• Bulletin of the Korean Chemical Society
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• v.32 no.3
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• pp.885-888
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• 2011

We report the first vibrational band assignment of imidazole trimer (IMT) solvated in helium nanodroplets. Several congested vibrational bands of imidazole (IM) clusters were obtained in the frequency region of $3513-3515\;cm^{-1}$ and vibrationally resolved due to the extremely low temperature (0.37 K) and very weak solutesolvent interaction environments of helium droplets. The unambiguous free NH band assignment was achieved with an aid of pick-up oven temperature dependence and vibrational transition moment angle (VTMA) experiments as well as density functional theory (DFT) calculations. The band at $3514.3\;cm^{-1}$ is attributed to the free NH stretching mode of linear IMT clusters, easily formed by the dipole-dipole interactions of IM in ultracold helium nanodroplets.

• BMB Reports
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• v.46 no.3
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• pp.151-156
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• 2013

Phylogenetic and amino acid sequence analysis indicated that rice allene oxide synthase-1 (OsAOS1) is CYP74, and is clearly distinct from CYP74B, C and D subfamilies. Regio- and stereo-chemical analysis revealed the dual substrate specificity of OsAOS1 for (cis,trans)-configurational isomers of 13(S)- and 9(S)-hydroperoxyoctadecadienoic acid. GC-MS analysis showed that OsAOS1 converts 13(S)- and 9(S)-hydroperoxyoctadecadi(tri)enoic acid into their corresponding allene oxide. UV-Visible spectral analysis of native OsAOS1 revealed a Soret maximum at 393 nm, which shifted to 424 nm with several clean isobestic points upon binding of OsAOS1 to imidazole. The spectral shift induced by imidazole correlated with inhibition of OsAOS1 activity, implying that imidazole may coordinate to ferric heme iron, triggering a heme-iron transition from high spin state to low spin state. The implications and significance of a putative type II ligand-induced spin state transition in OsAOS1 are discussed.

• Bulletin of the Korean Chemical Society
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• v.15 no.8
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• pp.673-679
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• 1994

$^1H$ NMR spectra of imidazole, 2-and 4(5)-methylimidazole, histamine, L-histidine, L-histidine methyl ester, N${\alpha}$-acetyl-L-histidine, and L-carnosine coordinated to the paramagnetic undecatungstocobalto(II)silicate ($SiW_{11}Co$) and undecatungstonickelo(II)silicate ($SiW_{11}Ni$) anions are reported. For these complexes the ligand exchange is slow on the NMR time scale and the pure resonance lines of the free ligand and the complexes have been observed separately at room temperature. Two different complexes are formed, depending upon which nitrogen atom of the imidazole ring is coordinated to the cobalt or nickel ion of $SiW_{11}M$. Thus the NMR spectrum of a $D_2O$ solution containing a ligand and $SiW_{11}M$ consists of three sets of lines originating from the free ligand and two complexes. All NMR lines of the $SiW_{11}Co$ complexes have been assigned unequivocally using the saturation transfer technique. The temperature dependence of some spectra are also reported. The NMR spectra of some complexes show that the internal rotation of the substituent on the imidazole ring is hampered by the heteropolyanion moiety even at room temperature.

• Polymer(Korea)
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• v.39 no.3
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• pp.461-467
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• 2015

This paper reports the combined effects of the triblock copolymer surfactant poly(ethylene glycol)-poly(propylene glycol)-poly(ethylene glycol) (PEG-PPG-PEG) and imidazole on the opto-electrical and mechanical properties of poly(3,4-ethylenedioxythiophene) (PEDOT)-based thin films prepared via vapor phase polymerization (VPP) using ferric p-toluenesulfonate as a catalyst. Various PEDOT-based thin films were synthesized using PEG-PPG-PEG and imidazole alone and in combination to compare and correlate their effects on film properties. The improved conductivity of the PEDOT films was higher than $1300S{\cdot}cm^{-1}$ when the surfactant and imidazole were used together. The PEG-PPG-PEG chain length was also varied to identify the best conditions for the VPP-based preparation of PEDOT thin films.

• Journal of the Korean Chemical Society
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• v.48 no.2
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• pp.137-143
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• 2004

The determination of 2-mercapto-1-methyl-imidazole (MMI) in 5.0${\times}10^{-2}$ M lithium perchlorate suporting electrolyte has been investigated by the differential pulse polarography. The optimum condition of MMI analysis was as follows; -0.9 volts initial potential, 0.08 mV pulse height, 2 mV/sec scan rate, and medium mercury drop size. Standard calibration curve showed a good linearlity in the range of 1.0${\times}10^{-7}M\;to\;8.0{\times}10^{-5}$ M and the detection limit has been (2.2${\pm}0.1){\times}0.1^{-9}$ M. This method was applicated for the determination of MMI in antithyroid drug without interference of additives.

