• YAKHAK HOEJI
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• v.44 no.3
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• pp.272-278
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• 2000

The antiinflammatory mechanism of NSAIDs is attributed to the reduction of prostaglandin synthesis by the direct inhibition of cyclooxygenase. Inhibition of prostaglandin production in organs such as stomach and kidney can result in gastric lesions, nephrotoxicity and increased bleeding. In this study, newly designed COX-2 inhibitors, synthesized 1,2-benzothiazine derivatives, were screened in vitro for selectivity of COX-1 and COX-2 inhibition properties. Lead compounds in the structure-activity relationship were studied to synthesize new highly selective COX-2 inhibitors.13 determine inhibitory effect of COX-2, synthesized 1,2-benzothiazine derivatives were screened with accumulation of prostaglandin by lipopolysaccharide (LPS) in aspirin-treated macrophages and murine macropharge cell. Some of synthesized 1,2-benzothiazine derivatives were shown to be effective as selective COX-2 inhibitory activity. Others exhibited a preferential inhibition of COX-2, although some COX-1 inhibitory activity was still present. As a conclusion, simple monomer derivatives were more active than dimer derivatives. Substitution of halogen (Br, C1) on the benzothiazine nucleus slightly enhanced inhibition activity.

• Textile Coloration and Finishing
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• v.10 no.4
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• pp.53-61
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• 1998

The absorptions of ultraviolet rays of benzophenone derivatives were investigated in terms of the position of substituent, especially hydroxyl group. When the derivatives were added to the aqueous solution of Rhodamin B, which has very low light-fastness, all of them delayed the photofading of Rhodamin B solution. But on the fabrics, only the derivatives with the hydroxyl group at 2-position showed the good ability of ultraviolet rays absorption. The benzophenone derivatives absorb ultraviolet rays to form a hydrogen bond between hydroxyl group and carbonyl group, and return to their original structure by releasing heat energy. In solution, the derivatives can form a intermolecular hydrogen bond, and absorb the ultraviolet rays. But on the fabric, the intermolecular hydrogen bond is impossible, only hydroxyl group of 2-position forms a intramolecular hydrogen bond, and that makes the derivatives on the fabric absorb ultraviolet rays.

• Journal of Ship and Ocean Technology
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• v.3 no.3
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• pp.25-44
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• 1999

Estimation efficiencies according to different sea trial are investigated in connection with sensitivity analysis, and new trial method is proposed which can improve the estimation efficiency of hydrodynamic derivatives. MMG Equation with Kijima's formula is used for simulation. Extended Kalman Filter is chosen for estimation technique and hydrodynamic derivatives of interest is limited to 12 of those in sway and yaw equations. Esso Osaka is selected for the test ship. Sensitivity analysis and estimation results based on conventional trials show that a more sensitive derivative gives more efficient estimation result. Sensitivities of nonlinear derivatives become pronounced in the trial where steady condition lasts longer such as turning test, while sensitivities of linear derivatives gas a larger values in the trial where unsteady condition lasts longer such as 10deg-10deg zigzag test. Consequently, in new method , named S-type trial, steady and unsteady condition are combined appropriately to increase sensitivities. Linear derivatives are estimated better in S-type trial and the estimation of nonlinear derivatives is improved to extent.

• Journal of the Korean Wood Science and Technology
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• v.22 no.4
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• pp.51-60
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• 1994

Chlorodeoxycellulose derivatives have recently assumed importance since the halogen atoms can be changed with other functional groups to afford new derivatives of cellulose. Also, chlorinated cellulose has been employed as an intermediate in the preparation of various functional cellulose derivatives. In this study chlorodeoxycellulose was prepared by reaction of methylcellulose with mathanesulfonylchloride in N,N-dimethylformamide. Subsequently, conversion of the above chlorinated cellulose to unsaturated celluloseen was carried out by potassium tertiary butoxide in dimethyl sulfoxide. An anhydrocellulose as an intermediate for the reactive functional derivatives was made by simple alkali treatment. Preparation condition of allylated methylcellulose by using allylchloride and its thermal behavior were also described.

