• Bulletin of the Korean Chemical Society
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• v.19 no.1
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• pp.86-93
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• 1998

Trans-4-(9-anthrylethenyl)-4'-methyl-2,2'-bipyridine(t-aemb) and its bipyridyl Ru complex $[Ru(bpy)_2(t-aemb)](PF_6)_2$ (bpy=2,2'-bipyridine) 1 have been prepared and their excited state properties have been studied. t-Aemb exhibits solvent-dependent fluorescence and efficient trans→cis photoisomerization. 1 shows very weak fluorescence and its photochemically reactive. Fluorescence is wavelength-dependent. While the excitation into the MLCT band makes the complex fluorescent, direct absorption by the t-aemb ligand leads to the photoreaction of t-aemb ligand and no fluorescence is observed. 1 is considered to behave in part as bichromophoric molecule in which $[Ru(bpy)_3](PF_6)_2$ and anthryl group are covalently linked by ethenyl linkage. Because anthryl moiety is not effectively conjugated with bipyridylethenyl moiety due to steric hindrance, weak fluorescence can be explained due to the efficient energy or electron transfer.

• YAKHAK HOEJI
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• v.33 no.5
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• pp.290-295
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• 1989

2,6-Dimethyl-4-(3'-nitrophenyl)-1,4-dihydropyridine-3-carboxylic acid methyl ester (1) was formylated to 2,6-dimethy-4-(3'-nitrophenyl)-5-formyl-1,4-dihydropyridine-3-carboxylic acid methyl ester (2) in 76% yield. At the elevated temperature, 2,6-dimethyl-4-(3'-nitrophenyl)-1,4-dihydropyridine-3,5-dicarboxylic acid 3-monomethyl ester (3) was also converted into compound 2 in 46% yield. The compound 2 was reduced to 2,6-dimethyl-4-(3'-nitrophenyl)-5-hydroxymethyl-1,4-dihydropyridine-3-carboxylic acid methyl ester (4) in 91% yield. Compound 2 was reacted with triethyl phosphonoacetate to give 2,6-dimethyl-4-(3'-nitrophenyl)-5-(2-ethoxycarbonyl ethenyl)-1,4-dihydropyridine-3-carboxylic acid methyl ester (5) in 50% yield. Reaction between compound 2 and amines (methyl amine, ethylamine, methoxylamine, hydroxyl amine, phenyl hydrazine and 1-amino-4-methyl piperazine) gave six schiff bases 7a, 7b, 7c, 7e, 7f in 81%, 91%, 82%, 81%, 50% and 84% yield, respectively.

• Journal of the Korean Applied Science and Technology
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• v.5 no.2
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• pp.9-15
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• 1988

In order to investigate the amino acid and fatty acid content in Thuja biotae water extract treated with alkaline, it was performed. There are 16 kinds of different amino acid and 20 kinds of different fatty acid in Thuja biotae water extract. An aspartic acid was contained 52％ and proline was contained 10％, particulary, r-aminobutyric acid was analysed. Essential fatty acids; linoleic acid, linolenic acid and arachidonic acid were cotained a lot amount. There are 11 different unknown materials which were identified by GC-MS spectrum, such as N-[($4{\alpha},5{\alpha}$)-cholestan-4-yl]-acetamide; 22,26-Epithio-furost-5-en-3-ol; 2-Methyl-6-(4-methyl-3-cyclohexen-1-yl)-4-heptanone; 3,12,14-Tris(acetyloxy)-pregnane-15,20-dione;22-Methyl-26-thio-furost-5-en-3-ol; 7-Ethenyl-1,2,3,4,4a,4b,5,6,7,9,10,10a-dodecahydro-1,4a,7-trimethyl-1-phenanthrene carboxyaldehyde; Methoxyiminopro-panedioic acid; 13-Methyl-13-${\beta}$-Methyl-13-vinyl-dodecaarp-7-en-3-3-ol; 22-Methyl-26-thio-furost-6-methyl-3-ol; $5{\alpha}-Androstane-2$,11-dione; 9-Methyl-heptadecanoic acid.

• Proceedings of the Plant Resources Society of Korea Conference
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• 2023.04a
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• pp.18-18
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• 2023

Two new phenanthrenes, namely, (1R,2R)-1,7-hydroxy-2,8-methoxy-2,3-dihydrophenanthrene-4(1H)-one (1) and 2,7-dihydroxyphenanthrene-1,4-dione (2), were isolated from the ethyl acetate-soluble fraction of Dendrobii Herba, together with the eleven known compounds, densiflorol B (3), 6,7-dimethoxyphenanthrene2,5-diol (4), dehydroorchinol (5), 1,5,7-trimethoxy-2-phenanthrenol (6), denthyrsinin (7), ephemerantol A (8), lusianthridin (9), moscatilin (10), gigantol (11), 3-[(1E)-2-(3-hydroxyphenyl)ethenyl]-5-methoxyphenol (12) and (-)-syringaresinol (13). Structures of 1 and 2 were elucidated by analyzing 1D and 2D NMR as well as HR-ESI-MS data. The absolute configuration of compound 1 was confirmed by ECD spectroscopic method. In cytotoxicity evaluation using FaDu human hypopharyngeal squamous carcinoma cell line, compounds 3-6, 8, 10 and 12 showed activities, with IC₅₀ values ranging from 2.55 to 17.70 μM. Among them, compound 10 exhibited remarkable cytotoxic activity with IC₅₀ value of 2.55 μM. This is the first report on the anticancer mechanistic study of compound 10 in HNSCC including FaDu cells.

