• Bulletin of the Korean Chemical Society
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• 제13권3호
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• pp.230-235
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• 1992

The conformational analysis has been done for catecholamines (dopamine, norepinephrine, and epinephrine) in the cationic and di-anionic states. The species responsible for adsorption on silver metal surface is anionic deprotonated at hydroxyl groups of catechol moiety, i.e., di-anionic states of catecholamines. This was deduced from Fourier-transform Raman spectra of sodium salts of catecholamines. High resolution proton NMR (400 MHz) spectra of catecholamines in basic and neutral $D_2O$ solution show that the conformations of norepinephrine and epinephrine in the di-anionic states are preferred in gauche, but not for dopamine in the di-anionic state. However the energy difference between trans and gauche of catecholamines in the protonated cationic states is small enough to rotate freely through C-C bond in ethylamine moiety. The conformational calculations using an empirical potential function and the hydration shell model (a program CONBIO) show consistent with above experimental results. The calculations suggest that the species of catecholamines adsorbed on silver metal surface would be in favor of the gauche conformations.

• 한국응용과학기술학회지
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• 제22권4호
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• pp.323-331
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• 2005

Fatty acid compositions of the seed oils of P. schinseng, A. continentalis and A. sessiliflorus, were analyzed by gas chromatography (GC) equipped with a capillary column. A large unusual peak was observed just before the peak corresponding to oleic acid $(cis-9-C_{18:1})$. This unknown fatty acid was isolated by silver ion chromatography and then derivatized into the picolinyl ester. The mass spectrum of the picolinyl ester showed molecular ion at m/z=373 with other diagnostic ions such as m/z=178, 218, 232, 246, 274, 288, 302 and 344. Characteristic absorption peaks at $720\;cm^{-1}$, $1640\;cm^{-1}$ and $3010\;cm^{-1}$ in IR spectrum indicated the presence of cis-configurational double bond in the molecule. The $^1H-NMR$ spectrum of this acid gave two quintets centered at ${\delta}1.638$ (2H, C-3) and ${\delta}1.377$ (2H, C-4), and two multiplets centered at ${\delta}2.022{\sim}2.047$ (2H, C-5) and ${\delta}2.000{\sim}2.022$ (2H, C-8), and multiplet signals of olefinic protons centered at ${\delta}5.3015{\sim}5.3426$ (C-6, J=9.5 Hz) and ${\delta}\;5.3465{\sim}5.3877$ (C-7, J=9.5 Hz). The $^13C-NMR$ spectrum showed 18 carbon resonance signals including an overlapped signal at ${\delta}29.7002$ for C-12 and ${\delta}29.6520$ for C-13 (or they can be reversed), and other highly resolved signals at ${\delta}33.950$, ${\delta}24.558$, ${\delta}26.773$ and ${\delta}27.205$ due to C-2, C-3, C-5 and C-8 of a ${\Delta}^6-octadecenoic$ acid, respectively. From analysis results this unknown fatty acid could be identified as cis-6-octadecenoic acid. The seed oils of P. schinseng and A. sessiliflorus contained petroselinic acid (59.7%, 56.0%), oleic acid (18.3%, 6.1%) and linoleic acid (16.2%, 30.4%) with small amount of palmitic acid (3.0%, 3.1%) while the seed oil of A. continentalis comprised mainly oleic acid (30.2%), petroselinic acid (29.0%), linoleic acid (24.1%) and palmitic acid (13.1%).

• Macromolecular Research
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• 제13권6호
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• pp.491-498
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• 2005

