• Proceedings of the PSK Conference
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• 2002.04a
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• pp.199.1-199.1
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• 2002

• Archives of Pharmacal Research
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• v.22 no.5
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• pp.507-514
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• 1999

6-(1-azidoalkyl)-DMNQ derivatives compared to 2-(1-azidoalkyl)-DMNQ isomers, exhibited higher cytotoxic activity against L1210 mouse leukemia cells and stronger inhibition of DNA topoisomerase-I (TOPO-I), suggesting involvement of steric hindrance. However, similar antitumor activity against mice bearing S-180 cell was shown by 2-an 6-(1-azidoalkyl)-DMNQ derivatives.

• YAKHAK HOEJI
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• v.46 no.5
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• pp.295-300
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• 2002

To observe the structure-activity relationship of lupane derivatives both on cytotoxic and antiangiogenic activity, twelve lupane derivatives were prepared; their antiangiogenic and cytotoxic activities were evaluated. Among them, four compounds were more cytotoxic than betulinic acid. Carboxylic acid at C28 seemed to be essential for cytotoxic activity. But, a selective cytotoxicity toward SK-MEL-2 was not observed. As for antiangiogenic activity, none of the compounds except lupeol showed antiangiogenic activity at 30 $\mu\textrm{g}$/mL.

• Bulletin of the Korean Chemical Society
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• v.20 no.9
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• pp.1073-1077
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• 1999

CRAMP, a 37-amino acid cationic antimicrobial peptide was recently deduced from the cDNA cloned from mouse femoral marrow RNA. In order to investigate the structure-activity relationship and functional region of CRAMP, CRAMP and its 18-mer overlapping peptides were synthesized by the solid phase method. CRAMP showed broad spectrum antibacterial activity against both Gram-positive and Gram-negative bacterial strains (MIC: 3.125-6.25 μM) but had no hemolytic activity until 50 μM. CRAMP was found to have a potent anticancer activity (IC50: 12-23 μM) against two human small cell lung cancer cell lines. Furthermore, CRAMP was found to display faster bactericidal rate in B. subtilis rather than E. coli in the kinetics of bacterial killing. Among 18-meric overlapping fragment peptides, only CRAMP (16-33) displayed potent antibacterial activity (MIC: 12.5-50 μM) against several bacteria with no hemolytic activity. Circular dichroism (CD) spectra anal-ysis indicated that CRAMP and its analogues will form the amphipathic α-helical conformation in the cell membranes similar to other antimicrobial peptides, such as cecropins and magainins.

• Biomolecules & Therapeutics
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• v.32 no.4
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• pp.442-450
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• 2024

The type-1 cannabinoid receptor (CB₁R) is a potential therapeutic target in several pathological conditions, including neuropsychological disorders and neurodegenerative diseases. Owing to their structural diversity, it is not easy to derive general structure-activity relationships (SARs) for CB₁R ligands. In this study, CB₁R ligands were classified into six structural families, and the corresponding SAR was determined for their affinities for CB₁R. In addition, we determined their functional activities for the activation of extracellular signal-regulated kinases (ERKs). Among derivatives of indol-3-yl-methanone, the highest ligand affinity was observed when a pentyl and a naphthalenyl group were attached to the N1 position of the indole ring and the carbon site of the methanone moiety, respectively. In the case of adamantane indazole-3-carboxamide derivatives, the presence of fluorine in the pentyl group, the substituent at the N1 position of the indazole ring, strongly increased the affinity for CB₁R. For (naphthalen-1-yl) methanone derivatives, the presence of 4-alkoxynaphthalene in the methanone moiety was more beneficial for the affinity to CB₁R than that of a heterocyclic ring. The functional activities of the tested compounds, evaluated through ERK assay, were correlated with their affinity for CB₁R, suggesting their agonistic nature. In conclusion, this study provides valuable insight for designing novel ligands for CB₁R, which can be used to control psychiatric disorders and drug abuse.

• Korean Journal of Food Science and Technology
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• v.51 no.4
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• pp.336-342
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• 2019

To elucidate structure-function relationship of polysaccharide from Angelica gigas, the AGE-2c-I was purified by two successive chromatography steps. AGE-2c-I showed a potent anti-complementary activity in a dose-dependent manner. AGE-2c-I with a molecular weight of 140 kDa comprised four monosaccharides and 13 glycosyl linkages, and strongly reacted with ${\beta}$-glucosyl Yariv reagent. For the fine structure analysis of AGE-2c-I, it was sequentially digested by exo-arabinofuranosidase and endo-galactanase. The results indicated that AGE-2c-I was a typical RG-I polysaccharide with side chains such as highly branched ${\alpha}$-arabinan, ${\beta}$-($1{\rightarrow}4$)-galactan and arabino-${\beta}$-3,6-galactan. To characterize the active moiety of AGE-2c-I, the anti-complementary activities of AGE-2c-I and its subfractions were assayed. It was observed that the anti-complementary activity of AGE-2c-I was due to the entire structure that resembled RG-I. In addition, arabino-${\beta}$-3,6-galactan side chain (GN-I) in AGE-2c-I probably plays a crucial role in the anti-complementary activity, whereas ${\alpha}$-arabinan side chain (AFN-I) consisting of 5-linked Araf and 3,5-branched Araf partially contributes to the activity.

