• Bulletin of the Korean Chemical Society
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• v.22 no.12
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• pp.1380-1384
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• 2001

The chemoselective reactions of 1,n-dicarbonyl compounds with allyl halides using indium metal were investigated. $\alpha-Ketoesters$ such as ethyl pyruvate, ethyl 3-methyl-2-oxobutyrate and ethyl benzoylformate reacted with a variety of allyl halides i n the presence of indium to afford hydroxy unsaturated carbonyl compounds in good to excellent yields in MeOH/HCl at $25^{\circ}C.$ For the allyl bromide, the presence of various substituents at the $\alpha$ or $\gamma$ position exhibited little effects on both the reaction rates and yields. Ethyl acetoacetate or ethyl levulinate was treated with allylindium reagent to give hydroxy unsaturated carbonyl compounds in good yield. These results mean that both reactivity and selectivity are independent of the distance between carbonyl groups. 2,3-Butanedione or 1-phenyl-1,2-propanedione reacted with allylindium to produce monoallylation product as major compound.

• Journal of the Korean Chemical Society
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• v.57 no.1
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• pp.94-98
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• 2013

A new family of thiazole heterocycles, namely [4-(1H-benzoimidazol-2-yl)-thiazol-2-yl]-benzylidene-amines has been synthesized by the condensation of 4-(1H-Benzoimidazol-2-yl)-thiazol-2-ylamine with various aromatic aldehydes and N-[4-(1H-benzoimidazol-2-yl)-thiazol-2-yl]-N'-benzylidene-hydrazines through the cyclization of 1-(1H-benzoimidazol-2-yl)-2-bromo-ethanone with arylthiosemicarbazones. The target compounds are achieved by using 1-(1H-Benzoimidazol-2-yl)-ethanone as starting material. The chemical structures of all newly synthesized compounds were confirmed by their IR, $^1H$ NMR and Mass spectral data. Further the compounds were used to evaluate their antimicrobial activity and found that the appreciable antimicrobial activity by some of the title compounds.

• KSBB Journal
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• v.29 no.2
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• pp.118-123
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• 2014

It was confirmed that malodor connected with an air-conditioner in an automobile is caused by microbial volatile organic compounds (MVOCs) produced by microorganisms getting into an air-conditioner when it is operating. Chemicals such as hydrogen sulfide, dimethyl sulfide, nbutyric acid, n-valeric acid, iso-valeric acid, n-octanol and toluene were detected above the odor threshold inside the automobile. The characteristics of a funky odor in the air blown into the automobile were due to detected sulfur compounds (hydrogen sulfide and dimethyl sulfide). Dimethyl sulfide was produced by microorganisms such as Aspergillus versicolor, Methylobacterium aquaticum, Herbaspirillum sp. and Acidovorax sp. In addition, the characteristics of a sour odor in the air blown into the automobile were due to detected organic acids (n-butyric acid, n-valeric acid and iso-valeric acid). N-valeric acid and iso-valeric acid were generated from Aspergillus versicolor, while iso-valeric acid was produced by Methylobacterium aquaticum. In addition, the odor intensity of the air blown into the automobile was affected by the concentration of detected sulfur compounds and organic acids. On the other hand, it is estimated that chemicals such as hydrogen sulfide, n-octanol and n-butyric acid detected in the air blown into the automobile were produced by non-identified species of microorganisms.

• Bulletin of the Korean Chemical Society
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• v.11 no.3
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• pp.209-214
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• 1990

A series of compounds consisting of 4'-oxybenzylidene-4-n-butylaniline, a mesogen, and a p-substituted phenoxyterephthaloyl structure a non-mesogen, interconnected through a central hexamethylene spacer were synthesized and their thermal behavior and liquid crystallinity were studied. p-Substituents included in this study are H, Cl, CN, $NO_2,\;n-C_4H_9O$ and phenyl groups. The compounds having phenyl and $n-C_4H_9O$ substituents are enantiotropic and form smectic-A(SA) and nematic (N) phases. The compound with $NO_2$ substituent is monotropic and forms only a nematic phase on heating the solid, whereas it forms nematic as well as $S_A$ phases on cooling the isotropic liquid. The rest compounds were found to be non-liquid crystalline. This is in great contrast to the fact that the monomesogenic model compound 4'-n-hexyloxybenzylidine-4-n-butylaniline forms $S_B,\;S_C,\;S_A$ and N phases enantiotropically.