Fluorene-containing, spiro-type, conjugated polymers were synthesized via the cyclopolymerization of dipropargylfluorenes (2-substituted, X=H, Br, Ac, $ NO_{2}$) with various transition metal catalysts. The polymerization of dipropargylfluorenes proceeded well using Mo-based catalysts to give a high polymer yield. The catalytic activities of the Mo-based catalysts were found to be more effective than those of W-based catalysts. The palladium (II) chloride also increased the polymer yield of the polymerization. The polymer structure of poly(dipropargylfluorene)s was characterized by such instrumental methods as NMR ($^{1}H_{-}$, $^{13}C_{-}$), IR, UV-visible spectroscopies, and elemental analysis as having the conjugated polymer backbone bearing fluorene moieties. The $^{13}C_{-}$NMR spectral data on the quaternary carbon atoms in polymers indicated that the conjugated cyclopolymers have the six-membered rings majorly. The poly(dipropargylfluorene) derivatives were completely soluble in halogenated and aromatic hydrocarbons such as methylene chloride, chloroform, benzene, toluene, and chlorobenzene. The poly(dipropargylfluorene) derivatives were thermally more stable than poly(dipropargylfluorene) itself, and X-ray diffraction analyses revealed that the polymers are mostly amorphous. The photoluminescence peaks of the polymers were observed at about 457-491 nm, depending on the substituents of fluorene moieties.

• 한국미생물·생명공학회지
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• 제38권1호
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• pp.105-111
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• 2010

소목은 전통적으로 타박상, 염증 등의 질병치료를 위해 민간의학에서 오래 동안 사용되어 온 한약재야다. 소목의 섬재로부터 항균효과를 조사하기 위하여 MeOH 추출에 의한 hexane, $CHCl_3$, EtOAc, n-BuOH, MeOH 및 $H_2O$ 분획을 얻었다. 분획 시료 중 3.94%의 가장 높은 수율의 EtOAc 분획이 조사된 인채 병원성 세균에 대해 가장 강한 항균활성 나타냈다. 또한 EtOAc 분획의 항균활성은 Gram (-) 균주 보다 Gram (+) 균주에 더 효과적이며, Gram (-) 균주에 대해서는 세균에 따른 항균활성의 차이를 보였다. EtOAc 분획은 silica gel adsorption column chromatography 및 Sephadex LH-20을 이용하여 분리하였으며 수득한 주요 성분은 채결정을 통하여 얻어진 단일물질을 HPLC를 이용하여 순도를 측정하였다. 300g의 C. sappan으로부터 3.94%의 EtOAc 분획을 얻었으며 EtOAc분획물은 분석한 결과 10 mg에는 1.67 mg의 brazilin을 포함하였다. 분리된 활성울질은 짧은 황색 결정의 단일 화합물로 MS에 의해 분자량이 285로 나타났으며, $^1H$-NMR, $^{13}C$-NMR에 의한 구조분석으로 brazilin($C_{16}H_{14}O_5$을 동정하였다. 이 같은 결과는 소목의 MeOH 추출에 의한 EtOAc 분획에 존재하는 brazilin이 S. aureus와 같은 인체 병원성 Gram (+) 균주에 대한 생약치료제로 활용이 가능할 것을 시사한다.

• 한국미생물·생명공학회지
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• 제30권1호
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• pp.21-25
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• 2002

토양으로부터 분리한 Bacillus sp. YJ-63으로부터 항진균성 항생물질을 분리하여 그 구조를 분석한 결과는 다음과 같다. 항생물질은 7개의 $\alpha$-amino acid와 1개의 $\beta$-amino acid가 결합한 환상구조를 가지는 iturin E 계에 속하며 특히. $\beta$-amino acid의 methylene 수가 기존의 iturin E 보다 더 많은 것으로 나타났다.

• Bulletin of the Korean Chemical Society
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• 제27권6호
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• pp.893-898
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• 2006

Novel bis- and tris-crown ethers were synthesized from 1-aza and diaza-crown ethers with 2-acryloyloxy-methyl crown ethers through Michael addition. The synthesized bis- and tris-crown ethers were characterized by their elemental analyses, $^1H$-NMR, $^{13}C$-NMR, mass spectra, IR spectra, respectively. The complexation behavior of the bis- and tris-crown ethers with $Li^+$, $Na^+$, $Na^+$, $Rb^+$, $Cs^+$ was examined by $^1H$-NMR, FAB mass, and UV spectrometry.

