• 한국염색가공학회지
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• 제2권2호
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• pp.1-6
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• 1990

In order to investigate the fine structural changes of poly (ethylene terephthalate) film by hydrazinolysis, PET was treated with hydrazine hydrate in methanol at $30^{\circ}C$ for various times. Initially apparent crystallite size and degree of orientation are increased and then, gradually decreased with hydrazinolysis. According to thermoluminescence measurement, trap site decreased by dissolution and then gradually increased with growth of defect in structure. Maximum peak temperature of tan and dynamic loss modulus E" upon hydrazinolysis shifted to the lower temperature in the progress of hydrazinolysis.ysis.

• Natural Product Sciences
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• 제3권2호
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• pp.89-99
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• 1997

Aminolysis, hydrazinolysis and alkylation of 4-methoxy and 4,9-dimethoxy-6-cyano-7-thione-5-methyl-7H furo [3,2-g] [1] benzopyridine (1 a-b) yielded 7N-substituted furobenzopyridine derivatives (2 a-e or the possible isomers 3 a-e and 4 a-b), (5 a,b and 6 a,b) and the ester (8 a,b). Hydrolysis of (la) with acetic acid gave the corresponding pyridone derivatives (7). Furobenzopyridinyl-7-thioacetyl hydrazide (9 a,b) have been prepared via alkylation of furobenzopyridine thione (1 a-b) with ethyl chloroacetate followed by condensation with hydrazine hydrate. Schiff base (11) was prepared by reacting (9a) with p. N,N-dimethyl aminobenzaldehyde in boiling ethanol. Treatment of (8a) with anthranilic acid gave the corresponding 7-substituted-4H-3,1-benzoxazine-4-one (10). We found that compound (11) increased bleeding, coagulating time, the total count of white blood cells, blood glucose level (cause hyperglycemia), enzymes (GOT, GPT) activities, concentration of urea and creatinine. On the other hand it decreased red blood cells number, haemoglobin content and haematocrite value.

• Bulletin of the Korean Chemical Society
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• 제35권8호
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• pp.2271-2276
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• 2014

Second-order rate constants ($k_N$) have been measured spectrophotometrically for the reaction of 4-chloro-2-nitrophenyl X-substituted-benzoates (6a-6h) with a series of primary amines including hydrazine in 80 mol % $H_2O$/20 mol % DMSO at $25.0^{\circ}C$. The Br${\o}$nsted-type plot for the reaction of 4-chloro-2-nitrophenyl benzoate (6d) is linear with ${\beta}_{nuc}$ = 0.74 when hydrazine is excluded from the correlation. Such a linear Br${\o}$nsted-type plot is typical for reactions reported previously to proceed through a stepwise mechanism in which expulsion of the leaving group occurs in the rate-determining step (RDS). The Hammett plots for the reactions of 6a-6h with hydrazine and glycylglycine are nonlinear. In contrast, the Yukawa-Tsuno plots exhibit excellent linear correlations with ${\rho}_X$ = 1.29-1.45 and r = 0.53-0.56, indicating that the nonlinear Hammett plots are not due to a change in RDS but are caused by resonance stabilization of the substrates possessing an electron-donating group (EDG). Hydrazine is ca. 47-93 times more reactive than similarly basic glycylglycine toward 6a-6h (e.g., the ${\alpha}$-effect). The ${\alpha}$-effect increases as the substituent X in the benzoyl moiety becomes a stronger electron-withdrawing group (EWG), indicating that destabilization of the ground state (GS) of hydrazine through the repulsion between the nonbonding electron pairs on the two N atoms is not solely responsible for the substituent-dependent ${\alpha}$-effect. Stabilization of transition state (TS) through five-membered cyclic TSs, which would increase the electrophilicity of the reaction center or the nucleofugality of the leaving group, contributes to the ${\alpha}$-effect observed in this study.

