47 results on '"Dongho Lee"'
Search Results
2. Plasma-Induced Selective Propylene Epoxidation Using Water as the Oxygen Source
- Author
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Dongho Lee, Han-Ting Chen, and Suljo Linic
- Published
- 2023
3. Molecular Networking-Guided Isolation of Cycloartane-type Triterpenoids from Curculigo orchioides and Their Inhibitory Effect on Nitric Oxide Production
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Jun Gu Kim, Thi Phuong Linh Le, Jae Sang Han, Yong Beom Cho, Dongho Lee, Mi Kyeong Lee, and Bang Yeon Hwang
- Subjects
General Chemical Engineering ,General Chemistry - Published
- 2022
4. Methylammonium Compensation Effects in MAPbI3 Perovskite Solar Cells for High-Quality Inorganic CuSCN Hole Transport Layers
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Gisung Kim, Namhee Kwon, Dongho Lee, Mijoung Kim, Moonhoe Kim, Yongjei Lee, WooJong Kim, Daseul Hyeon, Bora Kim, Mun Seok Jeong, Jinpyo Hong, and JungYup Yang
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General Materials Science - Published
- 2022
5. Clerodane Diterpenoids Identified from Polyalthia longifolia Showing Antifungal Activity against Plant Pathogens
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Hun Kim, Minh Van Nguyen, Dongho Lee, Seung Mok Ryu, Quang Le Dang, Gyung Ja Choi, and Jae Woo Han
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Traditional medicine ,biology ,Chemistry ,food and beverages ,General Chemistry ,biology.organism_classification ,Plant disease ,chemistry.chemical_compound ,Minimum inhibitory concentration ,In vivo ,Pepper ,Polyalthia longifolia ,Blight ,Methanol ,Diterpene ,General Agricultural and Biological Sciences - Abstract
In the search for new natural resources showing plant disease control effects, we found that the methanol extract of Polyalthia longifolia suppressed fungal disease development in plants. To identify the bioactive substances, the methanol extract of P. longifolia was extracted by organic solvents, and consequently, four new 2-oxo-clerodane diterpenes (1-4), a new 4(3 → 2)-abeo-clerodane diterpene (5), together with ten known compounds (6-16) were isolated and identified from the extracts. Of the new compounds, compound 2 showed a broad spectrum of antifungal activity with moderated minimum inhibitory concentration (MIC) values in a range of 50-100 μg/mL against tested fungal pathogens. Considering with the known compounds, compound 6 showed the most potent antifungal activity with an MIC value in the range of 6.3-12.5 μg/mL. When compound 6 was evaluated for an in vivo antifungal activity against rice blast, tomato late blight, and pepper anthracnose, compound 6 reduced the plant disease by at least 60% compared to the untreated control at concentrations of 250 and 500 μg/mL. Together, our results suggested that the methanol extract of twigs and leaves of P. longifolia and its major compound 6 could be used as a source for the development of eco-friendly plant protection agents.
- Published
- 2021
6. Cytotoxic and Antiangiogenetic Xanthones Inhibiting Tumor Proliferation and Metastasis from Garcinia xipshuanbannaensis
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Shaojie Zhang, Dongho Lee, Huimei Wang, Anna-Mari Reid, Yasushi Ohizumi, Jing Xu, Yuanqiang Guo, Xuke Zhang, Jie Zhang, Namrita Lall, Chunyan Wang, Ying Li, and Ziteng Song
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Pharmacology ,biology ,010405 organic chemistry ,Chemistry ,Organic Chemistry ,Pharmaceutical Science ,Cell cycle ,biology.organism_classification ,medicine.disease ,01 natural sciences ,0104 chemical sciences ,Analytical Chemistry ,Metastasis ,HeLa ,010404 medicinal & biomolecular chemistry ,Complementary and alternative medicine ,Prenylation ,In vivo ,Apoptosis ,Drug Discovery ,medicine ,Molecular Medicine ,Cytotoxic T cell ,Cytotoxicity - Abstract
Eight prenylated xanthones including four new analogues were extracted and purified from the leaves of Garcinia xipshuanbannaensis. Multiple techniques including UV, 1D and 2D NMR, and HRESIMS were used to determine the structures of the isolated xanthones. These xanthones were evaluated for their cytotoxicity toward human cancer cells, and compound 4 exhibited activity against HeLa cells. A cytotoxic mechanism examination revealed the active compound induced cell apoptosis by arresting the cell cycle, increasing the levels of ROS, and inhibiting the expression of p-STAT3 in HeLa cells. In in vivo zebrafish experiments, compound 4 was found to block tumor proliferation and migration and have antiangiogenetic activity, and thus seems worthy of further laboratory evaluation.
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- 2021
7. Total Synthesis of the Neuroprotective Agent Cudraisoflavone J
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Qili Lu, Kyeong Lee, Dongho Lee, Yongseok Choi, Guofeng Quan, Jungsook Cho, Haeun Kwon, and Dipesh S. Harmalkar
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Stereochemistry ,Pharmaceutical Science ,Alcohol ,Moraceae ,01 natural sciences ,Neuroprotection ,Analytical Chemistry ,chemistry.chemical_compound ,Suzuki reaction ,Drug Discovery ,Cudrania tricuspidata ,Enantiomeric excess ,Pharmacology ,Molecular Structure ,010405 organic chemistry ,Organic Chemistry ,Absolute configuration ,Total synthesis ,Isoflavones ,0104 chemical sciences ,Claisen rearrangement ,010404 medicinal & biomolecular chemistry ,Neuroprotective Agents ,Complementary and alternative medicine ,chemistry ,Molecular Medicine - Abstract
Cudraisoflavone J (1), isolated from Cudrania tricuspidata, is a potent neuroprotective compound with a chiral center. Herein, we report the first total synthesis of racemic cudraisoflavone J (1) using a Claisen rearrangement and a Suzuki coupling reaction as the key steps. Racemic secondary alcohol was kinetically resolved to give (+)- and (-)-cudraisoflavone J with up to 97 and 88% enantiomeric excess, respectively. The modified Mosher's method was used to elucidate the absolute configuration of naturally occurring cudraisoflavone J.
- Published
- 2021
8. Aromatic and Aliphatic Apiuronides from the Bark of Cinnamomum cassia
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Jin Su Lee, Dongho Lee, Ji Young Kim, Suk Woo Chang, Sun Kwang Kim, Ji Hwan Lee, Jongki Hong, and Dae Sik Jang
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Syringaresinol ,Potassium ,Pharmaceutical Science ,chemistry.chemical_element ,01 natural sciences ,Analytical Chemistry ,chemistry.chemical_compound ,Cassia ,Drug Discovery ,Sugar ,Pharmacology ,chemistry.chemical_classification ,biology ,Traditional medicine ,010405 organic chemistry ,Chemistry ,Organic Chemistry ,Glycoside ,biology.organism_classification ,0104 chemical sciences ,010404 medicinal & biomolecular chemistry ,Complementary and alternative medicine ,visual_art ,visual_art.visual_art_medium ,Molecular Medicine ,Bark ,Acid hydrolysis ,Cinnamomum - Abstract
Cinnamomum cassia Presl (Cinnamon) has been widely cultivated in the tropical or subtropical areas, such as Yunnan, Fujian, Guandong, and Hainan in China, as well as India, Vietnam, Thailand, and Malaysia. Four new glycosides bearing apiuronic acid (1, 4, 6, and 7) and their sodium or potassium salts (2, 3, and 5), together with 31 known compounds, were isolated from a hot water extract of the bark of C. cassia via repeated chromatography. The structures of the new compounds (1-7) were determined by NMR, IR, MS, and ICP-AES data and by acid hydrolysis and sugar analysis. This is the first report of the presence of apiuronic acid glycosides. Some of the isolates were evaluated for their analgesic effects on a neuropathic pain animal model induced by paclitaxel. Cinnzeylanol (8), cinnacaside (9), kelampayoside A (10), and syringaresinol (11) showed analgesic effects against paclitaxel-induced cold allodynia.
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- 2021
9. Sesquiterpenoids from Chrysanthemum indicum with Inhibitory Effects on NO Production
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Thi Phuong Linh Le, Jin Woo Lee, Haeun Kwon, Bang Yeon Hwang, Dongho Lee, Yong Beom Cho, Jun Gu Kim, Jae Sang Han, and Mi Kyeong Lee
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Pharmacology ,chemistry.chemical_classification ,Circular dichroism ,biology ,010405 organic chemistry ,Chemistry ,Stereochemistry ,Organic Chemistry ,Pharmaceutical Science ,Inhibitory postsynaptic potential ,biology.organism_classification ,01 natural sciences ,Flavones ,0104 chemical sciences ,Analytical Chemistry ,Nitric oxide ,010404 medicinal & biomolecular chemistry ,chemistry.chemical_compound ,Complementary and alternative medicine ,Drug Discovery ,Ic50 values ,Molecular Medicine ,Acid hydrolysis ,Chrysanthemum indicum ,No production - Abstract
Three new guaianolide lactones (1-3) and four new 9-oxonerolidol glucosides (5-8) together with 20 known compounds were isolated from the MeOH extract of the flowers of Chrysanthemum indicum. Their structures were elucidated based on the interpretation of NMR, HRESIMS, and electronic circular dichroism (ECD) data along with acid hydrolysis. Of the isolates, sesquiterpenoids 1-4 and 15 and flavones 17 and 18 exhibited inhibitory effects on lipopolysaccharide (LPS)-induced nitric oxide production in RAW 264.7 cells with IC50 values in the range 0.2-27.0 μM.