• Analytical Science and Technology
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• v.8 no.1
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• pp.17-23
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• 1995

The determination method of 2-mercapto-1-methyl-imidazole(MMI) in $5.0{\times}10^{-2}M$ lithium perchlorate solution has been investigated by the differential pulse polarography. The optimum conditions for the determination of MMI were as fellows; -0.9 volt(vs. Ag/AgCl) initial potential, 80mV pulse height, 2mV/sec scan rate, and medium mercury drop size. The calibration curve showed a good linearlity in the range of $1.0{\times}10^{-7}M$ to $8.0{\times}10^{-5}M$ and the detection limit was $2.2{\times}10^{-9}M$. This method was applicable to the determination of MMI in thyroid drugs without interference from the additives.

• Biomolecules & Therapeutics
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• v.26 no.5
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• pp.494-502
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• 2018

Breast cancer is currently the most prevalent cancer in women, and its incidence increases every year. Azole antifungal drugs were recently found to have antitumor efficacy in several cancer types. They contain an imidazole (clotrimazole and ketoconazole) or a triazole (fluconazole and itraconazole) ring. Using human breast adenocarcinoma cells (MCF-7 and MDA-MB-231), we evaluated the effects of azole drugs on cell proliferation, apoptosis, cell cycle, migration, and invasion, and investigated the underlying mechanisms. Clotrimazole and ketoconazole inhibited the proliferation of both cell lines while fluconazole and itraconazole did not. In addition, clotrimazole and ketoconazole inhibited the motility of MDA-MB-231 cells and induced $G_1$-phase arrest in MCF-7 and MDA-MB-231 cells, as determined by cell cycle analysis and immunoblot data. Moreover, Transwell invasion and gelatin zymography assays revealed that clotrimazole and ketoconazole suppressed invasiveness through the inhibition of matrix metalloproteinase 9 in MDA-MB-231 cells, although no significant changes in invasiveness were observed in MCF-7 cells. There were no significant changes in any of the observed parameters with fluconazole or itraconazole treatment in either breast cancer cell line. Taken together, imidazole antifungal drugs showed strong antitumor activity in breast cancer cells through induction of apoptosis and $G_1$ arrest in both MCF-7 and MDA-MB-231 cells and suppression of invasiveness via matrix metalloproteinase 9 inhibition in MDA-MB-231 cells. Imidazole drugs have well-established pharmacokinetic profiles and known toxicity, which can make these generic drugs strong candidates for repositioning as antitumor therapies.

• Journal of the Korean Chemical Society
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• v.43 no.3
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• pp.257-263
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• 1999

Ln-macrocyclic([20]DOTA) complexes, [Ln([20]DPTA)(NO_{3})(H_{2}O)](NO_{3})_{2} \cdotxH_{2}O{Ln(III)=Pr, Sm, Gd, Dy}, which had been synthesized from 2, 6-diformyl-p-cresol(DFPC), was placed in methanol for 2 days, and $[Ln([20]DPTA)(NO_{3})(CH_{3}OH)]^{2+}$ was formed. The equilibrium constants(L) for the substitution of coordinated $CH_{3}OH$ in the Ln-[20]DOTA complexes by various auxiliary ligands, $L_{a}(=monodentate ligands; pyridine, imidazole, triethylamine, diethylamine, piperidine) were determined spectroscopically at $25^{\circ}C$ and 0.1M. The pKa of auxiliary ligand is in the order of pyridine < imidazole < triethylamine < diethylamine < piperidine, however the K has shown the trend of pyridine < imidzole < diethylamine < piperidine < triethylamine.

• Journal of the Korean Institute of Electrical and Electronic Material Engineers
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• v.16 no.12
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• pp.1121-1124
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• 2003

We report the photo (PL) and electro luminescence (EL) properties of new conjugated compounds based on imidazole moiety, 4,4' -di(4,5 diphenyl-N-imidazolyl)stilbene(DDPIS) and 4,4'-di(2,4,5-triphenyl-N-imidazolyl)stilbene(DTPIS), as emitting materials. ITO/m-MTDATA/NPB/DDPIS/Alq3/LiF/AI device shows blue EL spectrum at 456 ㎚ and 0.3 cd/ A and turn on voltage at 7 ∼ 8 V. DTPIS shows blue EL spectrum at around λmax=453㎚ and 0.5 cd/A efficiency in ITO/m-MTDATA/NPB/DTPIS/Alq3/LiF/Al device.

• Bulletin of the Korean Chemical Society
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• v.23 no.5
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• pp.647-654
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• 2002

The synthesis and characterization of third- and fifth-generation poly(propylene imine) dendrimers terminated with imidazole moieties is reported. Functionalization was achieved using simple peptide coupling reagents. These materials were characte rized by MALDI-MS, NMR, and titration. The use of these endgroup-functionalized dendrimers as catalysts for the hydrolysis of 2,4-dinitrophenyl acetate is described. Molecular simulations provide a basis for interpreting the catalytic data.