• Bulletin of the Korean Chemical Society
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• 제29권7호
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• pp.1315-1319
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• 2008

A trisaccharide, 6d-Altro-Hepp$\alpha$ (1$\rightarrow$3) GlcNAc$\beta$ (1$\rightarrow$3) Gal$\alpha$ (1$\rightarrow$$OCH_2CH_2N_3$, as an O-antigenic repeating unit of Campylobacter jejuni serotypes O:23 and O:36, was synthesized. Coupling of the 6d-altro-Hepp$\alpha$ (1$\rightarrow$3) GlcNAc$\beta$ (1$\rightarrow$SEt donor with Gal$\alpha$ (1${\rightarrow}OCH_2CH_2Cl$ acceptor in the presence of NIS-TfOH promoter afforded the trisaccharide having the $\beta$ (1$\rightarrow$3) Gal linkage. $\beta$ -Stereospecificity and the desired regioselectivity for the 3-OH Gal are obtained. Subsequent hydrogenation, acetylation, azide displacement, hydrazinolysis, Nacetylation, and finally deacetylation furnished the title trisaccharide hapten for further glycoconjugation.

• 한국섬유공학회:학술대회논문집
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• 한국섬유공학회 1996년도 춘계학술발표회 논문집
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• pp.158-161
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• 1996

Microfibers of Poly(ethylene terephthalate)(PET)/Nylon 6 (P/N) was heat set at 170C in a fixed state and then treated with hydrazine at 30C for 5, 10, 15, 20, 30 and 40 h. Weight loss from the hydrazine treatment increased according to the hydrazine concentration(Fig.1). In order to investigate in detail the effect of the electrostatic attraction between the dye anion and hydrazide groups in cooperated by hydrazinolysis, -potential of P/N fiber was measured by streaming potential method. The surface charge density, o, of the fiber was evaluated from the -potential.

• Biotechnology and Bioprocess Engineering:BBE
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• 제5권2호
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• pp.136-140
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• 2000

A sensitive and quantiative method for the structural analysis of oligosaccharide was established for the glycoform analysis of glconproproteins. Inthis study, n-linked oligosaccharides of human IgG and bovine transferin were analyzed for the evaluation of the methydrate moiety ofthe method. Chrbohydrate moiety of glycoprotein was relased by hydrazinolysis and purified by paper chromatography. The oligosaccharides were labeled with a fluorescent bye, 2-aminobenzamide, for the enhancement of detection sensitivity. sialylated (acidic) oligosaccharides were separated from neutral oligosaccharide by employing a strong anion-exchange column(MonoQ) followed by the treatment with sialidase. Enzymatically desiayated fractions and neutral fractions of oligosaccharides were applied to normal-phase HPLC to resolve the peaks according to glucose unit (GU). The structure of separated molecules was further determined by sequential digestion with exoglycosidases. As a result, disialylated biantennary complextype oligosaccharide was found to be a major sugar chain in bovine transferrin (63%). In human IgG, core fucosylated asialobiantennary complex oligosaccharides were dominant. These results coincided well with reported results.

• Journal of Dairy Science and Biotechnology
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• 제21권2호
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• pp.138-147
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• 2003

We here analyzed and proposed the structures of the N-linked sugar chains of PAS-7 from bovine milk fat globule membrane. The N-linked sugar chains were liberated from PAS-7 by hydrazinolysis and, after modifying the reducing ends with 2-aminopyridine (PA), were separated into one neutral (7N,55%) and two acidic (7M mono-, 43%; 7D, di-, 2%) sugar chain roups. The latter were converted into neutral groups (7MN and 7DN) by sialidase digestion. The structure of each of these PA-neutral sugar chains was determined by sugar analysis, sequential exoglycosidase digestion, partial acetolysis, and 1H-NMR spectroscopy. The results show that the 10 sugar chains were of the biantennary complex type with and without fucose. The structure of 7N2A one of the major sugar chains, was proposed as; [structure: see text] A structural comparison between PAS-6 and -7 indicated that although they shared the same protein core, their sugar moiety was markedly different, involving the existence of a different pathway during the post-transcriptional modification.