• Environmental Mutagens and Carcinogens
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• v.21 no.2
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• pp.113-117
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• 2001

The screening of various molecular descriptors for predicting carcinogenic, mutagenic and teratogenic activities of chlorinated aliphatic compounds as drinking water disinfection byproducts (DBPs) has been investigated for the application of quantitative structure-activity relationships (QSAR). The present work embodies the study of relationship between molecular descriptors and toxicity parameters of the genotoxicity endpoints for the screening of relevant molecular descriptors. The toxicity Indices for 29 compounds constituting the testing set were computed by the PASS program and active values were chosen. We investigate feasibility of screening descriptors and of their applications among different genotoxic endpoints. The correlation to teratogenicity of all 29 compounds was significantly improved when the same analysis was done with 20 alkanes only without alkene compounds. The HOMO (highest occupied molecular orbital) energy and number of Cl parameters were dominantly contributed.

• The Journal of the Korea Contents Association
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• v.7 no.10
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• pp.115-125
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• 2007

This study analyzed the importance of user activity, communication between users and identity establishment by growth and change of player's character through users' communication structure and then it classified such an importance into activity by group, dealings, information sharing, duel and strategy performance. It also looked into the plans to revitalize smooth social relationship and suggested for users to behave with responsibility in virtual society. In the virtual space where thousands of people connect and interact with each other every day, users find out their identities through human relationship with others proceeding solo story. What is more important is that users consider virtual space as a society and feel collective responsibility on words and behavior against others.

• Environmental Analysis Health and Toxicology
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• v.24 no.2
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• pp.79-93
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• 2009

오염물질에 대한 생태위해성평가(ecological risk assessment)를 위해서는 노출평가(exposure assessment)와 함께 생물영향에 대한 평가(effect assessment)를 수행해야 한다. 노출평가의 경우는 지화학적 과정에 대한 이해를 바탕으로 환경농도를 예측하기 위한 화학평형모델이나 다매체환경거동모델 등 다양한 평가 및 예측모델을 활용해 왔다. 이와 달리 생물영향평가는 실험실 조건에서 제한된 독성자료를 대상으로 외부노출농도에 기반한 농도-반응관계를 통계적 방법을 통해서 추정하는 '경험적 모델(empirical model)'에 주로 의존해 왔다. 최근에 와서 생체 내 잔류량을 기반으로 농도-시간-반응관계를 기술하고 예측하는 독성동태학 및 독성역학 모델(toxicokinetic-toxicodynamic model)과 같은 독성작용에 기반한 모델(processbased model)들이 개발되어 활용되고 있다. 본 논문에서는 여러 종류의 독성동태학 및 독성역학 모델을 소개하고, 이를 통계적 추론에 기반한 전통적인 독성학 모델과 비교하였다. 서로 다른 종류의 독성동태학 및 독성역학 모델로부터 도출된 노출농도-시간 -반응관계식을 비교하고, 동일 독성기작을 보이는 오염물질 그룹 내에서 미측정 오염물질의 독성을 예측할 수 있게 해주는 구조-활성관계(Quantitative Structure-Activity Relationship, QSAR) 모델을 여러 독성동태 및 독성역학모델로부터 유도하였다. 마지막으로 독성동태학 및 독성역학 파라미터를 추정하기 위한 실험계획을 제안하였고, 앞으로 독성동태학 및 독성역학 모델을 생태계 위해성평가에 활용하기 위해서 해결해야 될 연구과제를 검토하였다.

• Biomolecules & Therapeutics
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• v.17 no.1
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• pp.79-85
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• 2009

Polyphenolic compounds are reported to have various pharmacological activities such as anti-oxidative, anti-cancerous, anti-inflammatory and anti-aging effects. Although numerous papers explore their functional roles in many different cellular actions, not many studies handle their structural features in anti-inflammatory responses. In this study, therefore, we examined structural role of substituted transstilbenes in their NO inhibitory and NF-${\kappa}B$ suppressive activities. Of 10 compounds tested, 4 compounds (cinnamic acid, resveratrol, piceatannol and curcumin) displayed NO inhibitory activities in a dose-dependent manner. Similarly, these compounds blocked LPS-induced cytotoxicity of RAW264.7 cells. All NO inhibitory compounds also inhibited $I{\kappa}B{\alpha}$ phosphorylation, a hallmark for NF-${\kappa}B$ activation. However, these inhibitory compounds exhibited distinct suppressive pattern in tumor necrosis factor (TNF)-${\alpha}$- or phorbol-12-myristate-13-acetate (PMA)-induced NF-${\kappa}B$ and AP-1 activation. According to structure-activity relationship study, polarity and size of ring B seem to be important for diminishing NO production. Therefore, our data suggest that substituted trans-stilbenes can be developed as novel anti-inflammatory drug or further developed as lead compounds for another improvement.