• Archives of Pharmacal Research
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• v.20 no.3
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• pp.264-268
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• 1997

In order to study the structure-activity relationship of 7, 8-dimethoxy-2-methyl-3-(4, 5-methylenedioxy-2-vinylphenyl)isoquinoline-1(2H) -one (2), which has exhibited significant antitumor activity, chemical modifications of 2 were performed to yield the corresponding products (3-7). Further systematic uses of an efficient procedure for the synthesis of 3-arylisoquinoline derivatives produced the substituted compounds (9a-9g), which were tested for in vitro antitumor activity against five different human cancer cell lines.

• Journal of Evidence-Based Herbal Medicine
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• v.3 no.1
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• pp.35-41
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• 2010

From the roots of Angelica dahurica Bentham et Hooker (Umbelliferae), three known coumarin derivatives have been isolated and identified as 8-(2-hydroxy-3-methoxy-3-methylbutyloxy) psoralen, 5,8-di(2,3-dihydroxy-3-methylbutyloxy) psoralen, 9-[3-($\beta$-D-glucopyranosyloxy)-2-hydroxy-3-methylbutoxy]-7H-furo[3,2-g][1]benzopyran-7-one. This is the first report of the occurrence of these compounds in this plant. These three compounds were tested for activity in septic shock model. Among these compounds, 2 showed relatively strong preventive activity against septic shock.

• Bulletin of the Korean Chemical Society
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• v.7 no.1
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• pp.45-50
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• 1986

Separation of optical isomers of some derivatives of amino acids by reversed-phase HPLC has been accomplished by adding a chelate of an optically active amino acid to copper(Ⅱ) to the mobile phase. Cu(Ⅱ) complexes of L-proline and L-hydroxyproline in the mobile phase showed different degrees of separation. Optical isomers of DNS derivatives of amino acids are selectively separated, but those of several other derivatives are not at all. The kinds of buffer agents, the pH, and the concentrations of acetonitrile and the Cu(Ⅱ) ligand all affect the separations. The elution behavior between D and L DNS-amino acids appears to depend on the alkyl side chain of the amino acids. A chromatographic mechanism is proposed that is based on a stereospecificity of the formation of ternary complexes by the D, L-DNS-amino acids and the chiral additive associated with the stationary phase. The steric effects of the ligand exchange reactions are related with the feasibility of cis and/or trans attack of the amino acids to the binary chiral chelate retained on the stationary phase.

• Structural Engineering and Mechanics
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• v.7 no.6
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• pp.561-573
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• 1999

A $C^*$-convergence algorithm for finite element analysis has been proposed by Bigdeli and Kelly (1997) and elements for the first three levels applied to planar elasticity have been defined. The fourth level element for the new family is described in this paper and the rate of convergence for the $C^*$-convergence algorithm is investigated numerically. The new family adds derivatives of displacements as nodal variables and the number of nodes and elements can therefore be kept constant during refinement. A problem exists on interfaces where the derivatives are required to be discontinuous. This problem is addressed for curved boundaries and a procedure is suggested to resolve the excessive interelement continuity which occurs.

• Journal of the Korean Applied Science and Technology
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• v.7 no.2
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• pp.33-40
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• 1990

The Kinetics of the addition of benzalacetophenone derivatives was investigated by ultraviolet spectrophotometery in 5% dioxane $H_2O$ at $50^{\circ}C$. A rate equation was obtained in wide range of pH. The substituent effects on benzalacetophenone derivatives were studied, and addition were facilitated by electron attracting groups. The final product was benzalacetophenone-${\beta}$-thioglycolic acid synthesized by the addition of thioglycolic acid to benzalacetophenone. On the base of the rate equation, substituent effect, general base effect and final product, the plausible addition mechanism was proposed: Below pH 9.0, only neutral thioglycolic acid molecule was added to the carbon-carbon double bond, and in the range of pH $9.0{\sim}11.0$, neutral thioglycolic acid molecule and thioglycolic acid anion competitively attacted the double bond. By contrast, above pH 11.0, the reaction was dependent upon only the addition of thioglycolic acid anion.

