• BMB Reports
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• 제33권4호
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• pp.312-316
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• 2000

Effects of various nitrogenous compounds on the peroxidative activity of Korean radish (Rophanus sativus L.) isoperoxidase $A_1$ were examined by using anilino substrates, such as dianisidine and phenylenediamine. We also used phenolic substrates such as guaiacol, chlorogenic acid, caffeic acid, ferulic acid and esculetin. The peroxidation of dianisidine was stimulated by adenine and imidazole as much as 5 fold and 11 fold, respectively at pH 8. Moreover, about 4.8 fold and 8 fold stimulation of phenylenediamine peroxidation occurred by adenine and imidazole, respectively at pH 8. The stimulation by adenine and imidazole did not occur at the acidic pH range. The peroxidations of phenolic substrates, such as guaiacol, chlorogenic acid, caffeic acid, ferulic acid and esculetin, were not boosted greatly by any of the nitrogenous compounds tested. Notably, ammonium salt, which has been known for the excellent booster of horseradish peroxidase, did not affect the peroxidation of the Korean radish isoperoxidase $A_1$. The kinetic studies of dianisidine peroxidation with imidazole, as a model of boosting reaction, showed that neither the affinity of imidazole against dianisidine, nor the activation energy of dianisidine peroxidation changed during the activity boosting of isoperoxidase $A_1$.

• International Journal of Industrial Entomology and Biomaterials
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• 제14권2호
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• pp.127-135
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• 2007

Precocious metamorphosis was induced in two popular bivoltine breeds i.e. YB and $NB_4D_2$ by an imidazole compound having anti-juvenile hormone activity. The chemical was administered by feeding treatment with mulberry leaf to freshly moulted (0-6 hrs) IV instar larvae. The dose of the chemical was found to be breed specific being 650 ppm for YB and 500 ppm for $NB_4D_2$. The chemical caused complete skipping up of the fifth instar larvae which is most susceptible to diseases. But IV instar was somewhat prolonged. As a result the total larval period was reduced by 4-5 days. However, some of the rearing and reeling parameters like cocoon yield, cocoon weight, shell weight, shell %, filament length and fecundity were reduced for that particular generation only. The effective rate of rearing (ERR %) was significantly increased in trimoulters during the most unfavourable August - September seed crop season. Number of cocoons / kg and number of male moth were significantly higher in trimoulters. These may be useful for preparation of $multi{\times}bi$ hybrid seed. Fine denier was also found in trimoulter cocoon which is the cause of getting fine silk filament from trimoulter cocoons. Normal mating behaviour and emergence pattern was recorded in trimoulters. Bivoltine trimoulter males also showed competence for mating with multivoltine females. These results suggest the possibility of getting trimoulter males during hot and humid seasons when rearing of bivoltine is almost impossible particularly in Eastern and North Eastern India.

• 대한화학회지
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• 제66권3호
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• pp.194-201
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• 2022

A simple, efficient, and cost-effective method has been employed for the synthesis of 2,4,5-trisubstituted imidazole derivatives (3a-j) containing quinoline substituent at 2^nd position. Title compounds were obtained by multicomponent reaction (MCR), involving aryl substituted 1,2-diketone, quinoline carbaldehyde and ammonium acetate in the presence of acetic acid solvent under mild reaction conditions. The newly synthesized quinoline containing imidazole derivatives were confirmed through FT-IR, ¹H-NMR, ¹³C-NMR and mass spectral analysis. In-vitro microplate alamar blue assay (MABA) to determine the MIC (minimum inhibitory concentration) values against Mycobacterium tuberculosis H37Rv was performed for the synthesized compounds. The synthesized compounds exhibited activity against Mycobacterium tuberculosis and among which compounds, 3d, 3f and 3i showed good activity. The highest activity was showed with compound 3i. The anti-mycobacterial activity results are well correlated with the computational molecular docking analysis, which was performed for the synthesized compounds prior to the evaluation of the activity.

• 접착 및 계면
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• 제8권1호
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• pp.15-27
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• 2007