- Published
- 2021
10. Diterpenoids and Diacetylenes from the Roots of Aralia cordata with Inhibitory Effects on Nitric Oxide Production
- Author
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Dongho Lee, Haeun Kwon, Thi Phuong Linh Le, Jin Tae Hong, Jun Gu Kim, Jin Woo Lee, Youngsoo Kim, Bang Yeon Hwang, Mi Kyeong Lee, and Jae Sang Han
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Pharmacology ,Circular dichroism ,biology ,Diacetylene ,010405 organic chemistry ,Stereochemistry ,Organic Chemistry ,Pharmaceutical Science ,biology.organism_classification ,Inhibitory postsynaptic potential ,01 natural sciences ,0104 chemical sciences ,Analytical Chemistry ,Nitric oxide ,010404 medicinal & biomolecular chemistry ,chemistry.chemical_compound ,Complementary and alternative medicine ,chemistry ,Drug Discovery ,Ic50 values ,Molecular Medicine ,Aralia cordata - Abstract
Bioactivity-guided isolation of a MeOH extract of Aralia cordata led to the isolation of four new ent-pimarane diterpenoids (1-4) and a diacetylene (5) together with 21 known compounds (6-26). Their structures were established based on the interpretation of one- and two-dimensional NMR and HRESIMS data. The absolute configurations of the new isolates were determined by electronic circular dichroism data analysis, single crystal X-ray diffraction, and Mosher's esterification method. All compounds exhibited inhibitory effects on lipopolysaccharide-induced nitric oxide production in RAW 264.7 macrophages with IC50 values ranging from 1.1 to 69.4 μM.
- Published
- 2021
11. Chemical Constituents from the Aerial Parts of Elsholtzia ciliata and Their Protective Activities on Glutamate-Induced HT22 Cell Death
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Sang Hee Shim, Young Hye Seo, Byeong Cheol Moon, Goya Choi, Dongho Lee, Seung Mok Ryu, Ki Sung Kang, Hyo Seon Kim, Jun Lee, Tuy An Trinh, and Dae Sik Jang
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Pharmacology ,Ht22 cell ,biology ,Stereochemistry ,Organic Chemistry ,Glutamate receptor ,Pharmaceutical Science ,Elsholtzia ciliata ,biology.organism_classification ,Neuroprotection ,Analytical Chemistry ,chemistry.chemical_compound ,Complementary and alternative medicine ,Glucoside ,chemistry ,Acetylation ,Drug Discovery ,Molecular Medicine ,Viability assay ,EC50 - Abstract
A new phenolic glucoside, (7E,9E)-3-hydroxyavenalumic acid-3-O-[6'-O-(E)-caffeoyl]-β-d-glucopyranoside (1), and three new acetylated flavone glycosides, acacetin-7-O-[β-d-glucopyranosyl(1″″→2″)-4‴-O-acetyl-α-l-rhamnopyranosyl(1‴→6″)]-β-d-glucopyranoside (3), acacetin-7-O-[6″″-O-acetyl-β-d-glucopyranosyl(1″″→2″)-3‴-O-acetyl-α-l-rhamnopyranosyl(1‴→6″)]-β-d-glucopyranoside (5), and acacetin-7-O-[3″″,6″″-di-O-acetyl-β-d-glucopyranosyl(1″″→2″)-4‴-O-acetyl-α-l-rhamnopyranosyl(1‴→6″)]-β-d-glucopyranoside (7), as well as 34 known compounds (2, 4, 6, and 8-38) were isolated from the aerial parts of Elsholtzia ciliata. The chemical structures of the new compounds were determined by spectroscopic/spectrometric data interpretation using NMR and HRESIMS. The neuroprotective effect of the isolated compounds was evaluated by a cell viability assay on HT22 murine hippocampal neuronal cells. Among them, 23 compounds, including new substances 1 and 3, exhibited neuroprotective effects against glutamate-induced HT22 cell death. In particular, compounds 2, 16, 17, 20, 22, 28, 29, and 31 presented potent neuroprotective effects with EC50 values of 1.5-8.3 μM.
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- 2020
12. Anti-Inflammatory ent-Kaurane Diterpenoids from Isodon serra
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Dongho Lee, Munira Abudukeremu, Jie Zhang, Jing Xu, Dihua Li, Honghong Xing, Ziteng Song, Namrita Lall, Yuanqiang Guo, Huimei Wang, Shanshan Li, Chunyan Wang, Lijun An, and Muhetaer Tuerhong
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Circular dichroism ,Stereochemistry ,medicine.drug_class ,Pharmaceutical Science ,01 natural sciences ,Anti-inflammatory ,Analytical Chemistry ,Nitric oxide ,chemistry.chemical_compound ,Drug Discovery ,medicine ,No production ,Ent kaurane ,Pharmacology ,biology ,010405 organic chemistry ,Organic Chemistry ,Isodon serra ,0104 chemical sciences ,Nitric oxide synthase ,010404 medicinal & biomolecular chemistry ,Complementary and alternative medicine ,chemistry ,biology.protein ,Molecular Medicine ,Epimer - Abstract
Ten new ent-kaurane diterpenoids, including two pairs of epimers 1/2 and 4/5 and a 6,7-seco-ent-kauranoid 10, were obtained from the aerial parts of Isodon serra. The structures of the new compounds were confirmed by extensive spectroscopic methods and electronic circular dichroism (ECD) data analysis. An anti-inflammatory assay was applied to evaluate their nitric oxide (NO) inhibitory activities by using LPS-stimulated BV-2 cells. Compounds 1 and 9 exhibited notable NO production inhibition with IC50 values of 15.6 and 7.3 μM, respectively. Moreover, the interactions of some bioactive diterpenoids with inducible nitric oxide synthase (iNOS) were explored by employing molecular docking studies.
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- 2020
13. Antioxidant and Antidiabetic Activities of Flavonoid Derivatives from the Outer Skins of Allium cepa L
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Jeong Ah Kim, Haeun Kwon, Byung Sun Min, Ngoc Khanh Vu, Quynh Mai Thi Ngo, Manh Tuan Ha, Jae Sue Choi, Dongho Lee, Se Eun Park, and Chung Sub Kim
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0106 biological sciences ,Antioxidant ,Chromatography ,biology ,Chemistry ,DPPH ,medicine.medical_treatment ,010401 analytical chemistry ,Extraction (chemistry) ,Active site ,General Chemistry ,biology.organism_classification ,Mass spectrometry ,01 natural sciences ,0104 chemical sciences ,Bulb ,chemistry.chemical_compound ,Ingredient ,biology.protein ,medicine ,Allium ,General Agricultural and Biological Sciences ,010606 plant biology & botany - Abstract
The onion, known as the bulb onion or common onion, is not only a key ingredient in many tasty and healthy vegetarian meals but also many traditional medicines. Nine new flavonoids [cepaflavas A, B (5, 6), cepadials A-D (7-9 and 14), and cepabiflas A-C (10-12)] and six known compounds (1-4, 13, 15) were obtained from the outer skins of Allium cepa L. Among them, compounds 5, 6, and 9 might be artificial products formed during extraction and isolation. New compounds were structurally elucidated using various spectroscopy/spectrometry techniques, including NMR and HRMS, and computational methods. Their absolute configurations were determined using time-dependent density functional theory calculations, combined with ECD spectroscopy, optical rotation calculation, and statistical procedures (CP3 and DP4 analysis). The free radical scavenging assays revealed that the new compounds 10-12 possessed considerable antioxidant activities with IC50 values of 4.25-8.88 and 7.12-8.14 μM against DPPH and ABTS•+, respectively. Compounds 13-15 showed substantial inhibitory activities against both α-glucosidase and protein tyrosine phosphatase 1B (PTP1B), with IC50 values of 0.89-6.80 and 1.13-6.82 μM, respectively. On the basis of molecular docking studies, 13 and 15 were predicted to have high binding capacity and strong affinity toward the active site of PTP1B.
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- 2020
14. Anti-inflammatory neo-Clerodane Diterpenoids from Ajuga pantantha
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Xuke Zhang, Muhetaer Tuerhong, Dongho Lee, Chunyan Wang, Namrita Lall, Lijun An, Munira Abudukeremu, Ling Shuai, Jing Xu, Yuanqiang Guo, Xueyuan Yang, Bangjian Dong, Wenpei Liu, and Qing Du
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Pharmacology ,Plant Components ,Circular dichroism ,biology ,010405 organic chemistry ,medicine.drug_class ,Stereochemistry ,Chemistry ,Organic Chemistry ,Pharmaceutical Science ,Nuclear magnetic resonance spectroscopy ,biology.organism_classification ,01 natural sciences ,Anti-inflammatory ,Ajuga ,0104 chemical sciences ,Analytical Chemistry ,Nitric oxide synthase ,010404 medicinal & biomolecular chemistry ,Complementary and alternative medicine ,Drug Discovery ,Ic50 values ,medicine ,biology.protein ,Molecular Medicine - Abstract
Eight new neo-clerodane diterpenoids (1-8) were acquired from the aerial parts of Ajuga pantantha. Spectroscopic data analysis permitted the definition of their structures, and experimental and calculated electronic circular dichroism data were used to define their absolute configurations. Compounds 2 and 4-8 were found to have NO inhibitory effects with IC50 values of 20.2, 45.5, 34.0, 27.0, 45.0, and 25.8 μM, respectively. The more potent compounds 2, 6, and 8 were analyzed to establish their anti-inflammatory mechanism, including regulation of the expression of inducible nitric oxide synthase (iNOS) and cyclooxygenase-2 (COX-2) proteins as well as their binding interactions with the two proteins.
