• 대한화학회지
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• 제55권5호
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• pp.787-793
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• 2011

An efficient three-component one-step synthesis of 2,4,5-trisubstituted imidazoles by condensation reaction of 1,2-diketones or ${\alpha}$-hydroxyketones with aromatic aldehydes and ammonium acetate using Zinc (II) [tetra (4-methylphenyl)] porphyrin as a novel and reusable catalyst under ultrasound irradiation at ambient temperature is described. In this method, ${\alpha}$-hydroxyketones as well as 1,2-diketones were converted to their corresponding 2,4,5-trisubstituted imidazoles in excellent yields.

• Bulletin of the Korean Chemical Society
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• 제30권9호
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• pp.2152-2154
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• 2009

• 대한화학회지
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• 제38권1호
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• pp.21-25
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• 1994

이미다졸 고리를 포함하는 lexitropsin에서, DNA minor grooved의 염기쌍(G-C sequence)과 결합하는 부분인 치환이미다졸의 양성자 친화도를 확장분자궤도함수법으로 조사하였다. 그 결과 메틸이미다졸의 경우 염기중심 질소의 $\alpha$위치에 치환된 이미다졸이 N에 치환된 이미다졸보다 양성자 친화도가 약간 더 크게 나타났으며 다른 치환이미다졸의 경우에는 N에 치환된 이미다졸이 ${\alpha}$위치에 치환된 이미다졸보다 양성자 친화도가 더 크게 나타났다. 예상한 바와 같이 이미다졸의 N에 전자를 미는기가 치환될 때 모두 양성자 친화도가 증가함을 알 수 있었다.

• Bulletin of the Korean Chemical Society
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• 제34권5호
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• pp.1508-1512
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• 2013

A simple and efficient synthesis of 2,4,5-trisubstituted imidazoles was achieved via a one-pot three-component cyclocondensation of benzil, aromatic aldehydes, and ammonium acetate in the presence of a catalytic amount of tetrabutylammonium hexatungstate $[TBA]_2[W_6O_{19}]$ as a heterogeneous catalyst under thermal solvent-free conditions. The key features of this methodology are operational simplicity, high yields, short reaction times, and a recyclable catalyst with a very easy work up.

• 대한화학회지
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• 제34권2호
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• pp.184-188
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• 1990

치환 phenacyl bromide와 imidazole과의 반응 및 phenacyl bromide와 치환imidazole과의 반응속도를 전기전도도법으로 측정하였다. 반응속도는 phenacyl bromide의 전자 끄는기에 의하여 촉진되었으며 이 반응은 linear free energy relationship과 isokinetic relationship에 잘 맞았다. 반응속도와 imidazole의 pKa사이에는 Bronsted rule이 잘 적용되었으나 2-methylimidazole의 경우에는 위치장애현상으로 인해 여기서 벗어났다. Acetonitrile 용매하에서는 methanol 용매하에서보다 Kirkwood식에서 예상되는 것보다 훨씬 빠르게 반응속도가 관찰되었다.

• Bulletin of the Korean Chemical Society
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• 제32권7호
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• pp.2385-2390
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• 2011

Preparation of ammonium dihydrogenphosphate supported on alumina ($NH_4H_2PO_4/Al_2O_3$) and its primary application as a solid acid supported heterogeneous catalyst to the synthesis of 1,2,4,5-tetrasubstituted imidazoles by a one-pot, four-component condensation of benzil, aromatic aldehydes, primary amines, and ammonium acetate under thermal solvent-free conditions were described. The results showed that the novel catalyst has high activity and the desired products were obtained in high yields. Furthermore, the products could be separated simply from the catalyst, and the catalyst could be recycled and reused with only slight reduction in its catalytic activity. Characterization of the catalyst was performed by FT-IR spectroscopy, the $N_2$ adsorption/desorption analysis (BET), thermal analysis (TG/DTG), and X-ray diffraction (XRD) techniques.

• Bulletin of the Korean Chemical Society
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• 제30권9호
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• pp.1963-1966
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• 2009

L-Proline has been found to be an efficient organocatalyst for one-pot synthesis of 2,4,5-triaryl substituted imidazole by the reaction of an aldehyde, a benzil and an ammonium acetate. The short reaction time and excellent yields making this protocol practical and economically attractive.

• Bulletin of the Korean Chemical Society
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• 제22권6호
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• pp.633-634
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• 2001

• Bulletin of the Korean Chemical Society
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• 제26권12호
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• pp.2051-2053
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• 2005

• Nuclear Medicine and Molecular Imaging
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• 제41권2호
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• pp.91-96
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• 2007

The measurement of pathologically low levels of tissue $pO_2$ is an important diagnostic goal for determining the prognosis of many clinically important diseases including cardiovascular insufficiency, stroke and cancer. The target tissues nowaday have mostly been tumors or the myocardium, with less attention centered on the brain. Radiolabelled nitroimidazole or derivatives may be useful in identifying the hypoxic cells in cerebrovascular disease or traumatic brain injury, and hypoxic-ischemic encephalopathy. In acute stroke, the target of therapy is the severely hypoxic but salvageable tissue. $^{18}F-MISO$ PET and $^{99}mTc-EC-metronidazole$ SPECT in patients with acute ischemic stroke identified hypoxic tissues and ischemic penumbra, and predicted its outcome. A study using $^{123}I-IAZA$ in patient with closed head injury detected the hypoxic tissues after head injury. Up till now these radiopharmaceuticals have drawbacks due to its relatively low concentration with hypoxic tissues associated with/without low blood-brain barrier permeability and the necessity to wait a long time to achieve acceptable target to background ratios for imaging in acute ischemic stroke. It is needed to develop new hypoxic marker exhibiting more rapid localization in the hypoxic region in the brain. And then, the hypoxic brain imaging with imidazoles or non-imidazoles may be very useful in detecting the hypoxic tissues, determining therapeutic strategies and developing therapeutic drugs in several neurological disease, especially, in acute ischemic stroke.