• Archives of Pharmacal Research
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• v.12 no.3
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• pp.181-185
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• 1989

When 3-acetyl coumarin derivatives are treated with bromine, 3-(w-bromoacetyl) coumarin derivatives are obtained. The reaction of 3-(w-bromoacetyl)coumarin derivatives with thiourea or with amines for two hours leads to the formation of 2-Amino-4-(3-coumarinyl) thiazole or 3-(w-aminoacetyl) coumarin derivatives, respectively. While 3-(w-bromoacetyl) coumarin derivatives react with amines for 5-8 hours to yield imino derivatives of 3-(w-aminoacetyl) coumarin. The antimicrobial activity of Ia-b, IIa-c, IVc-f, IVh and V$_{c}$, f, h, k, m, and q was studied.d.

• Archives of Pharmacal Research
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• v.16 no.1
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• pp.62-67
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• 1993

A series of 12 pyrimidine derivatives were prepared and tested in vitro against growth, sporulation and nucleic acids of Fusarium oxysporum f. sp. lycopersici and Helminthosporium oryzae. Intorduction of thiazole ring together with two aryl groups to 2-aminopyrimidine induced drastic toxicity for both fungi. Pyrimidine derivatives with aryl groups were less toxic. Nitro groups were found to enhance the toxicity of the pyrimidine derivatives especially when substituted in ortho-position of the aryl groups. Inhibition of nudeic acids synthesis of both fungi was attributed mainly to the presence of thiazole ring.

• YAKHAK HOEJI
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• v.46 no.6
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• pp.375-380
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• 2002

In this study, newly designed COX-2 inhibitors, synthetic derivatives of benzothiazine-3-carboxamide, were screened in vitro for selectivity of COX-1 and COX-2 inhibition properties. 7-Bromo-1,2-benzoisothiazine derivatives were obtained from 4-bromotoluene over the chlorosulfonation, amination and oxidation. And benzothiazine ring was synthesized through Gabriel-Colmann rearrangement reaction. To evaluate inhibitory effect of COX-2, synthetic derivatives of benzothiazine-3-carboxamide were tested with accumulation of prostaglandin by lipopolysaccharide in aspirin-treated murine macropharge cell. Some of the synthesized lead compounds have potentially shown the structure-activity relationship for selectivity of COX-2 inhibition activity.

• Biomolecules & Therapeutics
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• v.8 no.1
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• pp.1-12
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• 2000

Although the first pyridazine was obtained in 1886, this heterocycle was not thoroughly investigated such isomers as pyrimidine and pyrazine especially in the field of drug development because pyridazine derivatives do not occur as natural products. Recently medicinal chemists have an growing interest in the pyridazine derivatives, since many Pyridazine derivatives were found to possess various potential therapeutic activities. In this paper sixty-eight pyridazine derivatives, which are already introduced as medicines or are being developed as drugs were classified according to their pharmacological activities, reviewed since 1955 and the relationship of structure-activities was discussed.

• YAKHAK HOEJI
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• v.29 no.5
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• pp.253-259
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• 1985

In order to search a more active and safer compound, piperine derivatives with substituents in piperidine residue were synthesized and evaluated on CNS depressant activity. N-Piperoyl-2-methylpiperidine (I) and N-piperoyl-3-methylpiperidine (II) were potent in strychnine-induced convulsion. Compound I and N-piperoyl-3-hydroxypiperidine (IX) exhibited a potent inhibitory effect againt pentetrazoleinduced convulsion and a significant prolongation effect of hexobarbital-induced sleeping time. The hydroxy derivatives were more toxic than the methyl derivatives.

• YAKHAK HOEJI
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• v.55 no.5
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• pp.367-373
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• 2011

It was reported that the potency of TMMC derivatives was related to the presence of the 2'-hydroxy group on the A ring. Also, 4-dimethylamino group on the B ring lowered the anti-inflammatory potency of the chalcones. We synthesized various derivatives of 2'-hydroxy chalcones having other substituents on B ring. The synthetic derivatives showed the more potent anti-inflammatory effect, comparable to that of the TMMC derivatives reported previously.