• Archives of Pharmacal Research
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• v.29 no.12
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• pp.1119-1124
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• 2006

The methanol extract from the aerial parts of Dictamnus albus was active in inhibiting monoamine oxidase (MAO) from the mouse brain. Activity-guided fractionation led to the isolation of four known coumarins, 7-(6'R-hydroxy-3', 7'-dimethyl-2'E, 7'-octadienyloxy) coumarin (1), auraptene (2), umbelliferone (3), and xanthotoxin (4), as active compounds along with an inactive alkaloid, skimmianine (5). Compounds 1 and 2 inhibited MAO activity in a concentration-dependent manner with $IC_{50}$ values of 0.7 and $1.7\;{\mu}M$, respectively. Compounds 1 and 2 showed a slight and potently selective inhibitory effect against MAO-B ($IC_{50}\;0.5\;and\;0.6\;{\mu}M,\;respectively$) compared to MAO-A ($IC_{50}\;1.3\;and\;34.6\;{\mu}M,\;respectively$). According to kinetic analyses derived by Lineweaver-Burk reciprocal plots, compounds 1 and 2 exhibited a competitive inhibition to MAO-B.

• Journal of Marine Bioscience and Biotechnology
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• v.2 no.4
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• pp.209-223
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• 2007

Nature is one of the most important sources of pharmacologically active compounds in the search for drugs against life threatening diseases. Even though plants and terrestrial microorganisms have played as an important source for the new drug candidates from nature, marine organisms such as tunicates, sponges, soft corals, sea horses, sea snakes, marine mollusks, seaweeds, nudibranches, sea slugs and marine microorganisms are increasingly attracting attention in recent years. Marine organisms also have the potential to develop into future drugs against important diseases, such as cancer, a range of bacterial and viral diseases, malaria, and inflammations. Even though the mechanism of action in the molecular level of most metabolites is still unclear, the mechanisms by which they interfere with the pathogenesis of a wide range of diseases have been reported. The knowledge of this is one of the key factors necessary to develop bioactive compounds into medicines. This is due to their structurally unique and pharmacologically active compounds. The potential pharmaceutical, medicinal and research applications of some of these compounds are discussed in hundreds of scientific papers, and are reviewed here.

• Archives of Pharmacal Research
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• v.28 no.8
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• pp.892-896
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• 2005

In order to isolate substances that inhibit the hemolytic activity of human serum against eryth-rocytes, we have evaluated whole plants of the Orostachys japonicus species with regard to its anti-complement activity, and have identified its active principles following activity-guided isolation. A methanol extract of the O. japonicus, as well as its n-hexane soluble fraction, exhibited significant anti-complement activity on the complement system, which was expressed as total hemolytic activity. A bioassay-guided chromatographic separation of the constituents resulted in the isolation of three known compounds 1-3 from the active n-hexane fraction. The structure of these compounds were analyzed, and they were identified as hydroxyhopanone (1), $\beta-sitosteryl-3-O-\beta-D-glucopyranosyl-6'-O-palmitate$ (2), and $\beta-sitosteryl-3-O-\beta-D-glucopyranoside$ (3), respectively. Of these compounds, compound 2 exhibited potent anti-complement activity $(IC_{50}=1.0\pm0.1{\mu}M)$ on the classical pathway of the complement, as compared to tiliroside $(IC_{50}=76.5\pm1.1{\mu}M)$, which was used as a positive control. However, compounds 1 and 3 exhibited no activity in this system.

• Journal of Ginseng Research
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• v.48 no.1
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• pp.59-67
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• 2024

Background: Alzheimer's disease (AD) has memory impairment associated with aggregation of amyloid plaques and neurofibrillary tangles in the brain. Although anti-amyloid β (Aβ) protein antibody and chemical drugs can be prescribed in the clinic, they show adverse effects or low effectiveness. Therefore, the development of a new drug is necessarily needed. We focused on the cognitive function of Panax ginseng and tried to find active ingredient(s). We isolated panaxcerol D, a kind of glycosyl glyceride, from the non-saponin fraction of P. ginseng extract. Methods: We explored effects of acute or sub-chronic administration of panaxcerol D on cognitive function in scopolamine- or Aβ_25-35 peptide-treated mice measured by several behavioral tests. After behavioral tests, we tried to unveil the underlying mechanism of panaxcerol D on its cognitive function by Western blotting. Results: We found that pananxcerol D reversed short-term, long-term and object recognition memory impairments. The decreased extracellular signal-regulated kinases (ERK) or Ca²⁺/calmodulin-dependent protein kinase II (CaMKII) in scopolamine-treated mice was normalized by acute administration of panaxcerol D. Glial fibrillary acidic protein (GFAP), caspase 3, NF-kB p65, synaptophysin and brainderived neurotrophic factor (BDNF) expression levels in Aβ_25-35 peptide-treated mice were modulated by sub-chronic administration of panaxcerol D. Conclusion: Pananxcerol D could improve memory impairments caused by cholinergic blockade or Aβ accumulation through increased phosphorylation level of ERK or its anti-inflammatory effect. Thus, panaxcerol D as one of non-saponin compounds could be used as an active ingredient of P. ginseng for improving cognitive function.