• 한국미생물·생명공학회지
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• 제22권2호
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• pp.169-174
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• 1994

Antitumor antibiotic HS-1 was purified from the culture broth of a streptomyces floridae SHS-1372 which had been isolated from soil, by solvent extraction, silica gel column chromatography and gel filtration. It was confirmed that HS-1 was active against gram positive bacteria and cancer cells(K562, P388, MCF-7, HT-29). Through the analysis of UV spectrum, melting point, IR spectrum, FAB-MS, $_{1}$H-NMR, $_{13}$C-NMR, 2D-NMR spectra, HS-1 could be identified sa the actinomycin X$_{2}$ antibiotics containing actinocine chromophore and peptides consisted of threonine, proline, methylvaline, sarcosine, D-valine and 4-ketoproline.

• 한국생물공학회:학술대회논문집
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• 한국생물공학회 2000년도 추계학술발표대회 및 bio-venture fair
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• pp.626-629
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• 2000

The Pseudomonas aeruginosa BYK-2(KCTC 18012p) produced three kinds of glycolipids on olive oil as a substrate and purified two types of major glycolipids(Rf=0.48, BS-1; Rf=0.65, BS-2) using silica gel chromatography, TLC, HPLC, etc. From the analysis of the chemical structure, the glycolipid of BS-1 was estimated as rhamnolipid($2-O-{\alpha}-L-rhamnopyranosyl- {\alpha}-L-rhamnopyranosyl-{\beta}-hydroxyldecanoyl-{\beta}-hydroxydecanoic$ acid; M.W. 650) and BS-2 was detected as rhamnolipid methyl ester($2-O-{\alpha}-L-rhamnopyranosyl-{\alpha}-L-rhamnopyranosyl-{\beta}-hydroxyldecanoyl-{\beta}-hydroxydecanoic$ acid methyl ester; M.W. 664) by FT-IR, FAB Mass spectrometry, $^1H-NMR$, $^{13}C$ FT-NMR, DEPT, 2D-NMR (TOCSY, RELAY, NOESY, HSQC, HMBC). In particular, It was found that a marine bacterium Pseudomonas aeruginosa BYK-2(KCTC 18012P) remarkably produced rhamnolipid and rhamnolipid methyl ester simultaneously.

• Bulletin of the Korean Chemical Society
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• 제31권4호
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• pp.815-818
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• 2010

Free base meso-tetraarylporphyrins ($H_2T(X)PP$) react with tellurium(IV) chloride ($TeCl_4$) in mild conditions for formation sandwich intermediate sitting-atop (i-SAT) complexes, [$TeCl_4(H_2T(X)PP)_2$]. $^1H$ NMR, $^{13}C$ NMR, UV-vis, FT-IR and elemental analysis were used for characterization of the products. In the proposed structure of the i-SAT complexes, four pyrroles of each porphyrin ring are tilted alternatively up and down and this appropriates suitable orientation of lone pairs of two pyrrolenine nitrogens for electron donation to a tellurium center. $^1H$ NMR and FT-IR results showed that in the produced complex, hydrogen atoms of porphyrin macrocycles remained on the pyrrole nitrogens.

• 한국자기공명학회논문지
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• 제10권1호
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• pp.115-125
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• 2006

Hippuryl-L-histidyl-L-leucine(HHL) is widely used as a substrate of angiotensin converting enzyme(ACE) cleaving the neurotransmitter angiotensin(I) to the octapeptide angiotensin(II). The structure of the substrate molecules should provide information regarding the geometric requirements of the ACE active site. For the purpose of determination of in vivo reaction, metallo(Cu, Zn)-HHL complexes were synthesized and the degree of complex formation were identified by MALDITOF, ESI mass spectrometric analysis. Tn addition, the pH-dependent species distribution curves were obtained by potentiometric titration. Nitrogen atoms of imidazole ring and oxygen atom of caboxylate groups in the peptide chain were observed to be participated in the metal complex formation. After purification of complexes further structural characterization were made by utilizing UV-Vis, electrochemical methods and NMR. Complete NMR signal assignments were carried out by using 2D-spectrum techniques COSY, TOCSY, NOESY, HETCOR. A complex that two imidazole and carboxylate groups are asymmetrically participating to coordination mode was predicted to the solution-state structure of $Cu(II)-HHL_2$ based on $^{13}C-NMR$ signal assignment and NOE information.