• Journal of the Korean Chemical Society
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• v.31 no.5
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• pp.464-470
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• 1987

7-Substituted 2-aminophenazine-5,10-dioxides were synthesized by the reaction of 4-aminophenol with 6-substituted benzofuroxan derivatives which had been obtained from aniline derivatives bearing methoxy, methyl, acetyl, and nitro group at the para position. 2-Aminophenazine-5,10-dioxide was also prepared by the reaction of 4-aminophenol with benzofuroxan. The antimicrobial activities of these phenazine dioxide derivatives were investigated in terms of minimum inhibitory concentration by the common twofold dilution technique. It was observed that the antimicrobial activity of the phenazine dioxides bearing electron releasing substituents was stronger than that of those bearing electron withdrawing substituents. From this result, it was concluded that the antimicrobial activity of phenazine dioxide derivative has a direct relationship with the electronic effect of the substituents.

• Biomolecules & Therapeutics
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• v.14 no.2
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• pp.102-105
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• 2006

We examined the effects of psoralen derivatives on a rapidly activating delayed rectifier $K^+$ channel (hKv1.5) cloned from human heart and stably expressed in $Ltk^-$ cells. Using the whole cell configuration of the patch-clamp technique, we found that the five psoralen derivatives inhibited hKv1.5 current. Especially, 4-(2-Propenyloxy)-7H-furo[3,2-g][1]benzopyran-7-one (compound 5) was more potent than the inhibition of the hKv1.5 current of psoralen. The compound 5 inhibited the hKv1.5 current in a concentration-, time-, and voltage-dependent manner. These results suggest that the compound 5 is an excellent candidate as an antiarrhythmic drug for atrial fibrillation.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.12 no.7
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• pp.2982-2990
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• 2011

The puporse of this research is to analyze the impacts of derivatives to firm value. The sample of this research consists of 20 domestic life insurance companies and the duration of the research is the year between 2002 and 2009. And multi-regression analysis by cross-sectional analysis approach is used for the entire sample in this study. The result of the research indicates the impact of derivatives use on the value of the firm, which was the original focus of this study, is insignificant. And firm value increases as the leverage, rate of return on a loan, the ratio of product for annuity and the ratio of expense decrease.

• Applied Biological Chemistry
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• v.27 no.2
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• pp.95-99
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• 1984

Some derivatives of 3-oxo-1,2-benzisothiazole-1,1-dioxide were synthesized, and their antifungal activities against Pyricularia oryzae was determined by the agar medium dilution method. $I_{50}$ values of the candidate derivatives were shown to be as follows; 3-chloro(37.8ppm), 2-chloro(318.7ppm), MCS(20.1ppm), 2-allyl(946.2ppm), 3-(p-nitrophenyloxy) (35.4ppm), 3-(o-nitrophenyloxy) (11.8ppm), 3-(p-aminophenyloxy) (1643.2ppm), 2-chloromethyl(192.7ppm) and 2-hydroxymethyl derivative(248.4ppm).

• YAKHAK HOEJI
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• v.36 no.5
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• pp.440-448
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• 1992

7-Substituted 2,3-dihydroxyphenazine 5,10-dioxides were synthesized by the reaction of 1,2,4-trihydroxybenzene with 6-substituted benzofuroxan derivatives which had been obtained from aniline derivativies bearing methoxy, methyl, acetyl and nitro group at the para position. 2,3-Dihydroxyphenazine 5,10-dioxide was also prepared by the reaction of 1,2,4-trihydroxybenzene with benzofuroxan. The antimicrobial activities of these phenazine dioxide were investigated in terms of minimum inhibitory concentration by the common twofold dilution technique. It was observed that the antimicrobial activity of the phenazine dioxides bearing electron releasing substituents was stronger than that of those bearing electron withdrawing substitutents. From this result, it was concluded that the antimicrobial activity of phenazine dioxide derivatives has a direct relationship with the electronic effect of the substituents.