66 results on '"Tian, Ze-an"'
Search Results
2. Diarylheptanoid‐flavanone Hybrids as Multiple‐target Antidiabetic Agents from Alpinia katsumadai
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Yuanqiang Guo, Xiao-Yan Huang, Ji-Jun Chen, Tian-Ze Li, Chang-An Geng, Xue-Mei Zhang, Jing Hu, and Xiao-Feng He
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chemistry.chemical_compound ,chemistry ,biology ,Traditional medicine ,Diarylheptanoid ,Alpinia ,General Chemistry ,biology.organism_classification ,Multiple target ,Flavanone ,Antidiabetic agents - Published
- 2021
3. New guaiane-type sesquiterpenoid dimers from Artemisia atrovirens and their antihepatoma activity
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Xue-Mei Zhang, Zhang Xintian, Tian-Ze Li, Shuang Tang, Zhen Gao, Cheng Shen, Chang-An Geng, Jing Hu, Li-Hua Su, Xiao-Yan Huang, Yun-Bao Ma, and Ji-Jun Chen
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0303 health sciences ,Artematrolides A–R ,Chemistry ,Stereochemistry ,Cytotoxicity ,Cell migration ,Apoptosis ,Fractionation ,RM1-950 ,Cell cycle ,Artemisia atrovirens ,Adduct ,03 medical and health sciences ,chemistry.chemical_compound ,0302 clinical medicine ,Monomer ,030220 oncology & carcinogenesis ,Guaianolide dimers ,Therapeutics. Pharmacology ,General Pharmacology, Toxicology and Pharmaceutics ,Two-dimensional nuclear magnetic resonance spectroscopy ,030304 developmental biology - Abstract
Leading by cytotoxicity against HepG2 cells, bioactivity-guided fractionation of the EtOAc fraction from Artemisia atrovirens led to the isolation of 18 new guaianolide dimers, artematrolides A–R and lavandiolides A, B, C, H, and J. Eight compounds (1, 4, 10, 12, 13, and 19–21) were unambiguously confirmed by the single-crystal X-ray diffraction analyses, and the others were elucidated based on IR, UV, HRESIMS, 1D and 2D NMR experiments, and comparison of the experimental and calculated ECD data. Structurally, all of them were [4 + 2] Diels–Alder adducts of two monomeric guaianolides. The isolates were evaluated for their cytotoxicity against three human hepatoma cell lines, and 19 compounds demonstrated cytotoxicity against HepG2, SMMC-7721, and Huh7 cell lines. Especially, compounds 1, 12, 14, and 15 exhibited cytotoxicity with IC50 values of 4.4, 3.8, 7.6, and 6.7 μmol/L (HepG2), 9.6, 4.6, 6.6, and 6.0 μmol/L (SMMC-7721), and 7.6, 4.5, 6.9, and 5.6 μmol/L (Huh7), respectively. Notably, compound 12 showed the most promising activity against three human hepatoma cell lines and dose-dependently inhibited cell migration and invasion, induced G2/M cell cycle arrest and cell apoptosis in HepG2 cells, down-regulated the expression of BCL-2 and PARP-1, and activated PARP-1 to up-regulate the expression of cleaved-PARP-1.
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- 2021
4. Tsaokols A and B, unusual flavanol-monoterpenoid hybrids as α-glucosidase inhibitors from Amomum tsao-ko
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Chang-An Geng, Tian-Ze Li, Xue-Mei Zhang, Xuke Zhang, Xiao-Feng He, Jing Hu, Ji-Jun Chen, and Yuanqiang Guo
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chemistry.chemical_classification ,Circular dichroism ,Dried fruit ,biology ,Bicyclic molecule ,Chemistry ,Stereochemistry ,02 engineering and technology ,General Chemistry ,010402 general chemistry ,021001 nanoscience & nanotechnology ,biology.organism_classification ,01 natural sciences ,Amomum ,0104 chemical sciences ,Enzyme ,Docking (molecular) ,Michael reaction ,medicine ,0210 nano-technology ,Acarbose ,medicine.drug - Abstract
Tsaokols A (1) and B (2), two complicated flavanol-monoterpenoid hybrids, were isolated from the dried fruits of Amomum tsao-ko under the guidance of LCMS and bioassay. Their structures were determined by extensive spectroscopic analyses and electronic circular dichroism (ECD) calculations. Compounds 1 and 2 shared a flavanol backbone fused with 5/7 and 5/6 bicyclic monoterpenoid scaffolds, which were biogenetically condensed by Michael addition and acetalization. Compounds 1 and 2 exhibited significant α-glucosidase inhibitory activity with IC50 values of 18.8 and 38.6 μmol/L (acarbose, IC50 = 213 μmol/L). Docking study supported the strong interactions of 1 and 2 bonding with enzyme by mainly hydrophobic and hydrogen-bond effects. Compounds 1 and 2 could be fast distinguished by the diagnostic ions at m/z 289 and 313 in negative MS2 experiments.