• 한국축산식품학회지
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• 제21권4호
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• pp.367-373
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• 2001

MFGM 당단백질의 하나인 PAS-7을 GPC 및 affinity chromatography에 의해 정제하여 2-AB로 형광 표식한 후, anion-exchange column 및 reversed-phase column을 이용해 5개의 성분을 분리하였다. 그 중 가장 상대량이 많은 성분 e에 대하여 RAAM2000을 이용한 당쇄구조 해석을 실시하여, 성분 e는 RAAM2000 GPC에 의하여 4개의 성분으로 분리되어 각각 calibration standard 12.10, 8.88, 5.84 및 4.86GU의 용출위치에 검출되었다. 이 용출위치와 당쇄구조는 livrary의 component-7457과 일치하며, 12.2GU의 크기로 분자량은 1788로 판단되며 library의 당쇄와 약 85%의 확률로 일치했다. 그 결과 성분 e의 당쇄구조는 환원말단에 $\alpha$1-6결합된 fucose를 1개 함유하며, core부분의 비환원말단에 N-acetyllactosamine branch를 2개 함유한 전형적인 biantennary 당쇄구조인 것으로 추축되어, 이전 HPLC, acetolysis, sequential exoglycosidase 소화, NMR분석에 의해 보고된 성분 7N1A의 구조와 일치함으로써, OGS RAAM2000을 이용한 PAS-7의 당쇄구조 해석의 유용성이 증명되었다.

• 대한화학회지
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• 제5권1호
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• pp.38-41
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• 1961

By varying groups on biologically active molecules, it is possible to produce analogues which sometimes inhibit the action of the parent compound. Such is true of taurine(${\beta}$-amino-ethane sulfonic acid)as an analogue of ${\beta}$-alanine and of pantoyl taurine for pantothenic acid. It seemed possible that the sulfonic acid analogues of amino acids built into peptides might possibly produce inhibition of the parent peptide. Tauryl-L-histidine was selected to prepare as an analogue of carnosine(${\beta}$-alanyl-L-histidine). There were several reasons for this choice. Camosine causes a slight contraction of isolated uterine muscle and inhibition of this action can be easily tested. Also, taurine, being a ${\beta}$-amino sulfonic acid, is much more stable than the ${\beta}$-amino sulfonic acids. Phthalyl tauryl-L-histidine methyl ester was prepared by condensing phthalyl tauryl chloride with histidine methyl ester in chloroform. The yields were quite low possibly due to reaction between the acid chloride and the imidazole of histidine. Approximately 50 per cent yield of crude amorphous product was obtained, but upon purification by crystallization they yielded only 25 percent of a pure product. The methyl ester was removed by acid hydrolysis to prevent partial cleavage of the phthalyl group. Crystalline tauryl histidine was then obtained from this acid by removal of the phthalyl group by hydrazinolysis. Tests for inhibition were carried out by comparing the action of camosine on isolated uterine muscle before and after tauryl histidine had been added to the bath surrounding the muscle strip. Only in very high relative concentrations of tauryl histidine was there any demonstrable inhibition.

• Applied Biological Chemistry
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• 제17권2호
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• pp.125-137
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• 1974