• Archives of Pharmacal Research
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• v.29 no.9
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• pp.741-745
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• 2006

In our efforts to discover novel phytoestrogens to treat menopausal symptoms, eleven furanocoumarins were isolated from Angelica dahurica and tested for their estrogenic activity on the Ishikawa cell line. Among the compounds tested, 9-hydroxy-4-methoxypsoralen and alloisoimperatorin showed strong abilities to induce alkaline phosphatase (AP) with $EC_{50}$ values of 1.1 and $0.8\;{\mu}g/mL$, respectively, whereas the other nine furanocoumarins were weakly or only slightly active.

• Bulletin of the Korean Chemical Society
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• v.30 no.3
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• pp.687-690
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• 2009

A series of novel 1,3-diallyltrisulfane analogues were synthesized and assayed in vitro for antimicrobial activity against Gram positive, Gram negative bacteria and fungi. The antimicrobial activity of the 1,3-diallyltrisulfane derivatives showed, on the whole, very potent towards all the tested Gram positive, Gram negative and fungi (MIC ranging from 4 to 256 μg/mL). 1,3-Di(pent-4-enyl)trisulfane 3b and 1,3-bis(3-methylbut-2-enyl)trisulfane 3e exhibited the strongest antibacterial activity among all the compounds, and both of them were more active than 1,3-diallyltrisulfane (DATS). Results indicated the relationship of either carbon number or lipophilicity with antimicrobial activity presented “V” shape. These observations provided some predictions in order to further design 1,3-diallyltrisulfane derivatives with antimicrobial activity.

• Proceedings of the PSK Conference
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• 2002.10a
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• pp.347.3-347.3
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• 2002

Recent study indicated that terpyridine and its derivatives displayed highly active antitumor properties. In this presentation. derivatives of terpyridines having three pyridine moieties at 2',4',6'-position of central pyridine skeleton were prepared, and evaluated their cytotoxicity against several human cancer cell lines and topoisomerase I inhibitory activities. Most of the prepared compounds showed strong cytotoxicity compared to doxorubicln. In addition. several compounds displayed better cytotoxicity than that of doxorubicin. In addition, several compounds displayed better cytotoxicity than that of doxorubicin. Structure-activity relationship study was perfomed to be indicated that [2.2':6',2']terpyidine skeleton is important to show strong xytotoxicity. Significant topoxicity. Significant topoisomerase I inhibitory activity was not observed for prepared compounds.

• Mass Spectrometry Letters
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• v.6 no.3
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• pp.65-70
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• 2015

N-Alkyl/benzyl substituted isatin derivatives are intermediates and synthetic precursors for the preparation of biological active heterocycles. N-alkyl/benzyl isatins have showed various biological activities, such as cytotoxicity, antiviral, caspase inhibition, cannabinoid receptor 2 agonists for the treatment of neuropathic pain, etc. In this study, N-alkyl/benzyl isatin derivatives were synthesized from isatin and alkyl/benzyl halides in presence of K₂CO₃ in DMF and excellent to quantitative yields (~95%) were obtained. Isatins and benzyl-isatins were condensed with fluorescein hydrazide to form fluorescein hydrazone. All the compounds were subjected to their fragmentation behavior study using LC/MSⁿ. N-Alkyl substituted isatin derivatives fragmented at nitrogen-carbon (N-C) bond, hence gave daughter ion as [RN+H]⁺. Whereas, N-benzyl substituted isatin derivatives fragmented at carbon-carbon (C-C) bond of alkyl chain which linked with nitrogen molecules, therefore gave N-methyl fragments [RNCH₂]⁺. This study demonstrated that, isatin moiety present in a small/large molecule or in a matrix of reaction mixture with/without N-alkyl/benzyl substituents can be identified by mass spectroscopic fragmentation behavior study.

• YAKHAK HOEJI
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• v.38 no.3
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• pp.322-331
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• 1994

For the development new cephalosporin antibiotics with aminothiazolmethoxyimino moiety in the C-7 position and triazolthiomethyl moiety in the C-3 position of cephem ring, $7{\beta}$-[(z)-2-(2-aminothiasol-4-yl)-2-(methoxyimino)acetamido]-3-[5-(aryl or het.)-4-phenyl-4H-1,2,4-triazol-3-yl]thiomethyl-3-cephem-4-carboxylic acids were synthesized. These compounds were tested for antimicrobial activitiy in vitro against ten species of microorganisms. It showed remarkable antibacterial activity against Bacillus subtilis ATCC 6633, Micrococcus luteus ATCC 9341 and Escherichia coli ESS. The antibacterial activity of most new compounds showed more active than cefazoline, but these compounds were lower active than cefotaxime against Pseudomonas aeruginosa IFO 13130.

• YAKHAK HOEJI
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• v.49 no.5
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• pp.428-436
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• 2005

DNA topoisomerase I(TOP1) helps the control of DNA replication, transcription and recombination by assist­ing breaking and rejoining of DNA double strand. Camptothecin (CPT) and its derivative, topotecan, are known to inhibit TOP1 by intercalating into TOP1-DNA complex. Recently various non-CPT intercalators are synthesized for a new class of TOP1 inhibitors. In this study, six compounds isolated from Poria cocos were investigated for their interaction with TOP1­DNA complex using the flexible docking program, FlexiDock. The binding modes were analyzed and compared with the TOP1 inhibition activities. The compounds that showed potent activity were intercalated between the + 1/-1 base pairs of DNA, located near the active site phosphotyrosine723 and formed hydrogen bonds with active site residues. On the other hand, compounds with no activity were not docked at all. The binding modes were well correlated with the inhibition activity, suggesting the possibility that potent inhibitors can be designed from the information presented by the docking study.