• YAKHAK HOEJI
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• v.35 no.1
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• pp.7-10
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• 1991

For the purpose of developing of anticariogenic agents, P-phenylphenol derivatives were synthesized and determined their antibacterial activities against a cariogenic bacterium, Streptococcus mutans. Among synthetic compounds, 2-nitro-6-bromo-p-phenylphenol showed as potent antibacterial activity as magnolol and honokiol.

• Journal of Photoscience
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• v.1 no.2
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• pp.131-133
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• 1994

Optical spectra of 5-amino-2H-1, 2, 4-thiadiazoline-3-one (AT) and some 2-aroyl-5-aroylamino derivatives are reported. Absorption spectra of 2-aroyl-5-aroylamino derivatives show bathochromic shift due to AT group and other substituents of phenyi ring. Weak emission is observed for some derivatives.

• Proceedings of the Korean Vacuum Society Conference
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• 2011.02a
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• pp.10-10
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• 2011

Graphene and graphene derivatives have attracted enormous attention from various research fields for applications in electronic devices, transparent electrodes, biosensors, drug delivery system and surface coatings. In the viewpoint of chemist, the chemical structure of graphene derivatives seems intriguing but detailed structures are being revealed only recently while engineering approaches for various applications are being executed very actively. Recently, several reports are available on interactions of graphene with biomolecules including proteins and nucleic acids. In this talk, I'll introduce recent studies which harness graphene derivatives for developing bioanalytical platforms to quantitatively analyze various enzyme activities. The systems rely on attractive interaction between graphene oxide and nucleic acids or phospholipids.

• Archives of Pharmacal Research
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• v.13 no.4
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• pp.342-346
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• 1990

Several new pyridine, pyridinethione, pyrazole [3, 4-b]-pyridine, pyrido [1, 2-a]-1, 3-thiazine and pyrido[1, 2-a] pyridine thione derivatives have be synthesised via the reactions of 2-methyl-3-ethoxycarbonyl-4-phenyl-5-cyano-1, 4, 5, 6-tetrahydro-pyridine-6-one 2 with different rfeagents. The structures of the newly synthesised derivatives were established on the basis of elemental analyses and spectral data studies.

• Archives of Pharmacal Research
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• v.17 no.2
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• pp.119-123
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• 1994

The synthesis of 3a, 3b, 7a fro Benzpthiazepinone and 1,4-dihyropyridine derivatives is described. Benzothiazepinone nad 1,4-dihydropyridine derivatives were prepared according to literature procedure. The key reactions involve esterification and amidation of benzothize-pinone nad 1,4-dihydropyridine derivatives.

• YAKHAK HOEJI
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• v.45 no.4
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• pp.352-356
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• 2001

A simple and rapid determination of total retinol from various pharmaceuticals containing retinol derivatives was described. Retinol derivatives were hydrolyzed with alcoholic KOH to alcoholic retinol, which was determined by HPLC. Pretreatments and HPLC conditions depend on the kind of retinols and preparation forms. The total amount of alcoholic retinol could be determined with this method from many pharmaceutical preparation of retinol derivatives. Treating time of KOH, acidic reagents and HPLC conditions were investigated.

• Bulletin of the Korean Chemical Society
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• v.23 no.12
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• pp.1806-1810
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• 2002

We have described the synthesis and biological activity of novel retinamide . The retinamide derivatives were synthesized by introducing functional side chains into the 4-hydroxy group of 4-HPR. The activities could be dependent on the side chain length, functional group, and hetero atom. The antiprolife-rative potential of the derivatives was assessed by MTT assay in HCT116 cancer cell lines.

• YAKHAK HOEJI
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• v.43 no.1
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• pp.28-32
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• 1999

Four derivatives of kojic acid were synthesized and their inhibitory activities against tyrosinase were evaluated. The C-2 hydroxymethyl and C-7 hydroxyl of kojic acid were replaced by carboxylate and amine, respectively. These derivatives were coupled to L-phenylalanine, producing two amide compounds. The carboxylate derivative (3), its amide compound (5), and the amine derivative (7) were weak inhibitors. The amide compound (9) where amine derivative (7) coupled to L-phenylalanine showed strong inhibitory activity ($IC_{50}=24.6{\;}{\mu}M$) comparable to kojic acid.

• Proceedings of the Membrane Society of Korea Conference
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• 2004.05a
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• pp.170-174
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• 2004

Most of thin film composite reverse osmosis membranes include amide linkages, which are susceptible to chlorine attack resulting in N-chloro derivatives. This study examined a new method based on post-treatment of reverse osmosis membrane with various silane derivatives to improve chlorine resistance. The silane derivatives contain one alkyl group and three alkoxy groups such as trifluoromethyltrimethoxysilane, 3-aminopropylmethoxydiethoxysilane and 3, 3, 3-trifluoropropyltrimethoxysilane. Compared to commercial membranes, silane derivatives coated membranes showed significantly enhanced chlorine durability.

• Journal of the Korea Institute of Military Science and Technology
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• v.5 no.2
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• pp.62-71
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• 2002

A free oscillation technique for obtaining the dynamic stability derivatives in yaw is applied to the pure yawing motion. The procedure of wind tunnel testing is to compute the derivatives after measuring deflecting angles of the model during the free oscillating motion. The charging compressed air is supplied for the initial excitation. The results of this experiment predicted feasible characteristics of the yawing motion, comparing with the data previously reported in the literature.