폴리이미드 필름과 구리의 접착력을 향상시키기 위하여 이온빔과 실란-이미다졸 커플링제를 사용하여 폴리이미드 표면개질을 실시하였다. 실란-이미다졸 커플링제는 구리와의 배위결합을 형성하는 이미다졸 그룹과 실록산 폴리머를 형성하는 메톡시 실란 그룹을 함유한다. 폴리이미드 필름표면은 아르곤/산소 이온빔으로 일차로 처리하여 친수성을 높인 폴리이미드 필름에 커플링제 수용액에 침지하여 폴리이미드 필름 표면에 커플링제를 그라프트시켜 표면개질을 실시하였다. XPS 스펙트럼 분석결과 아르곤/산소 플라즈마 처리는 폴리이미드 표면에 하이드록시 및 카르보닐 그룹과 같은 산소 기능성기를 형성함을 알 수 있었고 폴리이미드 필름 표면에 실란-이미다졸과의 커플링반응에 의하여 표면이 개질되었음을 확인하였다. 이온빔을 사용하여 그라프트된 폴리이미드 필름과 구리와의 접착력은 처리되지 않은 폴리이미드 필름과의 접착력 보다 높은 접착력을 나타내었다. 또한 커플링제로 그라프트된 폴리이미드 필름의 접착력 보다 아르곤/산소의 양자화 이온을 이용하여 개질한 그라프트된 폴리이미드 필름의 시편이 더 높은 접착력을 나타내었다. 구리-폴리이미드 필름의 계면으로부터 박리된 층은 분석결과 완전히 서로 다른 화학적 조성을 나타내었는데 이것으로부터 박리가 접합면의 커플링제 내에서 일어나는 것보다는 폴리이미드와 커플링제의 사이에서 일어남을 확인하였다.

• 한국결정학회지
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• 제12권4호
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• pp.212-215
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• 2001

NaOAC·3H₂O 존재 하에서, manganese nitrate(Mn(NO₃)₂·H₂O )와 imidzole-4,5-dicarboxylic acid(IDCH₂)가 수열반응하여, 실험식 [Mn(IDC)(H₂O)]을 가지는 2차원 배위고분자 합성되었다. 화합물 1의 구조가 분광학적 방법(IR) 및 X-ray 회절법으로 규명되었다. 화합물의 1의 결정학적 자료: 사방정계 공간군 Pbca, a=7.257(5) Å b=13.687(5)Å, c=14.332(6)Å Z=8, R(wR₂)=0.0498(0.0999).

• 대한화학회지
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• 제5권1호
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• pp.33-37
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• 1961

We have shown that carboxy-peptidase destroys the biological activity of angiotensin octa-and deca-peptides. Since Proline occurs as the seventh amino acid from the amino end of the chain and since carboxypeptidase does not cleave proline from a peptid chain, it is evident that the heptapeptid H.asp-arg-val-tyr-ileu-his-pro.OH is formed by this hydrolysis. This peptide must then be biologically inactive. In order to determine whether the phenyl group of the C-terminal amino acid was the necessary requirement for biological activity of the octapeptide, $ala^8$ angiotensin octapeptide(amino acids of peptides numbered from amino end) was synthesized. For this synthesis the four dipeptides were prepared: carbobenzoxy-L-prolyl-L-alanine-P-nitrobenzyl-ester, m.p. $134-135^{\circ}C,$ carbobenzoxy-L-isoleucyl-imidazole benzyl-L-histidine methyl ester, m.p. $114-116^{\circ}C,$ carbobenzoxy-L-valyl-L-tyrosine hydrazide and carbobenzoxy B-benzyl-L-aspartyl-nitro-L-arginine. The first three dipeptides were obtained as crystalline compounds. Imidazole-benzyl-L-histidine was used in the hope that it would block the histidine imidazole against side reactions in steps subsequent to the formation of the C-terminal tetrapeptide. Also, it was through that the imidazole benzylated peptides would be easier to crystallize. This, however, was not the case. The tetrapeptide, carbobenzoxy-L-isoleucyl-L-im, benzyl-histidyl, L-prolyl-L-alanine-nitrobenzyl ester was not obtained in a crystalline form. Neither could the mono-or dihydrobromide of the tetrapeptide free base be induced to crystallize. Carbobenzoxy-L-valyl-L-tyrosine azide was condensed with the tetrapeptide free base to yield the protected hexapeptide; carbobenzoxy-L-valyl-L-tyrosyl-L-isoleucyl-L-im, benzyl, histidyl-L-Prolyl-L-alanine-nitrobenzyl ester. Upon removal of the carbobenzoxy group with hydrogen bromide in acetic acid an amorphous free base hexapeptide ester was obtained. This compound gave the correct C, H, N analysis and contained the six amino acids in the correct ratio. The octapeptide was obtained by condensing this hexapeptide with carbobenzoxy-B-benzyl-L-aspartyl-nitro, L-arginine using the mixed anhydride method of condensation. This amorphous product was proven to be homogenous by chromatography in two solvent systems and upon hydrolysis yielded the eight amino acids in correct ratio. The five protecting groups were removed from the octapeptide by hydrogenolysis over palladium black catalyst. Biological assay of the free peptide indicated that it possessed less than 0.1 per cent of both pressor and oxytocic activity of the phenylalanine8 angiotensin. This suggests that the phenyl group is a point of attachment between angiotensin and its biological receptor site.