• Archives of Pharmacal Research
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• v.19 no.2
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• pp.95-99
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• 1996

Four N-adamantyl n-alkanamides were prepared by amide condensation reaction between amantadine and n-alkanoic acid. Their enhancing activity on the penetration of ibuprofen through rabbit skin from petrolatum ointment was evaluated in in-vivo experiment. The experiments showed that the compounds have a strong transdermal penetration-enhancing activity, and their activities were comparable with that of Azone. The measurements of the fluorescence polarization of DP[-i-labelled DPPC liposomes showed that these compounds considerablly decreased the phase transition temperature of the liposomes. The mechanism of the transdermal penetration-enhancing activity of the compounds was ascribed to the reduction of the resistance to drug flux of the stratum corneum lipid layers due to the loose packing of the layers when the bulk head group of the enhancers inserts into the layers.

• Journal of the Korean Applied Science and Technology
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• v.3 no.1
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• pp.65-71
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• 1986

Four amphoteric surfactants, 1-(N-alkyl-N,N-dimethyl ammonio)-4-naphthalene sulfonates, were prepared by the alkylation of 1-(N,N-dimethylamino)-4,naphthalene sulfonic acid with chloroalkanes such as 1-decylchloride, 1-tetradecyl chloride and 1-hexadecyl chloride. These quaternary ammonium compounds such as 1-(N-decyl-N, N-dimethylammonio)-4-naphthalene sulfonate, 1-(N-dodecyl-N,N-dimethylammonio)-4-naphthalene sulfonate, 1-(N-tetradecyl-N,N-dimethylammonio)-4-naphthalene sulfonate and 1-(N-hexadecyl-N,N-dimethylammonio)-4-naphthalene sulfonate could be separated by means of thin layes chromatography and column chromatography. The surface chemical properties such as surface tension, foaming power, foam stability, wetting efficiency and solubilizing effect for these four compounds were measured. Also critical micelle concentration and hydrophilic-lipophilic balance(HLB) were evaluated. These compounds showed good surface as O/W type emulsifying agent and detergent.

• Applied Chemistry for Engineering
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• v.9 no.1
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• pp.66-70
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• 1998

Several liquid crystalline monomers were synthesized and characterized to utilize as new matrix materials of liquid crystal/polymer composite films for display application. Liquid crystalline compounds which have azo group as center link, cyano group at one of the terminal position in common and bromoalkyl(azo(n)), azidoalkyl(AZI(n)), aminoalkyl(ALC(n)) as the terminal group were synthesized and identified respectively by FT-lR, $^1H-NMR$ spectrometer and elemental analysis. All these compounds exhibited nematic liquid crystalline region in the certain temperature range as determined by DSC and polarized optical microscope. These liquid crystalline compounds also showed a typical even-odd effect in both $T_{KN}$ and $T_{NI}$ due to conformational change as the length of terminal alkyl chain, $-(CH_2)n-$. was varied.

• The Plant Pathology Journal
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• v.26 no.2
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• pp.170-177
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• 2010

Bacillus licheniformis N1, previously developed as a biofungicide formulation N1E to control gray mold disease of plants, was investigated to study the bacterial traits that may be involved in its biological control activity. Two N1E based formulations, bacterial cell based formulation PN1E and culture supernatant based formulation SN1E, were evaluated for disease control activity against gray mold disease of tomato and strawberry plants. Neither PN1E nor SN1E was as effective as the original formulation N1E. Fractionation of antifungal compounds from the bacterial culture supernatant of B. licheniformis N1 indicated that two different cyclic lipopeptides were responsible for the antimicrobial activity of the N1 strain. These two purified compounds were identified as iturin A and surfactin by HPLC and LCMS. The purified lipopeptides were evaluated for plant disease control activity against seven plant diseases. Crude extracts and purified compounds applied at 500 ${\mu}g/ml$ concentration controlled tomato gray mold, tomato late blight and pepper anthracnose effectively with over 70% disease control value. While iturin showed broad spectrum activity against all tested plant diseases, the control activity by surfactin was limited to tomato gray mold, tomato late blight, and pepper anthracnose. Although antifungal compounds from B. licheniformis N1 exhibited disease control activity, our results suggested that bacterial cells present in the N1E formulation also contribute to the disease control activity together with the antifungal compounds.

