• YAKHAK HOEJI
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• v.18 no.4
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• pp.249-254
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• 1974

Eighteen 2-aryl-3-(5-nitro-2-furyl) acrylamides were synthesized as antimicrobial agent, by the condensation of 2-(p-sulbstituted phenyl)-3-(5-nitro-2-furyl) acryloyl chloride with amino component, such as sulfisozxazole, sulfamethoxypyridazine and sulfadimethoxine. All compounds showed fair bacteriostatic activity against staphylococcus aureus 6538p, Bacillus subtilis, Escherichia coli, and Klebsiella pneumoniae. 2-(p-Hydroxyphenyl)-and 2-(p-acetoxyphenyl) compounds also showed antimicrobial activity against Saccharomyces cerevisiae 396 and Aspergillus oryzae.

• Bulletin of the Korean Chemical Society
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• v.22 no.2
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• pp.139-140
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• 2001

• Bulletin of the Korean Chemical Society
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• v.24 no.7
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• pp.916-920
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• 2003

Photoreactions of N-(2,4-dibromonaphthyl)arenecarboxamides in basic medium result in the intramolecular substituted products, 2-aryl-8-bromonaphthoxazoles in moderate yields and further photoreactions of the products afford the reduced products, 2-arylnaphthoxazoles. These reactions are straightforward for syntheses of naphthoxazole derivatives. Since the intramolecular photosubstitution of the bromoarenecarboxamide by the oxygen of its amide group is more effective than the photoreduction of the substituted product, 2-aryl-8- bromonaphthoxazole in basic medium, the intramolecular substituted product, 2-aryl-8-bromonaphthoxazole can be isolated. A charge-transfered excited singlet state of an imidol form of the 2-bromoarenecarboxamide is involved in the photosubstitution, whereas an excited triplet state of the 2-aryl-8-bromonaphthoxzole is closely involved in the photoreduction.

• Bulletin of the Korean Chemical Society
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• v.34 no.3
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• pp.936-942
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• 2013

Series of (E)-1-aryl-3-(2-pyrrolyl)-2-propenones, that were aldol condensation products between pyrrole-2-carbaldehyde and m- and p-substituted acetophenones, were prepared and their $^1H$ and $^{13}C$ NMR spectra were examined to obtain the information on the conformation of the enone system. Similar studies were carried out with (E)-3-aryl-1-(2-pyrrolyl)-2-propenones that were prepared from 2-acetylpyrrole and m- and p-substituted benzaldehydes. The substituent chemical shifts were studied by applying the Hammett relationship.

• Bulletin of the Korean Chemical Society
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• v.12 no.2
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• pp.193-196
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• 1991

The $^{13}C-NMR$ shifts of a series of para-substituted $8-aryl-tricyclo[3.2.1.0^{2,7}]oct-8-yl$ and $9-aryl-tricyclo[3.3.1.0^{2,8}]-non-9-yl$ cations were measured in $FSO_3H/SO_2ClF\ at\-90^{\circ}$ in order to examine whether the ${\rho}^{C^+}$ values can be used as a measure of the geometric influence on the charge delocalization resulting from ${\rho}$ conjugation in rigid tricyclopropylcarbinyl cations. Plot of the ${\Delta}{\delta}^{C+} shifts against the ${\sigma}^{C+}$ constants revealed excellent linear correlation. The 8-aryl tricyclooctyl systems yielded a ${\rho}^{C+}$ value of -5.00 with r = 0.9962. Previous investigation of the 9-aryl-tricyclononyl systems gave a correlation coefficient of r = 0.9948 with a slope of ${\rho}^{C+}$ = -4.95. A fair parallelism exists between the results of $^{19}F-NMR $ studies and the change of ${\rho}^{C+}$ value in these cations. Consequently, it is established that the ${\rho}^{C+}$ value can be used to explain the mechanism of charge stabilization of the rigid cyclopropylcarbinyl cation such as tricyclo $[3.2.1.0^{2,7}]oct-8-yl$ cation.

• Journal of the Korean Chemical Society
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• v.51 no.6
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• pp.520-525
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• 2007

Three-component coupling of thiourea/urea, various structurally diverse aromatic aldehydes and ammonium acetate is catalyzed by activated fly ash in dry media under microwave irradiation to give 6-aryl-1,2,4,5-tetrazinan- 3-thiones/ones in good yields. The structure of 6-aryl-1,2,4,5-tetrazinan-3-thiones/ones have been elucidated on the basis of their melting points, elemental analysis, MS, IR, 1H NMR, D2O exchange, 13C NMR and two dimensional NMR spectral studies including Homonuclear Correlation (HOMOCOR) and Heteronuclear Single Quantum Correlation (HSQC) spectra.