• Applied Chemistry for Engineering
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• v.7 no.2
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• pp.379-386
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• 1996

Photosensitive compound, 1-methyl-4-[2-(4-diethylacetylphenyl)ethenyl] pridinium methosulfate(SbQ-A salt), was synthesized from dimethyl sulfate, terephthalaldehyde mono-(diethylacetal) and 4-picoline. SbQ-A salts were reacted with poly(vinyl alcohol)s, (PVA) in aqueous solution with phosphoric acid as catalyst to give photosensitive PVA-SbQ with different SbQ content and molecular weight. Relative photosensitivity of PVA-SbQ was determined by gray scale(GS) method. The rotative sensitivity of PVA-SbQ increased with increasing amount of bound SbQ in the case of high molecular weight(MW=77,000-79,000g/mol) as substrate and decreased with decreasing molecular weight of PVA with about constant(1.3mol%) amount of bound SbQ. The most sensitive polymer was obtained when SbQ group content in PVA-SbQ reached about 2.63mol% in the case of high molecular weight(77,000-79,000g/mol) PVA. This sample showed 90 times greater sensitivity than dichromated PVA as reference photosensitive system. PVA-SbQ photosensitive polymer synthesized was applied to the photolithographic screening process of phosphor on the panel of cathode ray tube(CRT). Phosphor slurry was made with PVA-SbQ, phosphor, a small amount of surfactant and other additives using water as medium. The slurry was coated onto panel, dried by heater, exposed to UV light and then developed by distilled water. When a small amount of cationic surfactant such as cetyltrimethylammonium chloride was used in the slurry formulation, the sharpness of phosphor pattern was equal to or better than that of dichromated PVA photosensitive polymer system used currently.

• Korean Journal of Organic Agriculture
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• v.28 no.1
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• pp.95-108
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• 2020

To develop an environment-friendly fungicide for controlling tomato wilt diseases, antifungal active substance was isolated Rheum australe D. Don roots against Fusarium oxysporum f. sp. lycopersici, a pathogen of tomato wilt, in this study. Methanol extract obtained from Rheum australe roots was successively fractionated with hexane, chloroform, ethyl acetate, butanol and water. The ethyl acetate fraction, which showed the highest antifungal activity, was separated by column chromatography, and 60 subfractions were obtained. The 60 subfractions were anlayzed for antifungal activities by bioassay. The active compound was identified as 5-[(E)-2- (3-hydroxy-4-methoxyphenyl)ethenyl]benzene-1,3-diol (rhapontigenin) by NMR and GC-MS analysis. As a result of testing antifungal activity of rhapontigenin against Fusarium oxysporum, EC₅₀ of rhapontigenin was showed strong antifungal activity at 7.48 mg/L. Therefore, this study showed that the Rheum australe roots extract can be a potential candidate which is a environment-friendly fungicide against Fusarium oxysporum.

• Journal of the Korean Society of Tobacco Science
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• v.20 no.2
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• pp.198-204
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• 1998

This study was conducted to evaluate the effect of far IR radiation for the elimination of sidestream smoke components in a closed room. The measurements covered particle sizes of 13.8-542.5 nm, particle concentration, TSP, UVPM, FPM, solanesol, and the following gases and vapor components of smoke: carbon dioxide, carbon monoxide, nicotine, and 3-ethenyl-pyridine. Also, the changes of smoke odor strength by far IR radiation were tested by using the electronic nose system. There was no difference between control and far IR radiation in changes of the concentration of $CO_2$ and CO. The concentrations of TSP, UVPM, FPM, solanesol, nicotine, and 3-ethenylpyridine were reduced by far IR radiation. The growth and diminishing rate of RSP diameter was accelerated by far IR radiation compared with control. There was a little difference of smoke odor change with far IR radiation by electronic nose system analysis. Our results indicated that the use of far IR radiation had a little effect on changes of solid, vapor, and odor of smoke, but it had no effect on gaseous components.