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- 2020
15. Anti-inflammatory Metabolites from Chaetomium nigricolor
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Seung Mok Ryu, Min Jee Kim, Haeun Kwon, Hyuncheol Oh, Dong-Cheol Kim, Youn-Chul Kim, Dongho Lee, Seung Beom Hong, Yuanqiang Guo, and Jaeyoung Kwon
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Pharmacology ,010405 organic chemistry ,medicine.drug_class ,Chemistry ,Kinase ,Organic Chemistry ,Pharmaceutical Science ,Interleukin ,01 natural sciences ,Anti-inflammatory ,0104 chemical sciences ,Analytical Chemistry ,Nitric oxide ,010404 medicinal & biomolecular chemistry ,Enzyme activator ,chemistry.chemical_compound ,Complementary and alternative medicine ,Biochemistry ,Drug Discovery ,medicine ,Molecular Medicine ,Tumor necrosis factor alpha ,Prostaglandin E2 ,RAW 264.7 Cells ,medicine.drug - Abstract
Twelve metabolites were obtained from the culture media of Chaetomium nigricolor, including a new furan derivative, methyl succinyl Sumiki's acid (1), and two new atropisomers of the previously reported bis-naphtho-γ-pyrones, (aS)-asperpyrone A and (aS)-fonsecinone A (2 and 3). The structures were elucidated by spectroscopic, chemical, and chiroptical techniques. Compounds 2 and 3 inhibited nitric oxide production in lipopolysaccharide-stimulated RAW 264.7 macrophages. Compound 2 was found to inhibit nuclear factor-kappa B and c-Jun N-terminal kinase activation, in turn suppressing pro-inflammatory mediators and cytokines including nitric oxide, prostaglandin E2, interleukin (IL)-1β, tumor necrosis factor-α, IL-6, and IL-12.
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- 2020
16. The Role of Surface Oxygen Vacancies in BiVO4
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Dongho Lee, Giulia Galli, Patrick J. Strohbeen, Chenyu Zhou, Kyoung-Shin Choi, Mingzhao Liu, Jason K. Kawasaki, and Wennie Wang
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Materials science ,General Chemical Engineering ,Oxide ,chemistry.chemical_element ,02 engineering and technology ,General Chemistry ,Electronic structure ,Conductivity ,010402 general chemistry ,021001 nanoscience & nanotechnology ,Epitaxy ,Polaron ,01 natural sciences ,Oxygen ,0104 chemical sciences ,chemistry.chemical_compound ,chemistry ,Chemical physics ,Vacancy defect ,Bismuth vanadate ,Materials Chemistry ,0210 nano-technology - Abstract
Bismuth vanadate (BiVO4) is a widely studied oxide in solar water splitting, known for its ease of synthesis, high charge extraction yields, and advantageous band alignment with water. We present a combined first-principles and experimental study of the electronic structure of the (010) surface of BiVO4 aimed at disentangling the impact of the surface and bulk oxygen vacancies on the electronic structure and transport properties. We found that oxygen vacancies are deep donors at the surface as they are in the bulk; our calculations on defect and polaron formation energies suggest that, while polarons formed from oxygen vacancies in the bulk can contribute to conductivity, those at the surface likely do not. Our results also show that out-of-plane structural relaxations at the surface contribute to the relatively immobile nature of electron polarons derived from surface oxygen vacancies. The structural model derived from first-principles calculation was validated by comparing computed results with experimental measurements of single-crystal and epitaxially grown single-crystalline BiVO4 samples. We also found a reasonably good agreement between our calculated and measured work functions for BiVO4 samples with and without oxygen vacancies.
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- 2020
17. Clerodane Diterpenoids Isolated from the Leaves of Casearia graveolens
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Zhaohui Song, Yuanqiang Guo, Zhaoyu Shi, Jin Jin, Feng Liu, Munira Abudukeremu, Chunyan Wang, Dongho Lee, Dihua Li, Jun Ma, Muhetaer Tuerhong, Huimei Wang, Ling Shuai, Qi Zhang, and Jing Xu
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Pharmacology ,A549 cell ,Casearia ,biology ,Traditional medicine ,010405 organic chemistry ,Human lung cancer ,Chemistry ,Organic Chemistry ,Pharmaceutical Science ,biology.organism_classification ,01 natural sciences ,0104 chemical sciences ,Analytical Chemistry ,010404 medicinal & biomolecular chemistry ,Complementary and alternative medicine ,Phytochemical ,Drug Discovery ,Molecular Medicine ,Cytotoxic T cell ,Biological evaluation - Abstract
A phytochemical survey aiming to acquire pharmacologically active substances has resulted in the isolation of nine new clerodane diterpenoids, named graveospenes A-I (1-9), from the leaves of Casearia graveolens. Spectroscopic methods were employed to establish the structures with their absolute configurations being confirmed by ECD data analysis. A biological evaluation was performed, and compound 1 was found to be cytotoxic to both human lung cancer cells (A549) and human hepatocellular carcinoma cells (HepG2). A mechanism-of-action study on 1 revealed this compound to induce apoptosis of A549 cells and impede them at the G0/G1 stage.
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- 2020
18. Chemical Constituents from the Aerial Parts of Agastache rugosa and Their Inhibitory Activities on Prostaglandin E2 Production in Lipopolysaccharide-Treated RAW 264.7 Macrophages
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Dongho Lee, Seung Mok Ryu, Young Hun Seo, Sang H. Shim, Kyung-Tae Lee, Jun Lee, Shin Young Kang, A-Yeong Lee, Dae Sik Jang, Ji Sun Shin, Byeong Cheol Moon, and Goya Choi
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Lipopolysaccharide ,Stereochemistry ,Pharmaceutical Science ,Inhibitory postsynaptic potential ,01 natural sciences ,Analytical Chemistry ,chemistry.chemical_compound ,Glucoside ,Drug Discovery ,medicine ,Prostaglandin E2 ,Pharmacology ,Phenylpropanoid ,biology ,010405 organic chemistry ,Chemistry ,Organic Chemistry ,Agastache ,biology.organism_classification ,Agastache rugosa ,0104 chemical sciences ,010404 medicinal & biomolecular chemistry ,Complementary and alternative medicine ,Chemical constituents ,Molecular Medicine ,medicine.drug - Abstract
A new flavone glucoside, acacetin-7-O-(3″-O-acetyl-6″-O-malonyl)-β-d-glucopyranoside (1), two new phenolic glucosides, (3R,7R)-tuberonic acid-12-O-[6'-O-(E)-feruloyl]-β-d-glucopyranoside (14) and salicylic acid-2-O-[6'-O-(E)-feruloyl]-β-d-glucopyranoside (15), and two new phenylpropanoid glucosides, chavicol-1-O-(6'-O-methylmalonyl)-β-d-glucopyranoside (17) and chavicol-1-O-(6'-O-acetyl)-β-d-glucopyranoside(18), as well as 26 known compounds, 2-13, 16, and 19-31, were isolated from the aerial parts of Agastache rugose. The structures of the new compounds were established by spectroscopic/spectrometric methods such as HRESIMS, NMR, and ECD. The anti-inflammatory effect of the isolated compounds was evaluated by measuring their inhibitory activities on prostaglandin E2 (PGE2) in lipopolysaccharide (LPS)-treated RAW 264.7 macrophages. New compounds 1, 15, 17, and 18 inhibited LPS-induced PGE2 production with IC50 values of 16.8 ± 0.8, 33.9 ± 4.8, 14.3 ± 2.1, and 48.8 ± 4.4 μM, respectively. Compounds 5, 7, 9-11, 13, 19, 20, 22, and 27-30 showed potent inhibitory activities with IC50 values of 1.7-8.4 μM.
- Published
- 2019
19. Lignans from Saururus chinensis with Inhibitory Effects on Nitric Oxide Production
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Youngsoo Kim, Bang Yeon Hwang, Jun Gu Kim, Qinghao Jin, Jin Woo Lee, Mi Kyeong Lee, Jin Tae Hong, and Dongho Lee
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Pharmacology ,Lignan ,Organic Chemistry ,Pharmaceutical Science ,Inhibitory postsynaptic potential ,Analytical Chemistry ,Saururus chinensis ,Nitric oxide ,chemistry.chemical_compound ,Complementary and alternative medicine ,chemistry ,Drug Discovery ,Molecular Medicine ,Organic chemistry ,Carbonate ,Methanol ,No production ,Two-dimensional nuclear magnetic resonance spectroscopy - Abstract
Three biogenetically related ent-sauchinone-type lignans (1-3), four 8-O-4'-type neolignans (4-7), a diaryldimethylbutane lignan (8), and a cyclic carbonate (9), along with 12 known compounds, have been isolated from a methanol extract of the aerial parts of Saururus chinensis. The structures of the new compounds (1-9) were determined by analysis of their 1D and 2D NMR spectra, HRESIMS, and ECD data. A putative biosynthetic pathway for the three ent-sauchinone-type lignans (1-3) was postulated. Compounds 1, 7, and 10 showed inhibitory effects on LPS-induced NO production in RAW 264.7 cells with IC50 values of 5.6, 8.6, and 9.2 μM, respectively.
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- 2019
20. Xylodon flaviporus-Derived Drimane Sesquiterpenoids That Inhibit Osteoclast Differentiation
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Hak Cheol Kwon, Jong Soon Kang, Hyaemin Lee, Dongho Lee, Jae Jin Kim, Yeongseon Jang, Jaeyoung Kwon, Seung Mok Ryu, and Yuanqiang Guo
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Pharmacology ,biology ,010405 organic chemistry ,Chemistry ,Activator (genetics) ,Organic Chemistry ,Pharmaceutical Science ,Nuclear magnetic resonance spectroscopy ,Inhibitory postsynaptic potential ,biology.organism_classification ,01 natural sciences ,Molecular biology ,0104 chemical sciences ,Analytical Chemistry ,010404 medicinal & biomolecular chemistry ,medicine.anatomical_structure ,Complementary and alternative medicine ,Osteoclast ,Drug Discovery ,Ic50 values ,Flaviporus ,medicine ,Molecular Medicine ,Bone marrow ,Receptor - Abstract
The presence of excessive osteoclasts is a major factor in skeletal diseases. The present study aimed to discover osteoclast differentiation inhibitors from the basidiomycete Xylodon flaviporus. Seven new drimane sesquiterpenoids (1-7) and 7-ketoisodrimenin-5-ene (8) were obtained and characterized by various spectroscopic methods. The isolated compounds were evaluated for their inhibitory effects against receptor activator of nuclear factor-kappa-B ligand-induced osteoclastogenesis in mouse bone marrow macrophages. Compounds 1, 3, and 6 showed potent activities with IC50 values of 1.6, 0.9, and 2.1 μM, respectively, while 4, 5, and 7 exhibited relatively weak activities with IC50 values of 10.7, 10.1, and 8.5 μM, respectively.