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- 2021
5. Trimeric and dimeric sesquiterpenoids from Artemisia atrovirens and their cytotoxicities
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Xue-Mei Zhang, Jin-Ping Wang, Xiao-Yan Huang, Li-Hua Su, Chang-An Geng, Tian-Ze Li, Yun-Bao Ma, and Ji-Jun Chen
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010405 organic chemistry ,Stereochemistry ,Chemistry ,Organic Chemistry ,Ic50 values ,Artemisia atrovirens ,Huh7 cell ,010402 general chemistry ,Cytotoxicity ,01 natural sciences ,0104 chemical sciences - Abstract
Two sesquiterpenoid trimers, artematrotrimers A (1) and B (2), and two sesquiterpenoid dimers, artematrodimers A (3) and B (4), possessing unprecedented scaffolds with a methylene-bridged connection were identified from Artemisia atrovirens. Their structures and absolute stereochemistry were determined by comprehensive spectroscopic data, single-crystal X-ray diffraction analyses, and ECD calculations. Compounds 1–4 represent a new type of sesquiterpenoid oligomers featuring the connections between hetero sesquiterpenoid units via one or two C–C bonds. A possible biosynthetic pathway for 1–4 was also proposed. Compound 3 showed obvious cytotoxicity against HepG2 and Huh7 cell lines with IC50 values of 21.9 and 22.6 μM, respectively.
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- 2021
6. Artatrovirenols A and B: Two Cagelike Sesquiterpenoids from Artemisia atrovirens
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Li-Hua Su, Xue-Mei Zhang, Xiao-Yan Huang, Chang-An Geng, Ji-Jun Chen, Yun-Bao Ma, and Tian-Ze Li
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Quantum chemical ,chemistry.chemical_compound ,Chemistry ,Dodecane ,Stereochemistry ,Intramolecular force ,Organic Chemistry ,Artemisia atrovirens ,Hepatoma cell ,Cytotoxicity ,Cycloaddition - Abstract
Artatrovirenols A and B (1 and 2), two novel cagelike sesquiterpenoids, possess a unique 5/5/6/5/5-pentacyclic and a 5/5/6/5-tetracyclic system with an unprecedented tetracyclo[5.3.1.1.4,1101,5]dodecane scaffold from Artemisia atrovirens. The structures of compounds 1 and 2 including their absolute stereochemistry were elucidated through extensive spectroscopic analyses, X-ray crystallography, and quantum chemical calculations. Plausible biosynthetic pathways for the new isolates were proposed from the naturally occurring arglabin (3) via the key intramolecular Diels-Alder cycloaddition. Compound 1 showed cytotoxicity against three human hepatoma cell lines (HepG2, SMMC-7721, and Huh7) with half maximal inhibitory concentration values of 123.8, 44.0, and 142.6 μΜ, respectively.
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- 2020
7. Nineteen New Flavanol–Fatty Alcohol Hybrids with α-Glucosidase and PTP1B Dual Inhibition: One Unusual Type of Antidiabetic Constituent from Amomum tsao-ko
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Tian-Ze Li, Yuanqiang Guo, Xiao-Feng He, Chang-An Geng, Xue-Mei Zhang, Jing Hu, Xuke Zhang, and Ji-Jun Chen
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biology ,Dried fruit ,Stereochemistry ,Fatty alcohol ,Alcohol ,General Chemistry ,biology.organism_classification ,Amomum ,chemistry.chemical_compound ,chemistry ,medicine ,Hemiacetal ,Enzyme kinetics ,General Agricultural and Biological Sciences ,IC50 ,Acarbose ,medicine.drug - Abstract
The dried fruits of Amomum tsao-ko were first revealed to have hypoglycemic effects on db/db mice at a concentration of 200 mg/kg. In order to clarify the antidiabetic constituents, 19 new flavanol-fatty alcohol hybrids, tsaokoflavanols A-S (1-19), were isolated and determined by extensive spectroscopic data and ECD calculations. Most of the compounds showed α-glucosidase and PTP1B dual inhibition, among which 1, 2, 6, 11, and 18 exhibited obvious activity against α-glucosidase with IC50 values of 5.2-9.0 μM, 20-35 times stronger than that of acarbose (IC50, 180.0 μM); meanwhile, 6, 10-12, and 19 were PTP1B/TCPTP-selective inhibitors with IC50 values of 56.4-80.4 μM, 2-4 times stronger than that of suramin sodium (IC50, 200.5 μM). Enzyme kinetics study indicated that compounds 1, 2, 6, and 11 were α-glucosidase and PTP1B mixed-type inhibitors with Ki values of 13.0, 11.7, 2.9, and 5.3 μM and 142.3, 88.9, 39.2, and 40.8 μM, respectively. Docking simulations proved the importance of hemiacetal hydroxy, the orientation of 3,4-dihydroxyphenyl, and the length of alkyl in binding with α-glucosidase and PTP1B.