Selenomonas ruminantium 균체(菌體)를 TCA로 가열(加熱) 분해(分解)한 후 chloroform : methanol (1 : 3)로 추출(抽出)한 당지질(糖脂質)을 분리(分離)하고 이 당지질(糖脂質)을 acetone가용부분(可溶部分) spot A화합물(化合物)과 acetone불용부분(不溶部分)에서 ether로 다시 가용부분(可溶部分)을 추출(抽出)한 spot B화합물(化合物)의 두 부분(部分)으로 분리(分離)하고 이 두 화합물(化合物)에 대(對)하여 각각(各各) 그 화학구조(化學構造)를 구명(究明)하며 당지질(糖脂質)의 구조(構造)를 추정(推定)한 바 다음과 같은 결과(結果)를 얻었다. 1. 두 화합물(化合物)의 적외선흡수분석결과(赤外線吸收分析結果) spot A는 amino당(糖)에 O-acyl 및 N-acyl지방산(脂肪酸)이 결합(結合)하였으며 spot B는 amino당(糖)에 O-acyl 및 N-acyl지방산(脂肪酸)이 결합(結合)하고 인(燐)을 함유(含有)하고 있음을 알았다. 2. 두 화합물(化合物)을 GLC에 의(依)하여 지방산조성(脂肪酸組成)을 조사(調査)한 바 spot A.B화합물중(化合物中)에 있는 O-acyl 및 N-acyl 지방산(脂肪酸)은 ${\beta}-OH\;C_{13:0}$지방산(脂肪酸)이 대부분(大部分)이 였는데 저급(低級)의 hydroxy지방산(脂肪酸) ${\beta}-OH\;C_{9:0}$도 특이적(特異的)으로 함유(含有)되여 있음을 알았다. 3. 두 화합물(化合物)을 hydrazine분해(分解)를 시킨 결과(結果)를 paper chromatography로 조사(調査)한 바 spot A화합물(化合物)은 glucosamine 이 2분자(分子) 결합(結合)하여 있는 chitobiose와 같은 Rf 치(値)를 나타냈음으로 2분자(分子)의 glucosamine이 결합(結合)됨을 확인(確認)하고 spot B 화합물(化合物)의 낮은 Rf치(値)는 glucosamine에 인(燐)이 결합(結合)되여 있음을 알았다. 4. spotA화합물(化合物)의 산분해물(酸分解物)을 다시 ninbydrine으로 산화분해(酸化分解) 시키면 arabinose만이 생기는 것으로 보아 glucosamine의 amino기(基)는 $C_2$의 위치(位置)에 결합(結合)하여 있음을 알았다. 5. N-acetyl화(化)한 spot A에 $NaBH_4$를 추리(處理)한 결과(結果) glucosamine의 전량(全量)이 반감(半減)하는 것으로 보아 2분자(分子)의 glucosamine이 결합(結合)되여 있는 것을 알 수 있고 Morgan-Elson반응(反應) 및 $NaIO_4$분해(分解)에 의(依)하여 2개(個)의 glucosamine은 1.6결합(結合)임을 확인(確認)하였다. 6. N-acetyl화(化)한 spot A.B화합물(化合物)에 ${\beta}-N-acetyl$ glucosarninidase를 반응(反應)시킨 결과(結果) spot A화합물(化合物)은 100% N-acetyl glucosamine으로 분해(分解)되고 spot B화합물(化合物)은 분해(分解)되지 않았으므로 spot A화합물(化合物)만이 ${\beta}$결합(結合)을 하고 있음을 알았다. 7. $^{32}P$함유(含有) spot B화합물(化合物)에 phosphodiesterase 및 phosphomonoesterase를 작용(作用)시킨 결과(結果) phosphodiesterase는 반응(反應)치 않고 phosphomonoesterase에 의(依)하여 100% $^{32}P$가 유리(遊離)되는 것으로 보아 glucosamine 2분자(分子)에 한계의 인(燐)이 monoester결합(結合)을 하고 있음을 알 수 있다. 8. spot A화합물(化合物)은 glucosaminiyl ${\beta}-1.6-glucosamine$의 결합(結合)을 하였고 O-acyl 및 N-acyl지방산(脂肪酸)이 결합(結合)되여 있으며 주지방산(主脂肪酸)은 ${\beta}-OH\;C_{13:0}$임을 알았다. 9. spot B화합물(化合物)도 glucosaminyl ${\beta}-1.6-glucosamine$의 결합(結合)을 하고 O-acyl 및 N-acyl지방산(脂肪酸)이 결합(結合)되여 있으며 주지방산(主脂肪酸)은 ${\beta}-OH\;C_{13:0}$이나 인(燐)이 monoester결합(結合)을 하고 있는 것이 spot A화합물(化合物)과 특이(特異)함을 알았다.