- Published
- 2019
21. Furanocoumarins from the Roots of Angelica dahurica with Inhibitory Activity against Intracellular Reactive Oxygen Species Accumulation
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Yangkang So, Dongho Lee, Chang Hyun Jin, Eun Kyoung Seo, Ah-Reum Han, Unwoo Kang, and Seung Mok Ryu
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Pharmacology ,chemistry.chemical_classification ,Programmed cell death ,Reactive oxygen species ,Circular dichroism ,biology ,010405 organic chemistry ,Chemistry ,Stereochemistry ,Angelica dahurica ,Organic Chemistry ,Pharmaceutical Science ,Intracellular reactive oxygen species ,biology.organism_classification ,Inhibitory postsynaptic potential ,01 natural sciences ,0104 chemical sciences ,Analytical Chemistry ,010404 medicinal & biomolecular chemistry ,chemistry.chemical_compound ,Complementary and alternative medicine ,Drug Discovery ,Molecular Medicine ,Cytotoxicity ,Psoralen - Abstract
Five new furanocoumarins, dahuribirin H (1), dahuribirin I (2), (2'S)-(+)-5-(2'-hydroxy-3'-methylbut-3'-enyloxy)-8-(3''-methylbut-2″-enyloxy)psoralen (3), (2'R)-(+)-5-(2',3'-epoxy-3'-methylbutoxy)-8-(3″-methylbut-2″-enyloxy)psoralen (4), and 5-methoxy-8-((Z)-4'-(3″-methylbutanoate)-3'-methylbut-2'-enyloxy)psoralen (5), along with 15 known compounds (6-20), were isolated from the roots of Angelica dahurica. The structures of the new compounds were elucidated by spectroscopic analysis, along with electronic circular dichroism calculations and Mosher ester analysis. Compounds 3, 4, 11, 13, and 16 reduced H2O2-induced cell death in HepG2 cells and attenuated reactive oxygen species (ROS) formation without showing cytotoxicity, suggesting that these compounds might have cytoprotective effects against H2O2-induced oxidative damage via ROS scavenging activities.
- Published
- 2019
22. Pyranoflavanones and Pyranochalcones from the Fruits of Amomum tsao-ko
- Author
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Dongho Lee, Hye Ryoung Hong, Jun Gu Kim, Hari Jang, Mi Kyeong Lee, Thi Phuong Linh Le, Bang Yeon Hwang, and Jin Tae Hong
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Pharmacology ,biology ,010405 organic chemistry ,Organic Chemistry ,Pharmaceutical Science ,Amomum tsao-ko ,biology.organism_classification ,01 natural sciences ,Amomum ,0104 chemical sciences ,Analytical Chemistry ,Nitric oxide ,010404 medicinal & biomolecular chemistry ,chemistry.chemical_compound ,Complementary and alternative medicine ,chemistry ,Drug Discovery ,Ic50 values ,Molecular Medicine ,Two-dimensional nuclear magnetic resonance spectroscopy ,RAW 264.7 Cells ,Nuclear chemistry - Abstract
Eight new geranylated and farnesylated pyranoflavanones (1-8) and two new farnesylated pyranochalcones (9 and 10) were isolated from the methanolic extract of the fruits of Amomum tsao-ko. Their structures were elucidated by extensive analysis of the 1D and 2D NMR spectra and from the HRESIMS, combined with experimental ECD data. All compounds were evaluated for their inhibitory effects on the nitric oxide production against lipopolysaccharide-induced RAW 264.7 macrophages and exhibited IC50 values ranging from 10.6 to 41.5 μM.
- Published
- 2019
23. Bioactive Diterpenoids from the Stems of Euphorbia royleana
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Yasushi Ohizumi, Chenyue Zhang, Yuanqiang Guo, Peixia Wang, Jing Xu, Chunfeng Xie, Shuo Yuan, Muhetaer Tuerhong, Lijun An, Jie Zhang, Da Qing Jin, Dongho Lee, Xueyuan Yang, and Yaru Xi
- Subjects
Pharmacology ,Magnetic Resonance Spectroscopy ,Plant Stems ,biology ,Plant Extracts ,Stereochemistry ,Chemistry ,Organic Chemistry ,Pharmaceutical Science ,Nitric Oxide ,biology.organism_classification ,Terpenoid ,Analytical Chemistry ,Euphorbia royleana ,Molecular Docking Simulation ,Complementary and alternative medicine ,Euphorbia ,Drug Discovery ,Ic50 values ,Molecular Medicine ,Diterpenes - Abstract
Two ingenane- (1 and 2), two ent-atisane- (3 and 4), two ent-kaurane- (5 and 6), two ent-abietane- (7 and 8), and one ent-isopimarane-type (9) diterpenoid and 12 known analogues have been isolated from the methanolic extract of the stems of Euphorbia royleana. Their structures, including absolute configurations, were determined by extensive spectroscopic methods and ECD data analysis. The nitric oxide inhibitory activities of those diterpenoids were examined biologically in lipopolysaccharide-stimulated BV-2 cells, with compounds 1, 2, 5–7, 10, and 12 having IC50 values lower than 40 μM. Molecular docking was used to investigated the possible mechanism of compounds 1, 2, 5–7, 10, and 12.
- Published
- 2019
24. Electrochemical Oxidation of Metal–Catechol Complexes as a New Synthesis Route to the High-Quality Ternary Photoelectrodes: A Case Study of Fe2TiO5 Photoanodes
- Author
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Valentin Urena Baltazar, Dongho Lee, Tyler J. Smart, Kyoung-Shin Choi, and Yuan Ping
- Subjects
021110 strategic, defence & security studies ,Working electrode ,Materials science ,Metal ions in aqueous solution ,0211 other engineering and technologies ,Oxide ,02 engineering and technology ,Photoelectrochemical cell ,021001 nanoscience & nanotechnology ,Polaron ,Electrochemistry ,Metal ,chemistry.chemical_compound ,Chemical engineering ,chemistry ,visual_art ,Electrode ,visual_art.visual_art_medium ,General Materials Science ,0210 nano-technology - Abstract
A new electrochemical, solution-based synthesis method to prepare uniform multinary oxide photoelectrodes was developed. This method involves solubilizing multiple metal ions as metal-catechol complexes in a pH condition where they are otherwise insoluble. When some of the catechol ligands are electrochemically oxidized, the remaining metal complexes become insoluble and are deposited as metal-catechol films on the working electrode. The resulting films are then annealed to form crystalline multinary oxide electrodes. Because catechol can serve as a complexing agent for a variety of metal ions, the newly developed method can be used to prepare a variety of multinary oxide films. In the present study, we used this method to prepare n-type Fe2TiO5 photoanodes and investigated their photoelectrochemical properties for use in a photoelectrochemical water-splitting cell. We also performed a computational investigation with two goals. The first goal was to investigate small electron polaron formation in Fe2TiO5. Charge transport in most oxide photoelectrodes involves small polaron hopping, but small polaron formation in Fe2TiO5 has not been examined prior to this work. The second goal was to investigate the effect of substitutional Sn doping at the Fe site on the electronic band structure and the carrier concentration of Fe2TiO5. The combined experimental and theoretical results presented in this study greatly improve our understanding of Fe2TiO5 for use as a photoanode.
- Published
- 2020
25. Enabling Solar Water Oxidation by BiVO4 Photoanodes in Basic Media
- Author
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Dongho Lee, Alexander Kvit, and Kyoung-Shin Choi
- Subjects
Materials science ,General Chemical Engineering ,02 engineering and technology ,General Chemistry ,010402 general chemistry ,021001 nanoscience & nanotechnology ,Electrochemistry ,01 natural sciences ,0104 chemical sciences ,chemistry.chemical_compound ,Atomic layer deposition ,Sulfite ,chemistry ,Chemical engineering ,Titanium dioxide ,Electrode ,Materials Chemistry ,Deposition (phase transition) ,Chemical stability ,0210 nano-technology ,Layer (electronics) - Abstract
Titanium dioxide (TiO2) deposited by atomic layer deposition (ALD) has been the most commonly used protection layer to enhance chemical and photoelectrochemical stabilities of photoelectrodes. In this study, we report a new electrochemical deposition method that can place a thin, conformal TiO2 coating layer on a photoelectrode. This method takes
- Published
- 2018
26. Microscopic Analysis of Inherent Void Passivation in Perovskite Solar Cells
- Author
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Tae Kyu Ahn, Jucheol Park, Jooho Lee, Ki-Hong Kim, Dongho Lee, Yonghui Lee, Jaehan Lee, Minsu Seol, Gabseok Seo, Dongwook Lee, Dong Wook Kwak, Seong Heon Kim, Mohammad Khaja Nazeeruddin, Sung Heo, Hoon Young Cho, and Dongwha Lee
- Subjects
Void (astronomy) ,Materials science ,Passivation ,Band gap ,Energy Engineering and Power Technology ,Astrophysics::Cosmology and Extragalactic Astrophysics ,02 engineering and technology ,Electron ,urologic and male genital diseases ,010402 general chemistry ,01 natural sciences ,law.invention ,Condensed Matter::Materials Science ,Optics ,law ,Electric field ,Solar cell ,Materials Chemistry ,Renewable Energy, Sustainability and the Environment ,business.industry ,021001 nanoscience & nanotechnology ,female genital diseases and pregnancy complications ,0104 chemical sciences ,Fuel Technology ,Band bending ,Chemistry (miscellaneous) ,Optoelectronics ,0210 nano-technology ,business ,Recombination - Abstract
The presence of voids in perovskite solar cells influences the efficiency because of accelerated charge recombination. The induced electric field near voids due to band bending attracts photogenerated electrons and holes toward the voids, leading to carrier recombination. However, if the surface of the voids is coated by materials with a band gap higher than that of the perovskite layer, the strong electric field induced near the voids in the opposite way prevents carriers from recombining. We identified voids in the perovskite layer by using an electron beam-induced current technique and found the influence of field-assisted passivation by organic materials on the efficiency of the solar cell.