• Bulletin of the Korean Chemical Society
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• v.23 no.2
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• pp.330-336
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• 2002

A quantum-chemical investigation on the conformations and electronic properties of bis[2-{2-methoxy-4,6-di(t-butyl)phenyl}ethenyl]benzenes (MBPBs) as building block for ${\pi}$-conjugate polymer are performed in order to display the effects of t-butyl and methoxy group substitution and of kink(ortho and meta) linkage. The conjugation length of the polymers can be controlled by substituents and kink linkages of backbone. Structures for the molecules, o-, m-, and p-MBPBs as well as unsubstituted o-, m-, and p-DSBs were fully optimized by using semiempirical AM1, PM3 methods, and ab initio HF method with 3-21G(d) basis set. The potential energy curves with respect to the change of single torsion angle are obtained by using semiempirical methods and ab initio HF/3-21G(d) basis set. The curves are similar shape in the molecules with respect to the position of vinylene groups. It is shown that the conformations of the molecules are compromised between the steric repulsion interaction and the degree of the conjugation. Electronic properties of the molecules were obtained by applying the optimized structures and geometries to the ZINDO/S method. ZINDO/S analysis performed on the geometries obtained by AM1 method and HF/3-21G(d) level is reported. The absorption wavelength on the geometries obtained by AM1 method is much longer than that by HF/3-21G(d) level. The absorption wavelength of MBPBs are red shifted with comparison to that of corresponding DSBs in the same torsion angle because of electron donating substituents. The absorption wavelength of isomers with kink(orth and meta) linkage is shorter than that of para linkage.

• Korean Journal of Materials Research
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• v.19 no.9
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• pp.510-515
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• 2009

The compound of 2,6-Bis[(9-phenylcarbazolyl)ethenyl]naphthalene (BPCEN-1), 2-[6-{1-Cyano-2-(9-phenylcarbazoly)vinyl}naphthyl]-3-(9-phenylcarbazolyl)acrylonitrile (BPCEN-2), 2,6-Bis[{4-(1-naphthy l)phenylamino} styrenyl] naphthalene (BNPASN-1), 2-[6-{1-Cyano-2-(naphthylphenylaminophenyl) vinyl}naphthyl]-3-(naphthylphenylaminophenyl)acrylonitrile (BNPASN-2) was analyzed electrochemically and spectroscopically and can be obtained by bonding phenylcarbazolyl, naphthylphenylaminophenyl and -CN ligands to 2,7-naphthalene. The electrochemical and spectroscopic study resulted in the P-type (BPCEN-1, BNPASN-1) being changed to N-type (BPCEN-2, BNPASN-2) according to -CN bonding despite having the same structure. The value of band gap(Eg) was revealed to be small as HOMO had shifted higher and LUMO lower. The Eg value for naphthylphenylaminophenyl ligand was reduced because it has a smaller HOMO/LUMO value than that of phenylcarbazolyl from a structural perspective. The electrochemical HOMO/LUMO values for BPCEN-1, BPCEN-2, BNPASN-1, BNPASN-2 were measured to be 5.55eV / 2.83eV, 5.73eV / 3.06eV, 5.48eV / 2.78eV, and 5.53eV / 2.98eV, respectively. By -CN ligand, the UV max, Eg and PL max were shifted to longer wavelength in their spectra and the luminescence band could be also confirmed to be broad in the photoluminescence (PL) spectrum.

• Journal of Photoscience
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• v.4 no.3
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• pp.147-160
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• 1997

INTRODUCTION : Various types of organic reactions in the crystalline state, so-called "topochemical reaction", have been reported in this century." Among the reactions, [2+2] photocycloaddition of diolefin crystals are one of the most intensively investigated examples. In the topochemical reaction in a pure sense, the space group symmetry is perfectly preserved throughout the reaction as were demonstrated by the crystalline-state photopolymerization of 2,5-distyrylpyrazine (2,5-DSP) and photodimerization of propyl $\alpha$-cyano-4-[2-(4-pyridyl) ethenyl]cinnamate. 2,5-DSP was initially prepared by Franke and in 1958 Koelsch and Gumprecht described briefly in their article of diazine-derivatives that it was found that the compound (2,5-DsP) was converted into a colorless insoluble polymer (\ulcorner) dec. 331~331$\circ$ when the solid was exposed for a few hours to ultraviolet light. Wright described in his book as if Koelsch and Gumprecht had investigated both the structure of the photoproduct and the crystal structure 2,5-DSP in detail. However, in the paper, they have not described any study on chemically correct analysis and crystallography of the resulting photoproduct at all. In 1967, one of present authors (M. H.) independently made the same observation as Franke that brilliant yellow crystal of 2,5-DSP was converted into powdery white substance under the sunlight in the course of a preparative study of pyrazine-2,5-dicarboxylic acid from 2,5-DSP. He investigated this phenomenon and concluded for the first time that a linear highmolecular-weight polymer crystal ([$\eta$] > 3.0 in $CF_3COOH$ solution) with recurring cyclobutane units in the main chain, had been produced from 2,5-DSP crystal by the action of sunlight.on of sunlight.