• 한국응용약물학회:학술대회논문집
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• 한국응용약물학회 1994년도 춘계학술대회 and 제3회 신약개발 연구발표회
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• pp.263-263
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• 1994

Annexin I is a member of the in family of calcium dependent phospholipid banding proteins and is an in vitro phospholipase $A_2$ (PLA$_2$) inhibitor. The mechanism of PLA$_2$ inhibition by annexin I is still ambiguous. The structure of annexin I was studied at the atomic level by using nuclear magnetic resonance (NMR), circular dichrotsm (CD) and fluorescence spectroscopy. Recombinant human annexin I and N-terminally truncated annexin I (1-31 deleted: d-annexin I) were purified and their NMR spectra were compared. The NMR spectra of the two were similar. When $Ca^{2+}$ ion added to annexin I ad d-annexin I, peak broadening occurred, but no significant spectroscopic change was observed. When porcine pancreatic PLA$_2$ was added to deuterium labeled annexin I, an interaction of annexin I with PLA$_2$ was observed as indicated by the disappearance and shift of several peaks in the NMR spectrum. This result supports a protein-protein interaction mechanism for PLA$_2$ inhibition by annexin I.I.

• Bulletin of the Korean Chemical Society
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• 제20권10호
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• pp.1145-1148
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• 1999

1H NMR spectra of methyl-, ethyl-, propyl-, isopropyl-, butyl-, N-methylethyl-, N-methylpropyl-, and N-methylisopropylamine coordinated to the paramagnetic 11-tungstocobalto(II)silicate anion (SiW11Co) in dimethylsulfoxide-d6 or dimethylformamide-d7 are reported. For these complexes the ligand exchange is slow on the NMR time scale and pure 1H NMR signals have been observed at room temperature. No complex is detected in D2O. From the pseudocontact shifts of the CH2 and CH3 groups in ethylamine the energy of the gauche conformers with respect to the anti conformer is estimated. Two diastereotopic protons in the CH2 group of N-methylethylamine have quite different chemical shifts especially at low temperatures (e.g. 48.5 vs. 19.4 ppm at -10℃). This may be attributed mainly to the different positions of the two protons in the most stable (gauche) conformer.

• Archives of Pharmacal Research
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• 제13권3호
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• pp.246-251
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• 1990

Intermolecular interaction between barbiturates and membrane components such as phospholipid and cholesterol were investigated on $^1$H-NMR spectra and infrared spectra. According to previous reports, barbiturates interacted with phospholipid through intermolecular hydrogen bonds. We also investigated thi observation using dipalmitoyl-phosphatidylcholine (DPPC) as phospholipid in deuterochloroform, and characterized quantitatively. Also, the observed drug could interact with cholesterol which is one of the major components of biomembranes through hydrogen bonds. It was the carbonyl groups of barbiturate and the hydroxyl group of cholesterol that formed hydrogen bond complex. In addition to spectroscopic studies, we investigated the direct effect of phenobarbital on lipid multibilayer vesicles, whose compositions were varied, by calorimetric method. Phenobarbital caused a reduction in the temperature of phase transition of vesicles. These studies may provided a basis for interpreting the mode of action of barbiturates.

• Bulletin of the Korean Chemical Society
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• 제20권10호
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• pp.1205-1208
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• 1999

27Al NMR chemical shielding, quadrupolar coupling, and dipolar coupling interactions for corundum (α-Al2O3) are determined from the single-crystal 27 Al NMR spectra according to the rotation about three orthogonal axis. 27 Al NMR parameters obtained in this work with high accuracy are as follows: δiso = 7.4(4) ppm, QCC = 2.30(4) MHz, h = 0.08(3), and R = 2.0(3) kHz. This work appears to be the first NMR measurement of an aluminum-aluminum dipolar coupling interaction in α-Al2O3 crystals.

• 농업과학연구
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• 제35권1호
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• pp.11-17
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• 2008

가시오가피를 실온에서 petroleum ether로 추출한 polyacetylene의 동정하기 위하여 TLC, HPLC, UV spectrum, IR, NMR로 수행하였다. TLC에 전개시킨 결과, polyacetylene 표준품과 동일한 band가 fraction 5에서 확인되었으며, HPLC에서 fraction 5를 분리시킨 결과 retention time이 4.40, 5.36, 6.40분이었다. 이를 UV spectrum에서 확인한 결과, 6.40분의 peak(compound 3)에서 polyacetylenes의 파장인 231.0nm, 239.0nm, 257.0nm을 나타내었다. IR spetrum에서 triple bond $2256cm^{-1}$과 double bond $1654cm^{-1}$의 전형적인 peak를 나타내었으며, $^{13}C$-NMR(400MHz, $CDCl_3$)에서 polyacetylenes 전형적인 64.0, 71.2, 74.2, 80.2ppm은 2개의 triple bond에 의한 peak와 121.89, 133.0ppm에서 internal double bond로 결합된 2개의 peak를 확인 할 수 있었다.