- Published
- 2017
27. Antiviral Activities of Trichothecenes Isolated from Trichoderma albolutescens against Pepper Mottle Virus
- Author
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Ki Hyun Ryu, Beom Seok Kim, Eun Gyeong Song, Seung Mok Ryu, Dongho Lee, Hae Min Lee, Jun Lee, Jin Sung Hong, Young Hye Seo, Jae Jin Kim, and Yuanqiang Guo
- Subjects
0301 basic medicine ,Potyvirus ,Trichodermin ,Trichothecene ,Nicotiana benthamiana ,Biology ,010402 general chemistry ,Antiviral Agents ,01 natural sciences ,Green fluorescent protein ,Pepper mottle virus ,03 medical and health sciences ,chemistry.chemical_compound ,Tobacco ,Pepper ,Plant Diseases ,Trichoderma ,Host (biology) ,fungi ,food and beverages ,General Chemistry ,biology.organism_classification ,Virology ,0104 chemical sciences ,030104 developmental biology ,chemistry ,Biochemistry ,Vibrational circular dichroism ,Trichothecenes ,General Agricultural and Biological Sciences - Abstract
A bioassay-guided isolation using a green fluorescence protein (GFP)-tagged pepper mottle virus (PepMoV-GFP) based leaf-disk method to obtain new antiviral agents led to the isolation of trichodermin, 1, and a new compound trichoderminol, 2, from EtOAc extract of Trichoderma albolutescens culture medium. The structures of compounds 1 and 2 were determined by MS and NMR experiments, and the absolute configurations of the compounds were established by experimental and calculated vibrational circular dichroism spectra. Compounds 1 and 2 were evaluated for their anti-PepMoV potential in systemic host plants, such as tobacco and pepper, by PepMoV-GFP based systemic host method. All compounds exhibited inactivation effects against PepMoV. Furthermore, compound 1 showed protective effects against PepMoV.
- Published
- 2017
28. Methods for Electrochemical Synthesis and Photoelectrochemical Characterization for Photoelectrodes
- Author
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Kyoung-Shin Choi, Gokul V. Govindaraju, Garrett P. Wheeler, and Dongho Lee
- Subjects
Materials science ,business.industry ,General Chemical Engineering ,Nanotechnology ,02 engineering and technology ,General Chemistry ,Semiconductor electrode ,010402 general chemistry ,021001 nanoscience & nanotechnology ,Electrochemistry ,Solar fuel ,01 natural sciences ,0104 chemical sciences ,Characterization (materials science) ,Semiconductor ,Plating ,Electrode ,Materials Chemistry ,0210 nano-technology ,business - Abstract
Electrodeposition is a widely used technique for electrode synthesis in various applications. Because of its low synthesis cost and easy scalability, electrodeposition is particularly attractive for the production of semiconductor and catalyst electrodes for use in solar fuel production. For researchers who are interested in learning about or utilizing electrodeposition, the current paper describes detailed methods for electrodeposition, which include procedures for preparing electrodes and plating solutions, determining deposition conditions, and performing electrodeposition. Postdeposition treatments that can be used to prepare electrodes of more diverse compositions and photodeposition procedures that can be used to place catalyst layers on semiconductor electrodes are also provided. The methods are described using the synthesis and modification of photoelectrodes as an example, but most principles and procedures explained in this paper are general and can be applied to electrodeposition of various ele...
- Published
- 2016
29. Sesquiterpenes from Inula japonica with Inhibitory Effects on Nitric Oxide Production in Murine Macrophage RAW 264.7 Cells
- Author
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Youngsoo Kim, Hari Jang, Jieun Choi, Dongho Lee, Bang Yeon Hwang, Qinghao Jin, Mi Kyeong Lee, Jin Tae Hong, and Jin Woo Lee
- Subjects
Lipopolysaccharides ,Inula japonica ,Pharmaceutical Science ,Flowers ,Nitric Oxide ,Bioinformatics ,Inhibitory postsynaptic potential ,01 natural sciences ,Non steroidal ,Analytical Chemistry ,Nitric oxide ,Inhibitory Concentration 50 ,Lactones ,Mice ,chemistry.chemical_compound ,Republic of Korea ,Drug Discovery ,Ic50 values ,Animals ,Macrophage ,Nuclear Magnetic Resonance, Biomolecular ,RAW 264.7 Cells ,Pharmacology ,Molecular Structure ,010405 organic chemistry ,Chemistry ,Macrophages ,Anti-Inflammatory Agents, Non-Steroidal ,Organic Chemistry ,Plant Components, Aerial ,0104 chemical sciences ,010404 medicinal & biomolecular chemistry ,Complementary and alternative medicine ,Biochemistry ,Molecular Medicine ,Inula ,Sesquiterpenes ,Two-dimensional nuclear magnetic resonance spectroscopy - Abstract
Eight new sesquiterpenes (1-8), along with seven known sesquiterpenes (9-15), were isolated from a methanol extract of the flowers of Inula japonica. Their structures were elucidated by a combination of 1D and 2D NMR spectroscopic and HRESIMS data. All of isolates were evaluated for their inhibitory effects on nitric oxide production in LPS-induced RAW 264.7 cells, with their IC50 values ranging from 1.9 to 15.4 μM.
- Published
- 2016
30. Di- and Triterpenoids from the Leaves of Casearia balansae and Neurite Outgrowth Promoting Effects of PC12 Cells
- Author
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Xiangrong Cao, Yasushi Ohizumi, Kasimu Rena, Jing Xu, Dongho Lee, Jing Kang, Xiaocong Sun, Quanhui Ren, Shen Li, and Yuanqiang Guo
- Subjects
Neurite ,Casearia ,Stereochemistry ,Pharmaceutical Science ,PC12 Cells ,01 natural sciences ,Diterpenes, Clerodane ,Analytical Chemistry ,Terpene ,Triterpenoid ,Drug Discovery ,Neurites ,Animals ,Organic chemistry ,Nuclear Magnetic Resonance, Biomolecular ,Pharmacology ,Molecular Structure ,biology ,010405 organic chemistry ,Organic Chemistry ,Circular dichroism spectra ,biology.organism_classification ,Triterpenes ,Terpenoid ,Rats ,0104 chemical sciences ,Plant Leaves ,010404 medicinal & biomolecular chemistry ,Complementary and alternative medicine ,Phytochemical ,Molecular Medicine ,Drugs, Chinese Herbal - Abstract
A bioassay-guided phytochemical investigation of the leaves of Casearia balansae led to the isolation of six new cucurbitane-type triterpenoid derivatives (balanterpenes A-F, 1-6) and four new clerdoane-type diterpenoids (balanterpenes G-J, 7-10). The structures of 1-10 were established on the basis of extensive analysis of NMR spectroscopic data, X-ray crystallography, and experimental and calculated electronic circular dichroism spectra. Compound 1 features a ring-expanded triterpenoid skeleton with the C-19 methyl involved in the ring formation, compound 6 possesses a rare hexanortriterpenoid scaffold, and compounds 7-10 may be four new diterpenoid artifacts presumably formed during the extraction and purification processes. Compounds 3 and 7-10 showed promoting effects on neurite outgrowth of PC12 cells with EC50 values in the range 2.9-10.0 μM.
- Published
- 2015
31. 2-Phenoxychromones and Prenylflavonoids from Epimedium koreanum and Their Inhibitory Effects on LPS-Induced Nitric Oxide and Interleukin-1β Production
- Author
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Qinghao Jin, Mi Kyeong Lee, Dongho Lee, Jin Tae Hong, Eung Tae Yeon, Youngsoo Kim, Bang Yeon Hwang, Jin Woo Lee, Chul Lee, and Sang-Bae Han
- Subjects
Lipopolysaccharides ,Epimedium koreanum ,Interleukin-1beta ,Nitric oxide biosynthesis ,Nitric Oxide Synthase Type II ,Pharmaceutical Science ,Nitric Oxide ,Inhibitory postsynaptic potential ,Analytical Chemistry ,Nitric oxide ,Inhibitory Concentration 50 ,Mice ,chemistry.chemical_compound ,Drug Discovery ,Ic50 values ,Animals ,Inhibitory concentration 50 ,Nuclear Magnetic Resonance, Biomolecular ,Epimedium ,Flavonoids ,Pharmacology ,Chromatography ,Molecular Structure ,Macrophages ,Organic Chemistry ,Interleukin 1β ,Complementary and alternative medicine ,chemistry ,Chromones ,Molecular Medicine ,Methanol - Abstract
Two new 2-phenoxychromones 1 and 2 and two prenylflavonoids 3 and 4 along with 12 known compounds (5-16) were isolated from the CH2Cl2-soluble fraction of a methanol extract of Epimedium koreanum. Compounds 1, 4, 6, 7, 9, 10, 12, and 15 exhibit inhibitory effects on nitric oxide production with IC50 values ranging from 16.8 to 49.3 μM. Compounds 1, 4, 7, and 12 also showed inhibitory effects on interleukin-1β production with IC50 values ranging from 8.6 to 38.9 μM in RAW 264.7 macrophages.
