• Bulletin of the Korean Chemical Society
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• 제29권8호
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• pp.1519-1524
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• 2008

We have investigated the photophysics of the acetone radical cation in the vacuum ultraviolet energy region by multiphoton ionization combined with time-of-flight mass spectrometry in a cluster beam. We have found that the loss of methyl radical from the acetone radical cations is remarkably suppressed at 10.5 eV when they are solvated by a few neutral acetone molecules. The cluster ion mass spectra obtained by nanosecond and picosecond laser pulses reveal that there are intermolecular processes, occurring in several tens of picoseconds, which are responsible for the survival of the acetone cations in clusters. This remarkable solvation effect on the yield of the methyl radical loss from the acetone cation can be rationalized by the intracluster vibrational energy redistribution and the self-catalyzed enolization which compete with the methyl radical loss process.

• Bulletin of the Korean Chemical Society
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• 제6권5호
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• pp.284-287
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• 1985

Cyanoisopropyl radical derived from azobisisobutyronitrile (AIBN) by either thermolysis or photolysis reacts with oxygen to give cyanoisopropylperoxy radical which then was converted to acetone and cyano radical and/or acetyl cyanide and methyl radical. Of these products, acetone formed was quantitatively determined by the addition of thianthrene cation radical perchlorate to the reaction mixture. The results showed that 55.7 mmol, 16.9 mmol, and 16.0 mmol of acetone were formed for 7 hours from 1 mol of AIBN at $82{\pm}1^{\circ}C$ in acetonitrile, carbon tetrachloride, and benzene, respectively. However, 22.2 mmol of acetone was formed from photolysis of 1 mmol of AIBN in acetonitrile. The value decreased to 13.2 mmol by bubbling argon into the solvent prior to photolysis.

• Bulletin of the Korean Chemical Society
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• 제7권2호
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• pp.150-153
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• 1986

Co-sensitized photooxygenation of 1,1-diphenyl-2-vinylcyclopropane (VCP-DPh) with 9,10-dicyanoanthracene and biphenyl in oxygen-saturated acetonitrile solution produced 3,3-diphenyl-5-vinyl-1,2-dioxolane as the major product. The same photoproduct was obtained by acetone sensitized photooxygenation in oxygen-saturated acetone solution. However, VCP-DPh remained intact when directly irradiated with DCA or irradiated with Rose Bengal to generate singlet oxygen. A mechanism involving a cosensitizer radical cation and sensitizer radical anion is proposed.

• 한국식품영양과학회지
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• 제45권3호
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• pp.327-332
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• 2016

본 연구는 목이버섯을 대상으로 acetone, ethanol 및 ethyl acetate 등의 용매를 이용하여 확보된 각각의 추출물에 대한 폴리페놀 함량, 플라보노이드 함량, DPPH 라디칼 소거능 및 ABTS 라디칼 소거능 등의 항산화 활성과 6종의 균주에 대한 디스크 확산법으로 항균 활성 등을 측정하였다. 목이버섯의 폴리페놀 함량과 플라보노이드 함량은 용매에 따라 유의적 차이는 없었으나 극성이 큰 acetone과 ethanol에서 ethyl acetate 추출물에 비해 다소 높게 조사되었으며, 플라보노이드 함량은 ethyl acetate> acetone> ethanol 추출물 순으로 측정되었다. DPPH 라디칼 소거능과 ABTS 양이온 라디칼 소거능은 각각 58.7~23.1%, 32.2~10.0% 등으로 나타났으며, 특히 목이버섯 ethanol 추출물에서 높은 항산화 활성을 확인하였다. 그리고 목이버섯의 항균 활성 측정 결과 acetone 추출물이 Bacillus subtilis, Staphylococcus aureus, Micrococcus luteus, Escherichia coli, Pseudomonas aeruginosa 및 Enterobacter cloacae 등 6개의 균주 모두에 대하여 활성을 확인할 수 있었으며, 특히 acetone, ethanol 및 ethyl acetate 추출물 모두에서 다른 균에 비해 B. subtilis에 대하여 생육저해환이 다소 크다는 것을 알 수 있었다. 이렇듯 본 연구를 통하여 목이버섯 추출물의 항산화 및 항균 활성을 확인함으로써 향후 목이버섯을 이용한 천연 첨가제 혹은 건강 기능성 식품의 원료소재 등으로 이용 가능할 것으로 생각한다.

• Bulletin of the Korean Chemical Society
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• 제6권6호
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• pp.358-361
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• 1985

Thianthrene cation radical perchlorate (1) reacted with azo-bis-2-phenoxy-2-propane (6) to give thianthrene (2), cisthianthrene-5,10-dioxide, 5-(p-hydroxyphenyl) thianthrenium perchlorate (10), acetone, phenol, and 5-(2-propenyl) thianthrenium perchlorate (11) when the mole trtio of 1 to 6 was 1:1. Among the products, 11 was a new compound. However, when the corresponding mole ratio was 5:1, 11 was not formed. Similar result was obtained for azo-bis-2-(p-nitrophenoxy)-2-propane.

