• Archives of Pharmacal Research
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• 제25권3호
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• pp.240-249
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• 2002

Dibenzyl-g-butyrolactone and 1,2,3,4-tetrahydro-2-naphthoic acid $\gamma$-lactone (TNL) derivatives were synthesized and evaluated for cytotoxic activity against some cancer cell lines. It was found that TNL derivatives with a shorter distance between C-4 in ring A and C'-2 in ring C were more cytotoxic, while dibenzyl-${\gamma}$-butyrolactones with a longer one were nearly inactive. In TNL series, presence of 3,4-dioxy group in ring A and 2-methoxy group in ring C was essential for the enhancement of the activity.

• 한국생물공학회:학술대회논문집
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• 한국생물공학회 2002년도 생물공학의 동향 (X)
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• pp.411-414
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• 2002

Acylated homoserine lactones (AHLs) are membrane-permeant signal molecules responsible for biofilm formation of gram-negative bacteria via a unique mechanism known as quorum sensing. A target specific bioassay employing the AHL-responsive Agrobacterium tumefaciens reporter strain has been developed to identify new AHL-like compounds from natural products, which could be developed into antifouling compounds. By varying the X-gal concentration, incubation time, solvent for sample preparation and the sample loading procedure, it was possible to detect low level AHLs up to $10^1nM$. The length of the acyl chain of the AHLs was found to affect the sensitivity of this bioassay.

• 생약학회지
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• 제31권3호
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• pp.306-309
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• 2000

Two sesquiterpene lactones were isolated from methanol extracts of the whole plants of Youngia japonica (L.) DC. by the silica gel column chromatography and recrystallization. On the basis of spectrometric studies including $^1H-NMR,\;^{13}C-NMR,\;DEPT,\;^1H-^1H\;COSY,\;^{13}C-^1H\;COSY$, IR and MS, compounds 1 and 2 were identified as derivatives of 10(14)-guaien-12, 6-olide, isoamberboin and isolipidiol, respectively. This is the first report on the isolation of isoamberboin and isolipidiol from Youngia japonica (L.) DC.

• Natural Product Sciences
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• 제16권3호
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• pp.143-147
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• 2010

The chromatographic separation of a methanol extract of Artemisia princes led to the isolation of two sesquiterpene lactones, artecanin (1) and canin (2), together with a flavonoid, eupatilin (3). Their structures were determined by 1D, 2D-NMR and MS data analysis. All of the isolates were evaluated for their potential to inhibit the LPS-induced production of nitric oxide in murine macrophage RAW 264.7 cells. Compounds 1 - 3 inhibited nitric oxide production with $IC_{50}$ values of 19.5, 20.4 and 25.1 ${\mu}M$, respectively.

• 한국식품위생안전성학회:학술대회논문집
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• 한국식품위생안전성학회 1994년도 하계 학술 심포지움
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• pp.17-22
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• 1994

Food additives are minor components which are used to enhance nutritive or sensory values, and to improve shelf life of foods. In foods, natural additives are preferred over artificial or synthetic materials because of concern on food safety. Many biotechnological techniques have been applied to the production of food additives since the biotechnology has been utilized to prodyce many flavor components such as glutamate, 5'-nucleotides, esters, 2,3-bytadione, pyrazines, terpenes, and lactones. Natural flavors, fragrances, sweetners, and colorants can be produced by plant cell culture. Many lactic acid bacteria produce bacteriocins such as nisin or diplococcin. These bacteriocins are used as safe preservatives in foods and many researches on the improvenment of bacteriocin productivity by genetic engineering are in progress.

• 생약학회지
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• 제29권2호
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• pp.67-70
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• 1998

Two sesquiterpene lactones were isolated from the flowers of Chrysanthemum boreale Makino by the silica gel column chromatography and recrystallization. On the basis of spectrometric studies including $^1H-NMR,\;^{13}C-NMR,\;DEPT,\;^1H-^1H\;COSY,\;{13}C-^1H\;COSY$, IR and Mass, compounds 1 and 2 were identified as germacranolide, tulipinolide and costunolide, respectively. And they showed antibacterial activity against Vibrio parahaemolyticus, Bacillus subtilis, Bacillus cereus and Staphylococcus aureus. This is the first report that Chrysanthemum boreale contained tulipinolide and costunolide.

• 통합자연과학논문집
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• 제3권2호
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• pp.61-71
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• 2010

Hydrosilanes possessing reactive Si-H bond are used in synthesizing various types of polysilanes by dehydrocoupling under the influence of various organometallic promoters. Catalytic Si-Si/Si-O coupling of hydrosilanes with hydrosilanes, alcohols, and lactones to silicon-based polymers are described in this article as selective examples of our recent research developments. These silicon-containing polymers can be used as a precursor to prepare useful functional materials for fabricating electronic devices.

• 한국식품영양과학회지
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• 제27권4호
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• pp.563-567
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• 1998

Volatile flavor components of edible portion of leek(Allium tuberosum R.) were extracted by SDE(simultaneous steam distillation and extraction) method using the mixture of n-pentane and diethylether (1 : 1, v/v) as an extract solvent and analyzed by GC-FID and GC/MS. Identification of the volatile flavor components was mostly based on the RI of GC and mass spectrum of GC/MS. A total of sixty-five components from leek extract were classified as 28 sulfur-containing compounds, 12 aldehydes, 9 alcohols, 4 lactones and esters, 3 acids and hydrocarbons, and 2 miscellaneous compouds. The sulfur-containing compounds were predominant in leek extract. Dimethyl disulfide(19.47%) and dimethyl trisulfide(17.38%) were the main compounds and trans-1-propenyl methyl disulfide, trans-2-hexenal and methyl allyl disulfide were also detected large amounts in leek.

• Archives of Pharmacal Research
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• 제23권4호
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• pp.329-331
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• 2000

4-(p-Chlorophenyl)tetralone (6) and 7-chloro-5-(p-chlorophenyl)tetralone (9) are key intermediates for the development of benzazepinone derivative haftens. These compounds could be synthesized from 4-phenyltetralone derivatives by triflic acid catalyzed Friedel-Crafts reaction. The reaction mechanism of Friedel-Crafts alkylation/acylation with lactones in triflic acid is presented. According to our tentative research, ring opening of protonated lactone (2) occurs in alkyl cleavage and the rate of the reaction is not dependent on concentration of triflic acid. So, alkylation of lactone in Friedel-Crafts reaction is presumed to be $A_{AL}$ 1. In second step, intramolecular acylation of the intermediates 4 to 6, 4 can be transformed to a triflic acid-carboxylic anhydride and then the cyclization is undergone after leaving of the triflate anion.

• Bulletin of the Korean Chemical Society
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• 제30권5호
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• pp.1012-1020
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• 2009

We developed an efficient three-step synthetic protocol of $\gamma$-hydroxybutenolides starting from the Baylis-Hillman adducts: (i) bromination, (ii) Barbier reaction and (iii) one-pot $K_2CO_3$-mediated synthesis of $\gamma$-hydroxybutenolides. In addition, we showed the synthetic applicability of butenolides including self-dimerization, conjugate addition reaction, and alkylations.