- Published
- 2014
32. Nontargeted Metabolomics Approach for Age Differentiation and Structure Interpretation of Age-Dependent Key Constituents in Hairy Roots of Panax ginseng
- Author
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Seon-Woo Cha, DongHyuk Lee, Hyung-Kyoon Choi, Kyong-Hwan Bang, Dongho Lee, Kemok Kim, Yoo-Soo Shin, Bang Yeon Hwang, Jae Won Lee, and Nahyun Kim
- Subjects
Ginsenosides ,Metabolite ,Panax ,Pharmaceutical Science ,Age dependent ,Tandem mass spectrometry ,Mass spectrometry ,Plant Roots ,Mass Spectrometry ,Analytical Chemistry ,chemistry.chemical_compound ,Ginseng ,Metabolomics ,Republic of Korea ,Drug Discovery ,Pharmacology ,Chromatography ,Molecular Structure ,Organic Chemistry ,food and beverages ,Complementary and alternative medicine ,chemistry ,Ginsenoside ,Molecular Medicine ,Classification methods ,Chromatography, Liquid - Abstract
The age of the ginseng plant has been considered as an important criterion to determine the quality of this species. For age differentiation and structure interpretation of age-dependent key constituents of Panax ginseng, hairy root (fine root) extracts aged from four to six years were analyzed using a nontargeted approach with ultraperformance liquid chromatography/quadrupole time-of-flight mass spectrometry (UPLC-QTOFMS). Various classification methods were used to determine an optimal method to best describe ginseng age by selecting influential metabolites of different ages. Through the metabolite selection process, several age-dependent key constituents having the potential to be biomarkers were determined, and their structures were identified according to tandem mass spectrometry and accurate mass spectrometry by comparing them with an in-house ginsenoside library and with literature data. This proposed method applied to the hairy roots of P. ginseng showed an improved efficiency of age differentiation when compared to previous results on the main roots and increases the possibility of the identification of key metabolites that can be used as biomarker candidates for quality assurance in ginseng.
- Published
- 2012
33. Antiulcer Activity of Anthocyanins from Rubus coreanus via Association with Regulation of the Activity of Matrix Metalloproteinase-2
- Author
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Sung Joon Lee, Sang-Ho Yoo, Hyunju Lee, Sun Joong Kim, Dongho Lee, Hyo Ihl Chang, and Bum-Soo Kim
- Subjects
Male ,Antioxidant ,medicine.medical_treatment ,Rubus coreanus ,Pharmacology ,Antioxidants ,Gene Expression Regulation, Enzymologic ,Anthocyanins ,Rats, Sprague-Dawley ,Superoxide dismutase ,Lipid peroxidation ,chemistry.chemical_compound ,Cell Line, Tumor ,medicine ,Animals ,Humans ,Zymography ,Stomach Ulcer ,Rosaceae ,chemistry.chemical_classification ,Reactive oxygen species ,biology ,Plant Extracts ,Chemistry ,Glutathione peroxidase ,food and beverages ,General Chemistry ,biology.organism_classification ,Rats ,Disease Models, Animal ,Oxidative Stress ,Biochemistry ,Catalase ,biology.protein ,Matrix Metalloproteinase 2 ,Lipid Peroxidation ,General Agricultural and Biological Sciences - Abstract
Anthocyanins were extracted from the fruits of Rubus coreanus. Whether their antioxidant properties and antiulcer activity in gastric ulceration have been accompanied by the activation of matrix metalloproteainse-2 (MMP-2) was investigated. To assess the effect of anthocyanins on gastric ulcer, the rats were administered with anthocyanins (20, 50, and 80 mg/kg of body weight) before treatment with naproxen (80 mg/kg of body weight) to induce gastric ulceration. Lipid peroxidation and the activities of radical scavenging enzymes such as catalase, superoxide dismutase, and glutathione peroxidase were determined. The MMP-2 level was tested by zymography and Western blot. Anthocyanins of R. coreanus exhibit possible antiulcer activity in acute ulcer in a rat model by preventing lipid peroxidation and a significant increase in the activities of antioxidant enzymes such as catalase, superoxide dismutase, and glutathione peroxidase. Also, anthocyanins induce activation of MMP-2 and attenuate the activity of the proinflammatory molecules, such as tumor necrosis factor-α and interleukin-1β.
- Published
- 2011
34. Metabolomic Approach for Age Discrimination of Panax ginseng Using UPLC-Q-Tof MS
- Author
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Hyung-Kyoon Choi, Jae Won Lee, DongHyuk Lee, Yoo-Soo Shin, Dongho Lee, Kyong-Hwan Bang, Seon-Woo Cha, Kemok Kim, Byeong Yeob Choi, Nahyun Kim, and Dae Sik Jang
- Subjects
Time Factors ,Chromatography ,Multivariate analysis ,Plant Extracts ,Metabolite ,Panax ,General Chemistry ,Biology ,Mass Spectrometry ,Uplc q tof ms ,Age discrimination ,Hierarchical clustering ,chemistry.chemical_compound ,Ginseng ,Metabolomics ,chemistry ,Multivariate Analysis ,Principal component analysis ,General Agricultural and Biological Sciences ,Chromatography, High Pressure Liquid - Abstract
An ultraperformance liquid chromatography-quadrupole time-of-flight mass spectrometry (UPLC-Q-Tof MS)-based metabolomic technique was applied for metabolite profiling of 60 Panax ginseng samples aged from 1 to 6 years. Multivariate statistical methods such as principal component analysis and hierarchical clustering analysis were used to compare the derived patterns among the samples. The data set was subsequently applied to various metabolite selection methods for sophisticated classification with the optimal number of metabolites. The results showed variations in accuracy among the classification methods for the samples of different ages, especially for those aged 4, 5, and 6 years. This proposed analytical method coupled with multivariate analysis is fast, accurate, and reliable for discriminating the cultivation ages of P. ginseng samples and is a potential tool to standardize quality control in the P. ginseng industry.
- Published
- 2011
35. Cytotoxic and Antineoplastic Activity of Timosaponin A-III for Human Colon Cancer Cells
- Author
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Sang Kook Lee, Dongho Lee, Hwa Jin Chung, Hyen Joo Park, Eun Kyoung Seo, Yeong Shik Kim, Joo Won Nam, and You Jin Kang
- Subjects
Cyclin A ,Mice, Nude ,Pharmaceutical Science ,Apoptosis ,Biology ,Analytical Chemistry ,Mice ,Drug Discovery ,Animals ,Humans ,Cytotoxic T cell ,Cyclin B1 ,Pharmacology ,Anemarrhena ,Dose-Response Relationship, Drug ,Molecular Structure ,Kinase ,Cell Cycle ,Cyclin-Dependent Kinase 2 ,Organic Chemistry ,Saponins ,Antineoplastic Agents, Phytogenic ,Xenograft Model Antitumor Assays ,Proliferating cell nuclear antigen ,Complementary and alternative medicine ,Cell culture ,Colonic Neoplasms ,Immunology ,Cancer cell ,Cancer research ,biology.protein ,Molecular Medicine ,Steroids ,Poly(ADP-ribose) Polymerases ,Rhizome - Abstract
The potential antitumor activity of timosaponin A-III (1), a steroidal saponin from the rhizomes of Anemarrhena asphodeloides, was investigated in human colorectal cancer HCT-15 cells both in cell culture and in an in vivo murine xenograft model. Compound 1 inhibited the proliferation of cancer cells with cell-cycle arrest and induction of apoptosis. Cell-cycle arrest in the G0/G1 and G2/M phase by 1 was correlated with the down-regulation of cyclin A, cyclin B1, cyclin-dependent kinase 2 (CDK2), CDK4, proliferating cell nuclear antigen, and c-Myc. The increase of the sub-G1 peak by 1 was also closely related to the induction of apoptosis, which was evidenced by the induction of DNA fragmentation, activation of caspases, induction of cleaved poly-(ADP ribose) polymerase, and suppression of Bcl-xL and Bcl-2 expression. In an in vivo xenograft model, treatment with 1 (2 or 5 mg/kg body weight, three times/week, ip administration) for four weeks significantly suppressed tumor growth in athymic nude mice bearing HCT-15 cells, without any overt toxicity. Cell-cycle arrest and induction of apoptosis might be plausible mechanisms of actions for the observed antineoplastic activity of 1.
- Published
- 2011
36. Protuboxepins A and B and Protubonines A and B from the Marine-Derived Fungus Aspergillus sp. SF-5044
- Author
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Yukihiro Asami, Jae-Hyuk Jang, Dongho Lee, Hyuncheol Oh, Jong Seog Ahn, and Sang Un Lee
- Subjects
Stereochemistry ,Pharmaceutical Science ,Antineoplastic Agents ,Marine Biology ,Diketopiperazines ,Fungus ,Analytical Chemistry ,Alkaloids ,Drug Discovery ,Humans ,Nuclear Magnetic Resonance, Biomolecular ,Pharmacology ,chemistry.chemical_classification ,Aspergillus ,Molecular Structure ,biology ,Alkaloid ,Organic Chemistry ,Absolute configuration ,Biological activity ,Fungi imperfecti ,biology.organism_classification ,In vitro ,Complementary and alternative medicine ,chemistry ,Biochemistry ,Oxepins ,Molecular Medicine ,Female ,Lactone - Abstract
Two new oxepin-containing (1 and 2) and two diketopiperazine-type alkaloids (3 and 4) have been isolated from an EtOAc extract of the marine-derived fungus Aspergillus sp. SF-5044. The structures of these metabolites were determined through analysis of NMR and MS data, along with Marfey's method. Compound 1 showed weak growth inhibitory activity against a small panel of cell lines.
- Published
- 2011
37. Identification of Antiadipogenic Constituents of the Rhizomes of Anemarrhena asphodeloides
- Author
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Jun Lee, Sam Sik Kang, Joo Won Nam, Ye Seul Lee, Hana Jeong, Yoojin Lee, Dongho Lee, Jeong-Oon Lee, Eun-Kyoung Seo, Eun Sook Hwang, and Ui Joung Youn
- Subjects
Stereochemistry ,Chemical structure ,Ethyl acetate ,Pharmaceutical Science ,Pharmacognosy ,Analytical Chemistry ,Mice ,chemistry.chemical_compound ,Anemarrhena asphodeloides ,Phenols ,Coumarins ,3T3-L1 Cells ,Drug Discovery ,Animals ,Medicinal plants ,Nuclear Magnetic Resonance, Biomolecular ,Pharmacology ,Anemarrhena ,Adipogenesis ,Korea ,Plants, Medicinal ,Molecular Structure ,biology ,Traditional medicine ,Liliaceae ,Organic Chemistry ,biology.organism_classification ,Rhizome ,Complementary and alternative medicine ,chemistry ,Molecular Medicine - Abstract
Three new phenolic compounds, (E)-4'-demethyl-6-methyleucomin (1), anemarcoumarin A (2), and anemarchalconyn (3), were isolated from an ethyl acetate extract of the rhizomes of Anemarrhena asphodeloides, together with seven known compounds (4-10). The structures of the new compounds (1-3) were determined on the basis of spectroscopic data interpretation. Compound 3 exhibited a potent inhibitory effect against the differentiation of preadipocyte 3T3-L1 cells with an IC50 value of 5.3 microM.
