• Journal of Adhesion and Interface
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• v.12 no.2
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• pp.56-61
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• 2011

In the present study, glucose-sensitive hydrogels using phenylboronic acid (PBA) without glucose oxidase and catalase were prepared. The swelling-shrinking behavior of the hydrogel according to the variation of pH and glucose and ionic concentrations was investigated. The swelling ratio of the hydrogel containing PBA increased with increasing the glucose concentration and the volume was very sensitively varied with the pH. However, the ionic concentration did not change significantly the relative swelling ratio on the hydrogel, indicating that the hydrogel was dimensionally stable.

• Applied Biological Chemistry
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• v.39 no.1
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• pp.84-88
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• 1996

To determine brassinolide in rice(Oriza sativa L.) using HPLC equipped with fluoresence detector, a highly sensitive fluorescence reagent. 1-cyanoisoindole-2-m-phenylboronic acid, was synthesized from the reaction of o-phthaldehyde, m-phenylboronic acid and KCN, then was reacted with brassinolide. The formation ratio of brassinolide boronate exhibited 90% up at the ratio of $20\;:\;1({\mu}g/{\mu}g)$ of 1-cyanoisoindole-2-m-phenylboronic acid and brassinolide respectively. The detection limit of brassinolide boronate with fluoresence detector was 0.16 ng. Brassinolide was detected in heading stage(biomass : 10 g) and panicle formation stage(biomass : 100 g) of the rice(Oryza sativa L.) with quantity of $0.8\;{\mu}g\;and\;0.2\;{\mu}g$respectively. However, brassinolide was not detected in blooming and elongation stage.

• Bulletin of the Korean Chemical Society
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• v.31 no.5
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• pp.1309-1313
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• 2010

The effects of boronic acid on the fluoride-selective chemosignaling behavior of a merocyanine dye were investigated. In the presence of phenylboronic acid (PBA), N-methylquinolinium-based merocyanine dye displayed fluoride-selective chromogenic signaling behavior over other commonly coexisting anions in the micromolar concentration range. Signaling is produced by a fluoride-induced displacement of the dye from its complex with PBA, resulting in a significant chromogenic signal for the fluoride ion. This signaling was successfully analyzed using a ratiometric analysis of the UV-vis absorption in response to changes in fluoride ion concentration. A PBA substituted with an electron withdrawing group was found to exhibit a more pronounced signal. Polymer-bound PBA also exhibited useful fluoride-selective signaling behavior.

• YAKHAK HOEJI
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• v.57 no.5
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• pp.357-361
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• 2013

A formal synthesis of Lespedezol $A_1$ has been accomplished. The key feature of this synthesis involves an efficient and powerful palladium-catalyzed cross coupling reaction of diazocarbonyl compound with bis(benzyloxy)phenylboronic acid for the key 3-aryl-chromen-4-one intermediate, which was difficult to be prepared by Suzuki coupling reaction in the previous study. The versatile and efficient synthetic procedure would facilitate synthesis of pterocarpenes and their derivatives.

• Bulletin of the Korean Chemical Society
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• v.28 no.10
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• pp.1863-1866
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• 2007

• Membrane Journal
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• v.23 no.1
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• pp.80-91
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• 2013

Metal-templated condensation of cyclohexanedione dioxime and phenylboronic acid in the presence of Fe(II) sulfate heptahydrate proceeds cleanly in methanol to furnish the Fe(II) clathrochelate. An organic/inorganic hybrid membranes composed of Fe(II) clathrochelate and polyethersulfone was prepared by using phase inversion method. For membrane preparation, the Fe(II) clathrochelate was highly soluble (3~5 g/L) in DMF, NMP, and DMAc, which meets the requirements for the solubility of metal complexes in polar aprotic solvent used in membrane preparation. It was stable even in the presence of strong acids, such as trifluorosactic acid (pKa = 0.3). It was characterized by UV-vis spectroscopy, and their stability in solution phase studied in the presence of (i) strong acids or (ii) competing chelates. Organic/inorganic hybrid membranes were prepared with polyethersulfone, polyvinylpyrrolidone, p-toluenesulfonic acid, Fe(II) clathrochelate and DMF by using nonsolvent induced phase inversion method. The addition of Fe(II) clathrochelate leads increase of surface pore density, mean pore size and flux. We can obtain highly asymmetric membranes by addition of Fe(II) clathrochelate.