• 공업화학
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• 제23권6호
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• pp.539-545
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• 2012

전자를 끌어당기는 benzotriazole을 vinylene으로 thiophene과 연결한 3-(2-benzo-triazolovinyl)thiophene (BVT)을 합성하고, FT-IR 및 $^1H$-NMR, $^{13}C$-NMR, 2D hetero-cosy spectra로 구조분석을 하였다. 합성한 BVT와 3-octylthiophene (OT)을 공중합 하였다. 공중합체들은 수평균 분자량 12000 (PDI 2.67)과 15000 (PDI 2.55)을 나타내었으며, THF, TCE와 chloroform 등의 유기용매에 잘 용해되었다. 공중합체들의 BVT와 OT의 공중합된 비율은 $^1H$-NMR spectra에 의하여 BVT : OT = 1 : 1.8과 1 : 2.8 (mol/mol)로 확인되었다. 파장 470 nm와 465 nm에서 UV-vis 최대 흡수를 나타내었고, photoluminescence (PL)는 각각 ${\lambda}_{max}$ = 662 nm와 641 nm로 나타나 적색계로 관찰되었다. 공중합체의 band gap은 각각 1.96 eV, 2.02 eV로 poly(3-octylthiophene)보다 더 증가하였다. 또한, poly(3-octylthiophene)에 비해서 HOMO 에너지 준위는 모두 낮아졌으나, LUMO 에너지 준위는 모두 높아졌다.

• 한국자기공명학회논문지
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• 제25권4호
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• pp.58-63
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• 2021

Apolipoprotein B-100 (apo B-100), the main protein component that makes up LDL (Low density lipoprotein), consists of 4,536 amino acids and serves to combine with the LDL receptor. The oxidized LDL peptides by malondialdehyde (MDA) or acetylation in vivo act as immunoglobulin (Ig) antigens and peptide groups were classified into 7 peptide groups with subsequent 20 amino acids (P1-P302). The biomimetic peptide P143 (IALDD AKINF NEKLS QLQTY) out of C-group peptides carrying the highest value of IgG antigens were selected for structural studies that may provide antigen specificity. Experimental results show that P143 has β-sheet in Ile[1]-Asn[9] and α-helice in Gln[16]-Tyr[20] structure. Homonuclear 2D-NMR (COSY, TOCSY, NOESY) experiments were carried out for NMR signal assignments and structure determination for P143. On the basis of these completely assigned NMR spectra and proton distance information, distance geometry (DG) and molecular dynamic (MD) were carried out to determine the structures of P143. The proposed structure was selected by comparisons between experimental NOE spectra and back-calculated 2D NOE results from determined structure showing acceptable agreement. The total Root-Mean-Square-Deviation (RMSD) value of P143 obtained upon superposition of all atoms were in the set range. The solution state P143 has a mixed structure of pseudo α-helix and β-turn(Phe[10] to Glu[12]). These results are well consistent with calculated structure from experimental data of NOE spectra. Structural studies based on NMR may contribute to the prevent oxidation studies of atherosclerosis and observed conformational characteristics of apo B-100 in LDL using monoclonal antibodies.

• 분석과학
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• 제7권2호
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• pp.213-224
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• 1994

선택적으로 중수소를 치환시킨 싸이클로옥타논의 여러 동위원소 이성질체들을 합성하였다. 고유동위원소 효과에 의해 영향을 받는 $^{13}C$ NMR 화학적 이동값들을 각 이성질체에 대해 저온에서 계통적으로 관찰하였다. 특히 싸이클로옥타논이 선호하는 안정한 형태 이성질체인 클 boat-chair 형과 연관시켜 이 효과들을 논의하였다.

• 한국신재생에너지학회:학술대회논문집
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• 한국신재생에너지학회 2005년도 춘계학술대회
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• pp.615-617
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• 2005

[ $^{13}C$ ] NMR spectra were obtained for pure $CH_4$ hydrate in order to identify hydrate structure and cage occupancy of guest molecule. The NMR technique can provide both qualitative and quantitative hydrate characteristics. The moles of methane captured into pure $CH_4$ hydrate per mole of water were found to be similar to the full occupancy value. The overall results drawn from this study can be usefully applied to storage and transportation of natural gas.

• 대한화학회지
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• 제50권3호
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• pp.183-189
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• 2006

초음파를 이용한 응축 반응을 이용하여 다양한 치환기가 붙은 4-methoxy-1-naphthyl ketone화합물들을 90% 이상의 높은 수율로 합성하였으며, 생성된 화합물물들을 미세 분석법, IR, 1H, 13C NMR 분석법 등을 이용하여 확인하였다. IR 스펙트럼에서 s-cis와 s-trans C=O stretching 모드를 확인하였으며, NMR 데이터로부터 에틸렌의 탄소와 수소에 대한 chemical shift를 확인하였다. 이러한 분광데이터를 이용하여 여러 분자들에 대한 Hammet 치환기 상수 값 들을 얻을 수 있었으며, 이들로부터 가용매 분해반응에 미치는 치환기 효과를 해석할 수 있었다.