- Published
- 2009
38. Ensemble-Trained PM2.5 Source Apportionment Approach for Health Studies
- Author
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Sangil Lee, Jorge E. Pachon, Dongho Lee, Roshini Shankaran, James A. Mulholland, Sivaraman Balachandran, and Armistead G. Russell
- Subjects
Chemical transport model ,Cosmic microwave background ,Environmental engineering ,Air pollution ,General Chemistry ,Particulates ,Seasonality ,medicine.disease_cause ,medicine.disease ,Atmospheric sciences ,Aerosol ,Models, Chemical ,Health ,Apportionment ,medicine ,Environmental Chemistry ,Environmental science ,Particulate Matter ,Seasons ,Particle Size ,Air quality index - Abstract
An ensemble-trained chemical mass balance (CMB) approach is developed for particulate matter (PM) source apportionment (SA), particularly for use in health studies. The approach uses results from a short-term emission-based chemical transport model (CTM) and multiple receptor-based approaches. Ensemble results have less day-to-day variation in source impacts and fewer biases between observed and estimated PM2.5 mass compared to the original receptor model results. Ensemble results show increases in road dust, biomass burning, and coal impacts, but secondary organic carbon (SOC) impacts decrease. These results, along with observations, are then used to obtain new source profiles. Two sets of new source profiles based on ensemble results in summer (July 2001 and winter (January 2002) were developed, and used in separate CMB applications for a 12-month data set of daily PM2.5 measurements at the Atlanta, GA, Jefferson Street site. Results show that ensemble-trained CMB approaches, using both summer profiles and winter profiles, effectively reduce day-to-day variability of source impact estimates by reducing fewer days of zero impact from sources known to be present as compared to traditional receptor modeling, suggesting improved results.
- Published
- 2009
39. ent-Kaurane Diterpenoids from Isodon japonicus
- Author
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Youngsoo Kim, Dongho Lee, Seon A Lee, Chul Lee, Jin Tae Hong, Ji Sang Hwang, Bang Yeon Hwang, Seong Su Hong, Heesoon Lee, and Xiang Hua Han
- Subjects
Lipopolysaccharides ,Stereochemistry ,Pharmaceutical Science ,Pharmacognosy ,Nitric Oxide ,Analytical Chemistry ,Mice ,chemistry.chemical_compound ,Drug Discovery ,Animals ,Nuclear Magnetic Resonance, Biomolecular ,Ent kaurane ,Pharmacology ,chemistry.chemical_classification ,Lasiokaurin ,Korea ,Plants, Medicinal ,Molecular Structure ,Macrophages ,Organic Chemistry ,Isodon japonicus ,Terpenoid ,Complementary and alternative medicine ,chemistry ,Isodon ,Molecular Medicine ,Hemiacetal ,Diterpene ,Diterpenes, Kaurane ,Lactone - Abstract
Five ent-kaurane diterpenoids, 6beta,7beta,14beta-trihydroxy-1alpha,19-diacetoxy-7alpha,20-epoxy- ent-kaur-16-en-15-one (1), 1alpha,6beta,7beta-trihydroxy-11alpha,19-diacetoxy-7alpha,20-epoxy-ent-kaur-16-en-15-one (2), 6-hydroxy-1alpha,19-diacetoxy-6,7-seco-ent-kaur-16-en-15-one-7,20-olide (3), 19-hydroxy-1alpha,6-diacetoxy-6,7-seco- ent-kaur-16-en-15-one-7,20-olide (4), and 6-aldehyde-1alpha,19-diacetoxy-6,7-seco- ent-kaur-16-en-15-one-7,20-olide (5), along with 10 known ent-kaurane diterpenoids, pseurata C (6), longikaurin C (7), effusanin C (8), longikaurin B (9), longikaurin D (10), effusanin D (11), excisanin B (12), lasiokaurin (13), megathyrin A (14), and loxothyrin A (15), were isolated from the aerial parts of Isodon japonicus. Their structures were determined on the basis of spectroscopic (1D-, 2D-NMR and MS) and chemical evidence. The isolates were evaluated for their inhibitory effects on LPS-induced production of nitric oxide in murine macrophage RAW264.7 cells.
- Published
- 2008
40. Abietane Diterpenes from Salvia miltiorrhiza Inhibit the Activation of Hypoxia-Inducible Factor-1
- Author
-
Jung Joon Lee, Xuejun Jin, Dongho Lee, Kyeong Lee, Jeong-Hyung Lee, Young-Soo Hong, Youngho Kim, and Nguyen Tien Dat
- Subjects
Stereochemistry ,Pharmaceutical Science ,Salvia miltiorrhiza ,Biology ,Analytical Chemistry ,chemistry.chemical_compound ,Drug Discovery ,Gene expression ,Tumor Cells, Cultured ,Humans ,Luciferase ,Abietane ,Pharmacology ,Reporter gene ,Korea ,Plants, Medicinal ,Dose-Response Relationship, Drug ,Organic Chemistry ,Biological activity ,Antineoplastic Agents, Phytogenic ,Molecular biology ,Vascular endothelial growth factor ,Complementary and alternative medicine ,chemistry ,Cell culture ,Abietanes ,Molecular Medicine ,Hypoxia-Inducible Factor 1 - Abstract
The hypoxia-inducible factor-1 (HIF-1) has been known to be correlated to the adaptation and proliferation of tumor cells; therefore HIF-1 has become an important target in the development of anticancer drugs. A phytochemical study of the CHCl3-soluble fraction of Salvia miltiorrhiza, which strongly inhibited hypoxia-induced reporter gene expression, led to the isolation of 12 abietane-type diterpenes. Of these compounds, sibiriquinone A (1), sibiriquinone B (2), cryptotanshinone (3), and dihydrotanshinone I (4) potently inhibited hypoxia-induced luciferase expression with IC50 values of 0.34, 3.36, 1.58, and 2.05 microM on AGS cells, a human gastric cancer cell line, and 0.28, 3.18, 1.36, and 2.29 microM on Hep3B cells, a human hepatocarcinoma cell line, respectively. Consistently, 1 and 4 dose-dependently suppressed the HIF-1alpha accumulation and 1 inhibited mRNA expression of vascular endothelial growth factor (VEGF) under hypoxia. These results suggest that the anticancer activity of tanshinones is likely at least in part associated with their inhibition of HIF-1 accumulation.
- Published
- 2007
41. Alvaradoins E−N, Antitumor and Cytotoxic Anthracenone C-Glycosides from the Leaves of Alvaradoa haitiensis
- Author
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Craig R. Fairchild, Robert A. Izydore, Nam Cheol Kim, Ricardo Garcia, Dongho Lee, Francisco Jiménez, Hernán A. Navarro, Tyler N. Graf, Eun-Kyoung Seo, Djaja D. Soejarto, Norman R. Farnsworth, Robert Wild, William C. Rose, Mansukh C. Wani, David J. Kroll, Sharnelle S. Phifer, Nicholas H. Oberlies, A. Douglas Kinghorn, and Monroe E. Wall
- Subjects
Pharmaceutical Science ,Pharmacognosy ,Pharmacology ,Biology ,Models, Biological ,KB Cells ,Article ,Analytical Chemistry ,Structure-Activity Relationship ,In vivo ,Drug Discovery ,Animals ,Humans ,Structure–activity relationship ,Cytotoxic T cell ,Cytotoxicity ,Anthracenes ,Plants, Medicinal ,Molecular Structure ,Leukemia P388 ,Dominican Republic ,Monosaccharides ,Organic Chemistry ,Antineoplastic Agents, Phytogenic ,In vitro ,Plant Leaves ,Complementary and alternative medicine ,Epidermoid carcinoma ,Biochemistry ,Cell culture ,Simaroubaceae ,Molecular Medicine ,Drug Screening Assays, Antitumor - Abstract
Bioactivity-directed fractionation of an extract of the leaves of Alvaradoa haitiensis, using the KB (human oral epidermoid carcinoma) cell line, led to the isolation and identification of 10 new anthracenone C-glycosides, alvaradoins E-N (1-10), along with the known compound chrysophanol (11). The cytotoxicity of all compounds was evaluated, and preliminary structure-activity relationships are suggested. The most potent compounds in the in vitro assays (1 and 2) were evaluated in vivo versus the P388 (murine lymphocytic leukemia) model, and alvaradoin E (1) showed antileukemic activity (125% T/C) at a dose of 0.2 mg kg-1 per injection when administered intraperitoneally.
- Published
- 2007
42. Kaurane Diterpenoids from Isodon excisus Inhibit LPS-Induced NF-κB Activation and NO Production in Macrophage RAW264.7 Cells
- Author
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Seon A Lee, Dongho Lee, Jai Seup Ro, Seong Su Hong, Xiang Hua Han, Jeong Hyung Lee, Bang Yeon Hwang, Jin Tae Hong, Jung Joon Lee, Youngsoo Kim, and Hui Zi Jin
- Subjects
Pharmacology ,Organic Chemistry ,Pharmaceutical Science ,Biological activity ,Biology ,Pharmacognosy ,Terpenoid ,In vitro ,Analytical Chemistry ,Nitric oxide ,chemistry.chemical_compound ,Complementary and alternative medicine ,Biochemistry ,chemistry ,Cell culture ,Drug Discovery ,Molecular Medicine ,Macrophage ,Diterpene - Abstract
As part of an ongoing search for plant-derived compounds that inhibit the activation of NF-kappaB, the methanol extract of the aerial parts of Isodon excisus was found to have significant inhibitory effects on the activation of NF-kappaB in murine macrophage RAW264.7 cells. Bioactivity-guided isolation of the extract yielded five new diterpenoids, excisusin A-E (1-5), along with seven known compounds, inflexarabdonin I (6), inflexarabdonin G (7), inflexin (8), inflexanin A (9), inflexanin B (10), inflexinol (11), and inflexarabdonin A (12). The structures were determined by analysis of the spectroscopic data including 2D NMR. All of the isolates were evaluated for their inhibitory effects on LPS-induced NF-kappaB activation and nitric oxide production in RAW264.7 cells.
