the solubility test, (9C) has a good solubility of more than 5 wt% in chloroform and dichloromethane. When the compounds (9C) were mixed with PMMA (polymethly methacrylate), the films showed peaks at 680 nm in the PL spectra. The results verify the suitability of (9C) as a red organic phosphor for hybrid LEDs.

Phenolic Compounds from the Fruit Body of Phellinus linteus Increase Alkaline Phosphatase (ALP) Activity of Human Osteoblast-like Cells

  • Lyu, Ha-Na;Lee, Dae-Young;Kim, Dong-Hyun;Yoo, Jong-Su;Lee, Min-Kyung;Kim, In-Ho;Baek, Nam-In
    • Food Science and Biotechnology
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    • 제17권6호
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    • pp.1214-1220
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    • 2008
  • Secondary metabolites from the fruit body of Phellinus linteus were evaluated for their proliferative effect on human osteoblast-like cells. 3-[4,5-Dimethylthiazole-2-y1]-2,5-diphenyl-tetraxolium bromide (MTT) assay and alkaline phosphatase (ALP) activity assay were used to assess the effect those isolates on the human osteoblast-like cell line (Saos-2). Activity-guided fractionation led to the isolation of ALP-activating phenolic compounds through the extraction of P. linteus, solvent partitioning, and repeated silica gel and octadecyl silica gel (ODS) column chromatographic separations. From the result of spectroscopic data including nuclear magnetic resonance (NMR), mass spectrometry (MS), and infrared spectroscopy (IR), the chemical structures of the compounds were determined as 4-(4-hydroxyphenyl)-3-buten-2-one(1), 2-(3',4'-dihydroxyphenyl)-1,3-benzodioxole-5-aldehyde (2), 4-(3,4-dihydroxyphenyl)-3-buten-2-one (3), 3,4-dihydroxybenzaldehyde (4), and protocatechuic acid methyl ester (5), respectively. This study reports the first isolation of compounds 1-3 and 5 from P. linteus. In addition, all phenolic compounds stimulated proliferation of the osteoblast-like cells and increased their ALP activity in a dose-dependent manner ($10^{-8}$ to $10^{-1}\;mg/mL$). The present data demonstrate that phenolic compounds in P. linteus stimulated mineralization in bone formation caused by osteoporosis. The bone-formation effect of P. linteus seems to be mediated, at least partly, by the stimulating effect of the phenolic compounds on the growth of osteoblasts.

소수성의 이미다졸리움 이온성 액체 합성과 이들의 물리화학적 특성 조사 (Synthesis of Hydrophobic Imidazolium Ionic Liquids and Studies of Their Physiochemical Properties)

  • 무함마드 살만;이수영;이혜진
    • 공업화학
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    • 제32권3호
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    • pp.277-282
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    • 2021
  • 본 연구에서는 PF6를 음이온으로 하며, 이미다졸리움 계열의 양이온을 변화시키면서 2종의 소수성을 띠는 이온성 액체 전해질을 합성하였다. 합성한 이온성 액체는 1-benzyl-3-butylimidazolium hexafluorophosphate [BzBIM]PF6와 1-pentyl-3-butylimidazolium hexafluorophosphate [PBIM]PF6이며 이들 각각의 구조는 푸에리에 변환 적외선 분광기와 핵자기공명 분광기를 이용하여 분석하였다. 이와 함께, 합성한 이온성 액체 전해질의 물리적(점도, 이온전도도, 열적 안정성) 및 전기화학적 특성을 조사하고 비교 분석하였다. 그 결과, [BzBIM]PF6의 경우 [PBIM]PF6와 다르게 이미다졸리움 양이온에 π-π 분자 간 결합이 강하게 존재하는 벤질링 기능기를 가지고 있어서 열적 및 전기화학적 특성에서 더 우세한 안정성을 보여주었다.