• Bulletin of the Korean Chemical Society
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• v.33 no.4
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• pp.1154-1158
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• 2012

A room-temperature ionic liquid (RTIL) derived from 1,4-diazabicyclo[2.2.2]octane (DABCO) consisting of tetrafluoroborate anion, 1-butyl-4-(4-sulfonylbutyl)-1,4-diazoniabicyclo[2.2.2]octane hydrogen sulfate tetrafluoroborate ($[C_4DABCOC_4SO_3H][BF_4][HSO_4]$) was synthesized and catalytically evaluated in the synthesis of 14-aryl-14H-dibenzo[a,j]xanthenes by cyclocondensation reaction of ${\beta}$-naphthol and aryl aldehydes. This novel RTIL with an acidic $SO_3H$ group showed high catalytic activity with good to excellent yields of the desired products in short reaction times. Moreover, the catalyst could be recovered and reused at least three times with only slight reduction in its catalytic activity.

• Archives of Pharmacal Research
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• v.13 no.1
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• pp.78-81
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• 1990

N-Aryl-N'(4-hydroxy-6-methyl-2-pyrimidinyl)guanidines (IIa-c) were prepared by cyclization of N-arybiguanides (Ia-c) with ethyl acetoacetate. Coupling of compounds (IIa-c) with the appropriate diazotized arylamine gave N-aryl-N'-(5-arylhydrazono-6-methyl-4-oxopyrimidin-2-yl) guanidines (IIIa-f). Whereas, their chlorination with phosphorus oxychloride followed by treatment of N-aryl-N'-(4-Chloro-6-methyl-2-pyrimidinyl)guanidimes (IVac) with the appropriate arylamine afforded the corresponding 4-arylamino derivatives (Vaf). Compounds (IIa-f) were also formed when compounds (1a-c) were treated with ethyl 2-arylhydrazono-3-oxobutyrates. The antimircobial testing of some of the prepared compounds against some pathogenic microorganisms revealed that only two have a marked effect against Escherichia coli.

• Bulletin of the Korean Chemical Society
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• v.17 no.6
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• pp.506-510
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• 1996

The syntheses and photoreactions of haloarenes, in which the aryl and haloaryl moieties are tethered by a simple alkyl group, were studied. For 2-benzyl-1-halobenzene, in which two aryl moieties were connected by methylene group, photoreduced product, diphenylmethane, was obtained along with the minor formation of the photocyclized product, fluorene, in acetonitrile solvent. For 1-halo-2-phenethylbenzene, in which two aryl moieties were connected by ethylene group, photocyclized products, 9,10-dihydrophenanthrene and phenanthrene, were obtained along with the minor formation of photoreduced product, bibenzyl, in acetonitrile solvent. The photoreaction selectivities in several solvent systems were studied: In cyclohexane, 2-benzyl-1-chlorobenzene was photoreduced more effective than 2-benzyl-1-bromobenzene; In the presence of NaOH, 1-halo-2-phenethylbenzenes gave 9,10-dihydrophenanthrene and, in the presence of toluene, they gave phenanthrene. A radical reaction mechanism is proposed for the explanation of the reactions. This study shows that the photoreaction of haloarene, in which haloaryl and aryl moieties are tethered by ethylene group, can be used for ring formation of 9,10-dihydrophenanthrene otherwise difficultly accessible.

• Korean Chemical Engineering Research
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• v.43 no.6
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• pp.662-667
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• 2005

2,3-Dihydrobenzofuran derivatives, important intermediates of medicines and agricultural chemicals, were prepared from aryl methallyl ethers over MCM-41 mesoporous material catalysts. Two mesoporous materials with Si/Al mole ratios of 40 and 50 were prepared to investigate the effect of acid site concentration on their catalytic activities. Aryl methallyl ethers with various substituents on their benzene rings were used to investigate the effect of electron density on benzene ring on the conversion of the ethers and the yield of 2,3-dihydorbenzofuran derivatives. The catalyst with a high acid site concentration showed high conversions, but it is difficult to correlate the yield of the derivatives with the acid site concentration. The increase in the electron density of the benzene ring by introducing electron-donating groups accelerated Claisen rearrangement reaction, resulting in the enhanced yield of the derivatives. On the other hand, the decrease in the electron density by introducing electron-attracting groups accelerated the cracking reaction of aryl methallyl ether by acid catalysts, producing phenol derivatives rather than 2,3-dihydrobenzofuran derivatives.