• Archives of Pharmacal Research
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• 제25권6호
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• pp.786-789
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• 2002

The total synthesis of a norneolignan isolated from Ratanhia, 5-(3-hydroxypropyl)-2-(2'-methoxy-4'-hydroxyphenyl)benzofuran (8), is described. The key steps contain the one-pot reaction for a 2-arylbenzofuran 6 from methyl 3-(4-hydroxyphenyl)propionate with 2-chloro-2-methylthio-(2'-methoxy-4'-acetoxy)acetophenone (5) in the presence of $ZnCl_2$, and reductive desulfurization of the resulting product 6.

• Journal of Pharmaceutical Investigation
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• 제39권3호
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• pp.173-176
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• 2009

A new crystal form of valsartan dipotassium was isolated by recrystallization using the one-pot method. The new crystal form was identified as a monohydrate form ($C_{24}H_{27}N_5O_3K_2.H_2O$) and characterized by diffential scanning calorimetry (DSC), thermogravimetric analysis (TGA) and X-ray powder diffractometry (PXRD). The new crystal data demonstrated to be clearly different from those known for the tetrahydrate form ($C_{24}H_{27}N_5O_3K_2.4H_2O$). It was observed that the monohydrate of vasartan dipotassium salt was completely dissolved in water within 1 hour and its dissolution rate was much faster than anhydrous free form of valsartan.

• Bulletin of the Korean Chemical Society
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• 제33권2호
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• pp.453-458
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• 2012

Reactions of (N-isocyanimino)triphenylphosphorane with (1R)-(-)-campherchinon in the presence of aromatic carboxylic acids proceed smoothly at room temperature and in neutral conditions to afford sterically congested 1,3,4-oxadiazole derivatives in high yields. The reaction proceeds smoothly and cleanly under mild conditions and no side reactions were observed.

• Bulletin of the Korean Chemical Society
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• 제32권5호
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• pp.1703-1708
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• 2011

ZSM-5-$SO_3H$ efficiently catalyzed the one-pot three-component Mannich reaction of aldehydes, anilines, and ketones. ${\beta}$-Aminocarbonyl compounds were obtained in reasonable yields and excellent stereoselectivities when the reaction was carried out at room temperature under solvent-free conditions. Simple experimental conditions and product isolation procedure makes this protocol potential for the development of clean and environment-friendly strategy for the synthesis of ${\beta}$-amino-ketones. The catalyst was recovered and reused for subsequent runs.

• Bulletin of the Korean Chemical Society
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• 제32권5호
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• pp.1635-1639
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• 2011

An efficient and novel positive charge-doping on the sidewalls of multi-walled carbon nanotubes has been achieved in the presence of tetrahydrofuran as a dopant and Lewis acidic ionic liquids, [bmim]$Sb_nF_{5n+1}$ (n ${\geq}$ 2; bmim = 1-butyl-3-methylimidazolium), as an activator, leaving air-stable derivatives having positively charged sidewalls and the counter anions, [MWCNT$^{y+}$][SbF$_6^-$]$_y$ (MWCNT = multi-walled carbon nanotube). The derivatization took place very fast in one-pot and under mild reaction conditions. The ionic structure enabled a tunable dissolution of the derivatives in various solvents through anion exchange.

• 대한화학회지
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• 제55권3호
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• pp.486-489
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• 2011

Potassium dihydrogen phosphate는 마이크로파 조사조건에서 용매 없이 페놀과 아세토아세트산 에틸의 Pechmann 축합반응에 의하여 쿠마린을 합성하는 효과적인 촉매로 밝혀졌다. 이 방법은 쿠마린 합성에 있어서 소량의 촉매를 필요로 하며 수율이 높고, 반응이 깨끗할 뿐만 아니라 반응 시간이 짧은 장점들을 가지고 있다.

• Bulletin of the Korean Chemical Society
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• 제31권2호
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• pp.351-354
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• 2010

Nickel nanoparticles (Ni NPs) appeared to exhibit the catalytic activity in one-pot cyclocondensation reaction for the preparation of 3,4-dihydropyrimidine-2(1H)-ones via Biginelli reaction from aromatic/heteroaromatic/aliphatic aldehydes, urea/thiourea and ethyl acetoacetate under microwave irradiation has been described. The UV absorbance spectra showed metallic Ni characteristics and appreciate with the particle size determined by Transmission electron microscopy (TEM). After reaction course the Ni NPs can be re-covered and reused without any apparent loss of activity.

• Bulletin of the Korean Chemical Society
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• 제31권7호
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• pp.1863-1868
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• 2010

A simple and efficient synthesis of various $\alpha$-aminophosphonates (3a-l) by the reaction of substituted aromatic/heterocyclic aldehydes, 2-amino-6-methoxy-benzothiazole and dibutyl/diphenyl phosphites under microwave irradiation without catalyst was accomplished. The phosphonates were characterized by elemental analysis, IR, $^1H$, $^{13}C$- and $^{31}PNMR$ spectra. They showed promising antimicrobial, anti-oxidant activities depending on the nature of bioactive groups at the $\alpha$-carbon.

• 대한화학회지
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• 제58권4호
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• pp.366-376
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• 2014

Synthesis, structural characterization, and biological activity studies of novel pyrido[2,3-d]pyrimidines (10a-h, 11a-h) are described. Cyclization of cynoacetamides (4, 5) with malonitrile (7) and aldehyde (6a-h) via Hantzsch pyridine synthesis afforded cyanopyridones (8a-h, 9a-h), which on cyclization with formic acid under microwave conditions led to the final product. All the reactions are significantly faster and the isolated yields are remarkably higher in microwave conditions compared to the conventionally heated reactions. The compounds were tested in vitro for their antibacterial activity against Escherichia coli, Pseudomonas aeruginosa, Bacillus subtillus, Staphylococcus aureus, and Micrococcus luteus and antifungal activity against Trichphyton longifusus, Candida albicans, Microsporum canis, Fusarium solani. Compounds 10b, 10e, 11b and 11e exhibited good antibacterial and antifungal activities compared with standards.

• Bulletin of the Korean Chemical Society
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• 제29권8호
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• pp.1545-1553
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• 2008

Using a one-pot reaction technique, monodisperse $\gamma-Fe_2O_3$ nanoparticles were prepared by thermal decomposition of Fe$(CO)_5$ in the presence of a long alkyl chain terminated dendron surfactant. The size of the particles is controlled by adjusting the concentration of the dendron ligands in the reaction solution. Spherical, 2 nm sized nanoparticles were obtained with a 3:1 ratio of dendrons to Fe$(CO)_5$, while 4.6 nm sized particles were formed with a 1:3 ratio. Superparamagetic properties of 2 nm, 4 nm, and 4.6 nm sized particles were measured using a SQUID magnetometer.