• 한국광학회:학술대회논문집
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• 한국광학회 2008년도 동계학술발표회 논문집
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• pp.319-320
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• 2008

• 한국자원식물학회지
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• 제27권1호
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• pp.29-34
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• 2014

배롱나무 가지가 기능성화장품 소재 및 천연물 의약품으로써 활용 가능성이 있는지 검토해 보고자 그 생리활성을 확인하기 위해서 DPPH radical 소거능 측정, ABTS radical cation decolorization 활성, Nitrite 소거작용, collagenase 저해활성을 측정하였다. DPPH radical 소거능의 경우 배롱나무 가지의 아세톤 추출물은 50 ppm에서 73%의 항산화능을 나타내었으며 합성항산화제인 BHA는 50 ppm에서 90% 이상의 높은 항산화능을 보여준다. ABTS radical cation decolorization 활성은 50 ppm에서 78% 이상 높은 항산화활성을 보였으며 BHA의 경우 50 ppm에서 96% 이상 활성을 보여준다. Nitrite 소거작용 측정은 대조군인 합성항산화제 BHA와 비교하여 모든 농도에서 우수한 아질산염 소거능을 보여주었다. 배롱나무 가지 추출물은 50 ppm의 저농도에서 63% 이상의 활성을 보여주었으며 1000 ppm에서 73%의 활성을 보이는 것과 비교하여 저농도에서도 높은 활성을 보여주는 것을 알 수 있다. Collagenase 저해활성 측정 결과 대조군인 천연물 (-)-epigallo-catechin-3-gallate와 비교하여 모든 농도에서 우수한 collagenase 저해활성을 보여주었으며 50ppm의 저농도에서도 85% 이상의 높은 collagenase 저해활성을 보여주었다. 이와 같은 결과로 미루어 보아 대조군인 인공 합성 항산화제인 BHA와 비교하여 배롱나무 가지 추출물은 항산화 효과, 아질산염 소거작용 그리고 주름개선에 우수한 효과가 나타나는 것을 수 있다. 따라서 화장품 산업 및 천연물 의약품의 원료로 이용하기 위한 적합한 천연 물질인 것으로 판단된다.

• Bulletin of the Korean Chemical Society
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• 제1권2호
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• pp.49-54
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• 1980

Solutions of $Ni^{2+}$ and $Cd^{2+}$ were mixed with the solutions of various dibasic organic acids in the presence of cation exchange resin at room temperature. The distribution ratios of the metal ions between resin and solution were measured, using radioactive metal ions as tracer. From the observed variation of the distribution ratios with acid anion concentrations, it was concluded that $Ni^{2+}$ and $Cd^{2+}$ formed one-to-one complexes with succinate, malonate, o-phthalate and tartarate ions in aqueous, 20 % ethanol-water and 20 % acetone-water solutions. The results of the present study indicated that the relative stabilities of the complexes in solution increased generally in the order : $Ni^{2+}$ < $Cd^{2+}$ complexes. Succinate < malonate < o-phthalate < tartarate complexes. Aqueous < mixed solvent systems.

• Journal of Photoscience
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• 제7권4호
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• pp.143-148
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• 2000

Studies have been conducted to explore single electron transfer(SET) promoted photocyclization of ($\omega$-phthalimidoalkoxy)acetic acids(alkoxy=ethoxy, n-propoxy and n-butyloxy). Photocyclizations occur in methanol or acetone in high yields to produce cyclized products in which phthalimide carbonyl carbon is bonded to the carbon of side chain in place of the carboxylic group. These photocyclizations are thought to proceed through pathways involving intramolecular SET from oxygen in the $\alpha$-carboxymethoxy groups to the singlet excited state phthalimide moieties followed by decarboxylation of the intermediate $\alpha$-carboxymethoxy cation fadicals and cyclizations by radical coupling. The photocyclizations occur ca. three times faster in both methanol or acetone with one equivalent of sodium hydroxide added to the reactions and occur slower in acetone than in methanol. The efficient and regiselective cyclization reactions observed for photolyses in methanol represent synthetically useful processes for construction of heterocyclic compounds.

• 한국전기전자재료학회논문지
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• 제29권1호
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• pp.35-39
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• 2016

In this research, we focused on the improvement of cy3 dye's characteristics for LCD color filter. Solubility and thermal stability are main characteristics of dyes for LCD color filter. We performed experiment to change counter cation of cy3 dyes with alkoxy substituent for these purposes. These cy3 dyes (1b~5b) were prepared through the synthetic procedure of three steps. The synthesized new cy3 dyes were charaterized by using NMR, FT-IR, UV/Vis spectroscopy, and TGA. These cy3 dyes showed purple color and maximum absorption wavelength (${\lambda}_{max}$) in the range of 578~590 nm in UV/Vis spectrum. We confirmed that solubility and thermal stability of cy3 dyes were dependent on the structure of counter cation. Cy3 dyes with alkoxy substituent have good solubility in organic solvents such as dichloromethane, methanol, and acetone. Especially, Cy3 dye with 4-nitrobenzyl counter cation (5b) gave excellent solubility characteristics.