• Journal of the Korean Society of Food Science and Nutrition
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• v.24 no.2
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• pp.219-227
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• 1995

Natto is a Japanese tradiational food made from whole soybeans by the fermentation of Bacillus natto. This study was attempted to improve the taste of Natto, garlic(2%) and red pepper oleoresin(0.2%) were added. Conventional Natto(N-1), garlic Natto(N-2), red pepper oleoresin Natto(N-3), garlic and red pepper oleoresin Natto(N-4) were prepared. Volatile flavor components, fatty acid, organic acid, pH and titratable acdity in all samples were investigated. The experimental results revealed the presence of 62 volatile components in conventional Natto. Among there, the major flavor compounds were identified to be 2, 5-dimethylpyrazine, trimethyl-pyrazine, 2, 6-bis91, 1-dimethylethyl) phenol. Seventy-one volatile compounds were detected in N-2, and major compounds were identified to be methyl-2-propenyl disulfide, 2, 6-bis(1, 1-dimethylethyl)phenol and 2, 5-dimethylpyrazine. The amounts of volatile compounds, 2-methyoxyphenol and 1, 2-benzenedicarboxylic acid increased by addition of garlic, where as, 1,2 -propanediol, 1-hexanol and 2, 5-dimethylpyrazine decreased. The compounds, 4, 5-dihydroxy-5-propyl-1H-pyrazole, 1, 1, 3-trimethylcyclopentane were identified in N-3. The compounds, such as trimethylpyrazine, 3-ethyl-2,5-dimethylpyrazine increased by addition of red pepper oleoresin, whereas 1,2-propanediol, 1-hexanol and 2,5-dimethylpyrazine decreased. Fatty acid compositions were mainly consisted of linoleic acid(43.66~55.89%) and followed by oleic, palmitic, linolenic, stearic, arachidic, myristic acid. The organic acids we4re identified to be citric(28.2~30.6), acetic(50.0~73.3) and pyroglutamic acid(2.1~3.7).

• YAKHAK HOEJI
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• v.20 no.1
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• pp.19-26
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• 1976

Sixteen compounds of 2-aminobenzothiazole derivatives were synthesized from alkyl ($C_{1-5}$) p-aminosalicylate by thiocyanation reaction. The NMR spectra of synthesized compounds showed that they were actually mixture of 5-hydroxy-6-alk-oxycarbonyl-2-aminobenzothiazole [alkoxy=methoxy(Ia), ethoxy (IIa), n-propoxy (IIIa), iso-propoxy (IVa), n-butoxy (Va), iso-butoxy (VIa), n-amoxy (VIIa), iso-amoxy(VIIIa)] and 7-(1b), ethoxy(IIb), n-propoxy(IIIb), iso-propoxy(IVb), n-butoxy(Vb), iso-butpxy (VIb), n-amoxy (VIIb), iso-amoxy (VIIIb)]. The mixtures of two isomeric benzothiazole were separated by two isomers varied with the kind of alkyl chain in alkyl p-aminosalicylate. These compounds were subjected to the test for antimicrobial activities using Staphylococcus aureus and Escherichia coli by tube dilutioin method. The seven compounds, Ia, IIa, IIIa, VIa, IIIb, IVb and Vb showed inhibition of the growth of S. aureus at the concentration of 10${\mu}$g/ml. As to the growth of E. coli, IVb, VIb, VIIb, and VIIIb were observed inhibition at the concentration of 1${\mu}$g/ml. Ia, IIa, IIIa, VIIa, Va, VIIIa, and IIb exhibited potential antimicrobial activities against showed inhibition of the growth of E.coli at the concentration of 100${\mu}$/ml.