• Applied Biological Chemistry
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• v.41 no.4
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• pp.251-256
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• 1998

The analytical method of ${\beta}-ecdysone$, the insect moulting hormone, by high performance liquid chromatograph (HPLC) with UV detector was developed using boronic ester derivatization and applied to the extracts of Ajuga iva, Silene otites and Schistocerca egg. Derivatization of yield with methyl-, butyl-, and phenyl-boronate was completed under mild conditions with 20-hydroxyecdysone. The conversion ratios of boronate were estimated to be 70% in methylboronic acid, 89% in butylboronic acid and 93% in phenylboronic acid. Phenylboronate showed a high sensitivity and demonstrated an effective separation on HPLC. The optimum temperature and reaction time for derivative formation were $25^{\circ}C$ and 20 min. respectively. ${\beta}-Ecdysone$ was effectively identified in extracts of Ajuga iva, Silene otites and Schistocerca egg by the HPLC method.

• Bulletin of the Korean Chemical Society
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• v.19 no.10
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• pp.1059-1063
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• 1998

Regiospecific total syntheses of (±)-11-deoxy-4-methoxy-10-oxo-βrhodomycinone (21a) and (±)-11-deoxy-1-methoxy-10-oxo-β-rbodomycinone (21b) are described. 2-(2-Bromoethyl)-1,3-dioxane (6) was transformed to naphthalenone 12, which was condensed with (phenylsulfonyl)-isobenzofuranone 13 to afford 7,8-dihydro-9-ethyl-6-hydroxy-4-methoxynaphthacen-5,12-dione (15). Epoxide 16 prepared from olefinic compound 15, reacted with HF/Pyr (7:3) to give 17. Dihydroxylation of 17 with t-BuOK/P(OMe)3/O2, selective cis-diol protection of mixed compounds 18 with phenylboronic acid in toluene, separation of cis-boronate 19 and trans-diol 20 by column chromatography on silica gel, and cleavage of the boronate group of 19 with 2-methylpentane-2,4-diol in acetic acid completed the construction of 21.

• Bulletin of the Korean Chemical Society
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• v.32 no.5
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• pp.1475-1482
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• 2011

New spiro[benzo[c]fluorene-7,9'-fluorene] (SBFF)-based blue host materials, 9-phenyl-SBFF (BH-4P) and 5,9-diphenyl-SBFF (BH-6DP), were successfully prepared by spiro-formation of 9-phenyl-7H-benzo[c]fluoren-7-one with 2-bromobiphenyl via lithiation and reaction of 5,9-dibromo-SBFF with phenylboronic acid through the Suzuki reaction, respectively. Diphenyl-[4-(2-[1,1;4,1]terphenyl-4-yl-vinyl)-phenyl]-amine (BD-1) and N,N-diphenyl-N',N'-diphenyl-SBFF-5,9-diamine (BD-6DPA) were used as dopant materials. Blue OLEDs with the configuration ITO/N,N'-bis-[4-(di-m-tolylamino)phenyl]-N,N'-diphenylbiphenyl-4,4'-diamine (DNTPD)/bis[N-(1-naphthyl)-N-phenyl]benzidine (NPB)/host:5% dopant/SFC-137/Al-LiF were prepared from the two host materials doped with BD-1 and BD-6DPA dopants and the devices composed of BH-4P and BH-6DP doped with BD-6DPA showed blue EL spectra at 458 and 463 nm at 7 V and luminance efficiencies of 4.58 and 4.88 cd/A, respectively.

• Bulletin of the Korean Chemical Society
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• v.32 no.8
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• pp.2584-2592
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• 2011

Nickel nanoparticle-poly(N-vinyl-2-pyrrolidone)/$TiO_2-ZrO_2$ composite (Ni-PVP/$TiO_2-ZrO_2$) was prepared by in situ polymerization method. The physical and chemical properties of Ni-PVP/$TiO_2-ZrO_2$ were investigated by XRD, FT-IR, BET, TGA, SEM and TEM techniques. The catalytic performance of this novel heterogeneous catalyst was determined for the Suzuki-Miyaura cross-coupling reaction between aryl halides and phenylboronic acid in the presence of methanol-water mixture as solvent. The effects of reaction temperature, the amount of catalyst, amount of support, solvent, and amount of metal for the synthesis of Ni-PVP/$TiO_2-ZrO_2$, were investigated as well as recyclability of the heterogeneous composite. The catalyst used for this synthetically useful transformation showed considerable level of reusability besides very good activity.