- Published
- 2007
43. A Hexacyclic ent-Trachylobane Diterpenoid Possessing an Oxetane Ring from Mitrephora glabra
- Author
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Nicholas H. Oberlies, Norman R. Farnsworth, Achmad M. Saribi, Joseph O. Falkinham, Sharnelle S. Phifer, A. Douglas Kinghorn, Soedarsono Riswan, Djaja D. Soejarto, Yuka Nakanishi, Tyler N. Graf, Chen Li, Fransisca M. Setyowati, Mansukh C. Wani, Dongho Lee, David J. Kroll, and Jason P. Burgess
- Subjects
Ketone ,Stereochemistry ,Annonaceae ,Microbial Sensitivity Tests ,Saccharomyces cerevisiae ,Ring (chemistry) ,Oxetane ,Biochemistry ,Article ,chemistry.chemical_compound ,Amphotericin B ,Tumor Cells, Cultured ,Humans ,Physical and Theoretical Chemistry ,Cytotoxicity ,chemistry.chemical_classification ,Plants, Medicinal ,Bacteria ,Molecular Structure ,biology ,Organic Chemistry ,Mitrephora glabra ,biology.organism_classification ,Antineoplastic Agents, Phytogenic ,Terpenoid ,chemistry ,Diterpenes ,Drug Screening Assays, Antitumor - Abstract
[chemical reaction: see text]. Three new ent-trachylobane diterpenoids (1-3) were isolated and structures elucidated from Mitrephora glabra Scheff. (Annonaceae). Mitrephorone A (1) possesses a hexacyclic ring system with adjacent ketone moieties and an oxetane ring, both of which are unprecedented among trachylobanes. All compounds were evaluated for cytotoxicity against a panel of cancer cells, where 1 displayed the most potent and broadest activity, and against a battery of antimicrobial assays, where all compounds were approximately equipotent.
- Published
- 2005
44. Aromatase Inhibitors from Broussonetia papyrifera
- Author
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Dongho Lee, Krishna P. L. Bhat, Harry H. S. Fong, Norman R. Farnsworth, John M. Pezzuto, and A. Douglas Kinghorn
- Subjects
Magnetic Resonance Spectroscopy ,Spectrophotometry, Infrared ,Placenta ,Flavonoid ,Pharmaceutical Science ,Pharmacognosy ,Moraceae ,Mass Spectrometry ,Analytical Chemistry ,Chalcone ,Chalcones ,Pregnancy ,Drug Discovery ,Enzyme Inhibitors ,Aromatase ,chemistry.chemical_classification ,Molecular Structure ,biology ,Aromatase Inhibitors ,Chemistry ,Circular Dichroism ,Biological activity ,Biochemistry ,Enzyme inhibitor ,Flavanones ,Molecular Medicine ,Female ,Algorithms ,Inhibitory Concentration 50 ,Structure-Activity Relationship ,Microsomes ,medicine ,Anticarcinogenic Agents ,Humans ,Benzofurans ,Flavonoids ,Pharmacology ,Plants, Medicinal ,Terpenes ,Organic Chemistry ,Cancer ,Broussonetia ,medicine.disease ,biology.organism_classification ,Complementary and alternative medicine ,Polyphenol ,biology.protein ,Spectrophotometry, Ultraviolet ,Illinois - Abstract
Bioassay-guided fractionation of an ethyl acetate-soluble extract from the whole plants of Broussonetia papyrifera, using an in vitro aromatase inhibition assay, led to the isolation of five new active compounds, 5,7,2',4'-tetrahydroxy-3-geranylflavone (1), isogemichalcone C (8), 3'-[gamma-hydroxymethyl-(E)-gamma-methylallyl]-2,4,2',4'-tetrahydroxychalcone 11'-O-coumarate (9), demethylmoracin I (10), and (2S)-2',4'-dihydroxy-2' '-(1-hydroxy-1-methylethyl)dihydrofuro[2,3-h]flavanone (11), and 10 known (12-21) compounds which were also found to be active. Of these compounds, the most potent were 9 (IC(50) 0.5 microM), 11 (IC(50) 0.1 microM), isolicoflavonol (12, IC(50) 0.1 microM), and (2S)-abyssinone II (13, IC(50) 0.4 microM). Additionally, six new compounds, 5,7,3',4'-tetrahydroxy-6-geranylflavonol (2), 5,7,3',4'-tetrahydroxy-3-methoxy-6-geranylflavone (3), (2S)-7,4'-dihydroxy-3'-prenylflavan (4), 1-(2,4-dihydroxyphenyl)-3-(4-hydroxyphenyl)propane (5), 1-(2,4-dihydroxy-3-prenylphenyl)-3-(4-hydroxyphenyl)propane (6), and 1-(4-hydroxy-2-methoxyphenyl)-3-(4-hydroxy-3-prenylphenyl)propane (7), were isolated and characterized, but proved to be inactive as aromatase inhibitors, as were an additional 21 known compounds. The structures of the new compounds (1-11) were elucidated by spectroscopic methods. Structure-activity relationships in the aromatase assay were determined for the benzofurans, biphenylpropanoids, coumarins, and various types of flavonoids (chalcones, flavans, flavanones, and flavones) obtained among a total of 42 constituents of B. papyrifera.
- Published
- 2001
45. Effect of a 17α-(3-Hydroxypropyl)-17β-acetyl Substituent Pattern on the Glucocorticoid and Progestin Receptor Binding of 11β-Arylestra-4,9-dien-3-ones
- Author
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Clarence Cook, Dongho Lee, Raje P, and John A. Kepler
- Subjects
medicine.medical_specialty ,medicine.drug_class ,Organic Chemistry ,Substituent ,Biochemistry ,Glucocorticoid receptor binding ,chemistry.chemical_compound ,Glucocorticoid receptor ,Endocrinology ,chemistry ,Internal medicine ,polycyclic compounds ,medicine ,Physical and Theoretical Chemistry ,Progestin ,hormones, hormone substitutes, and hormone antagonists ,Glucocorticoid ,medicine.drug - Abstract
Replacing the 17α-acetoxy substituent in an antiprogestational 17β-acetyl-11β-arylestra-4,9-dien-3-one by 3-hydroxypropyl significantly diminished glucocorticoid receptor binding with little effect on progestin receptor binding.
- Published
- 2001
46. Cytotoxic Flavone Analogues of Vitexicarpin, a Constituent of the Leaves of Vitex negundo
- Author
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Daniel Chávez, Hee Byung Chai, Qiuwen Mi, John M. Pezzuto, Soedarsono Riswan, Dongho Lee, Geoffrey A. Cordell, Fredyc Diaz, Leonardus B.S. Kardono, A. Douglas Kinghorn, Ghee Teng Tan, Craig R. Fairchild, Norman R. Farnsworth, and Robert A. Wild
- Subjects
Male ,Lung Neoplasms ,Vitex negundo ,Stereochemistry ,Acylation ,Flavonoid ,Pharmaceutical Science ,Pharmacology ,Pharmacognosy ,Methylation ,Analytical Chemistry ,Vitex ,Inhibitory Concentration 50 ,Mice ,chemistry.chemical_compound ,In vivo ,Drug Discovery ,LNCaP ,Tumor Cells, Cultured ,Animals ,Humans ,Phenols ,Cytotoxicity ,Nuclear Magnetic Resonance, Biomolecular ,Flavonoids ,chemistry.chemical_classification ,Plants, Medicinal ,Molecular Structure ,biology ,Leukemia P388 ,Chemistry ,Organic Chemistry ,Prostatic Neoplasms ,biology.organism_classification ,Antineoplastic Agents, Phytogenic ,Plant Leaves ,Disease Models, Animal ,Complementary and alternative medicine ,Indonesia ,Colonic Neoplasms ,Molecular Medicine ,Drug Screening Assays, Antitumor - Abstract
Bioassay-guided fractionation of the chloroform-soluble extract of the leaves of Vitex negundo led to the isolation of the known flavone vitexicarpin (1), which exhibited broad cytotoxicity in a human cancer cell line panel. In an attempt to increase the cytotoxic potency of 1, a series of acylation reactions was performed on this compound to obtain its methylated (2), acetylated (3), and six new acylated (4-9) derivatives. Compound 9, the previously unreported 5,3'-dihexanoyloxy-3,6,7,4'-tetramethoxyflavone, showed comparative cytotoxic potency to compound 1 and was selected for further evaluation. However, this compound was found to be inactive when evaluated in the in vivo hollow fiber assay with Lu1, KB, and LNCaP cells at the highest dose (40 mg/kg/body weight) tested, and in the in vivo P-388 leukemia model (135 mg/kg), using the ip administration route.
- Published
- 2003
47. Correction to Polyhydroxylated Macrolides from Seimatosporium discosioides and Their Effects on the Activation of Peroxisome Proliferator-Activated Receptor Gamma
- Author
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Nguyen Tuan Hiep, Yun-hyeok Choi, Nahyun Kim, Seong Su Hong, Seung-Beom Hong, Bang Yeon Hwang, Hak-Ju Lee, Sung-Joon Lee, Dae Sik Jang, and Dongho Lee
- Subjects
Pharmacology ,Complementary and alternative medicine ,Organic Chemistry ,Drug Discovery ,Pharmaceutical Science ,Molecular Medicine ,Analytical Chemistry - Published
- 2012
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