• 반도체디스플레이기술학회지
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• 제19권1호
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• pp.29-35
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• 2020

The cure characteristics of three kinds of naphthalene type epoxy resins(NET-OH, NET-MA, NET-Epoxy) with a 2-methyl imidazole(2MI) catalyst were investigated for preparing sheet epoxy molding compound(SEMC) for wafer level package(WLP) applications, comparing with diglycidyl ether of bisphenol-A(DGEBA) and 1,6-naphthalenediol diglycidyl ether(NE-16) epoxy resin. The cure kinetics of these systems were analyzed by differential scanning calorimetry with an isothermal approach, and the kinetic parameters of all systems were reported in generalized kinetic equations with diffusion effects. The NET-OH epoxy resin represented an n-th order cure mechanism as like NE-16 and DGEBA epoxy resins, however, the NET-MA and NET-Epoxy resins showed an autocatalytic cure mechanism. The NET-OH and NET-Epoxy resins showed higher cure conversion rates than DGEBA and NE-16 epoxy resins, however, the lowest cure conversion rates can be seen in the NET-MA epoxy resin. Although the NETEpoxy and NET-MA epoxy resins represented higher cure reaction conversions comparing with DGEBA and NE-16 resins, the NET-OH showed the lowest cure reaction conversions. It can be figured out by kinetic parameter analysis that the lowest cure conversion rates of the NET-MA epoxy resin are caused by lower collision frequency factor, and the lowest cure reaction conversions of the NET-OH are due to the earlier network structures formation according to lowest critical cure conversion.

• Bulletin of the Korean Chemical Society
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• 제33권8호
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• pp.2603-2608
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• 2012

A novel mononuclear supramolecule of copper(II) has been synthesized with Ippyt ligand (Ippyt=3-(4'-imidazole phenyl)-5-(pyrid-2''-yl)-1,2,4-triazole) (1). Compound 1, namely [$Cu(Ippyt)_2(H_2O)_2$], has been characterized by single-crystal X-ray diffraction, IR spectrum, elemental analysis and thermogravimetric analysis. Structure determination reveals that the elongated-octahedral geometry is formed in the vicinity of the copper (II) atom being coordinated by four nitrogen atoms from two Ippyt ligands occupying the equatorial position and two oxygen atoms from two coordinated water molecules in the axial position, which together form the $N_4O_2$ donor set. Hydrogen bonding interactions between nitrogen and oxygen atoms result in the set up of a supramolecular network architecture. Biological properties including antibacterial activity and superoxide dismutase (SOD) mimetic activity of compound 1 have been investigated by agar diffusion method and the modified Marklund method, respectively. The results indicate that compound 1 exhibits a stronger antibacterial efficiency than the parent ligand and it also has a certain radical-scavenging activity.

• 대한화학회지
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• 제39권5호
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• pp.408-413
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• 1995

A few t-amine substituted anilines and amides were synthesized and cyclized to pyrrolo[1,2-a]benzimidazole by heating in various solvents having different polarity. Subsequent nitration of cyclized compound followed by reduction and oxidation of resulting amine afforded quinone such as 7 in 14% yield. The formation of imidazole moiety by thermal cyclization was independent on the solvent polarity. The regiochemistry for the nitration of 4 was unambiguously determined by chemical transformation.

• 한국식품저장유통학회:학술대회논문집
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• 한국식품저장유통학회 2003년도 제23차 추계총회 및 국제학술심포지움
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• pp.134.1-134
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• 2003

The purpose of this study was to investigate the release of p-hydroxybenzoic acid and other compounds from cell wall materials(CWM) and their cellulose fraction from carrot with chemical and enzymatic hydrolysis. To investigate this effect on cell wall chemistry of carrot, alcohol insoluble residue(AIR) of CWM were prepared and were extracted sequentially with water, imidazole, CDTA(-1, -2), Na$_2$CO$_3$(-1, -2), KOH(0.5, 1.0 and 4M), to leave a residue. These were analysed for their carbohydrate and phenolic acids composition. Arabinose and galactose were the main noncellulosic sugars. Phenolics esterified to cell walls in carrot were found to consist primarily of p-hydroxybenzoic acid with minor contribution from vanillin, ferulic acid and p-hydroxybenzaldehyde. p-Hydroxybenzoic acid was quite strongly bound to the cell wall. The contents of p-hydroxybenzoic acid in 0.5M KOH, Na$_2$CO$_3$-2, IM KOH, and ${\alpha}$-cellulose were 2,097, 1,360, 1,140, and 717 $\mu\textrm{g}$/g AIR from CWM, respectively. Alkali labile unknown aromatic compound(C$\sub$7/H$\sub$10/O$_2$) was found in ${\alpha}$ -cellulose hydrolyzate digested with driselase and cellulase. This compound was also found in hydrolyzate of 2 M trifluoroacetic acid at 120$^{\circ}C$ for 2 hours. Driselase treatment solubilized only 46.6 $\mu\textrm{g}$/g of the p-hydroxybenzoic acid from carrot AIR. These results indicate that p-hydroxybenzoic acid was associated with neutral polysaccharides, long chain galactose and branched arabinan from graded alcohol precipitation.