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- 2020
8. Artemyrianolides A–S, Cytotoxic Sesquiterpenoids from Artemisia myriantha
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Tian-Ze Li, Yun-Bao Ma, Cheng Shen, Chang-An Geng, Zhang Xintian, Ji-Jun Chen, Xue-Mei Zhang, Li-Hua Su, Zhen Gao, Shuang Tang, and Xiao-Yan Huang
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Pharmacology ,biology ,Bicyclic molecule ,010405 organic chemistry ,Chemistry ,Stereochemistry ,Artemisia myriantha ,Organic Chemistry ,Pharmaceutical Science ,Asteraceae ,biology.organism_classification ,01 natural sciences ,0104 chemical sciences ,Analytical Chemistry ,010404 medicinal & biomolecular chemistry ,Complementary and alternative medicine ,Cell culture ,Hepg2 cells ,Drug Discovery ,Molecular Medicine ,Cytotoxic T cell ,Cytotoxicity ,Two-dimensional nuclear magnetic resonance spectroscopy - Abstract
Random screening suggested that the EtOH extract of Artemisia myriantha (Asteraceae) and its EtOAc fraction had cytotoxicity against HepG2 cells with inhibitory ratios of 30.6% and 53.5% at 50.0 μg/mL. Bioassay-guided isolation of the most active fractions (Fr. C and Fr. D) afforded 19 new sesquiterpenolides, artemyrianolides A-S (1-19), involving 13 germacranolides (1-13), four guaianolides (14-17), and two eudesmanolides (18 and 19), together with 16 known sesquiterpenoids (20-35). The new compounds were characterized by physical data analyses (HRESIMS, IR, 1D and 2D NMR, ECD), and the absolute configurations of compounds 1, 2, and 11 were determined by X-ray crystallography. Structurally, compounds 2 and 11-13 maintain an uncommon cis-fused 10/5 bicyclic system and compound 12 possesses an unusual (7S) configuration. Twenty of the compounds exhibited cytotoxicity against HepG2, Huh7, and SMMC-7721 cell lines. Compound 9 showed cytotoxic activity on both HepG2 and Huh7 cells with IC50 values of 8.6 and 8.8 μM, and compounds 8 and 33 showed cytotoxicity to the three human hepatoma cell lines with IC50 values of 4.9 and 7.4 μM (HepG2), 4.3 and 7.8 μM (Huh7), and 3.1 and 9.8 μM (SMMC-7721), respectively.
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- 2020
9. Artemyrianins A–G from Artemisia myriantha and Their Cytotoxicity Against HepG2 Cells
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Cheng Shen, Yun-Bao Ma, Tian-Ze Li, Xue-Mei Zhang, Ji-Jun Chen, Jing Hu, Chang-An Geng, Shuang Tang, Li-Hua Su, and Zhen Gao
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Norlignans ,Stereochemistry ,Cytotoxicity ,Pharmacology toxicology ,Plant Science ,Toxicology ,Artemyrianins A–G ,Biochemistry ,Analytical Chemistry ,Ic50 values ,HepG2 cells ,Pharmacology ,Artemisia myriantha ,biology ,Chemistry ,Organic Chemistry ,Sesquiterpenoids ,Botany ,Asteraceae ,biology.organism_classification ,Hepg2 cells ,QK1-989 ,Plant biochemistry ,Original Article ,Two-dimensional nuclear magnetic resonance spectroscopy ,Food Science - Abstract
Abstract Four new sesquiterpenoids, artemyrianins A–D (1–4), and three new norlignans, artemyrianins E–G (5–7), together with five known compounds (8–12), were isolated from the aerial parts of Artemisia myriantha (Asteraceae). The new compounds were established by spectroscopic data analyses (HRMS, IR, 1D and 2D NMR), and their absolute configurations were confirmed by the single-crystal X-ray diffraction or ECD calculations. The isolates showed cytotoxicity against HepG2 cells with IC50 values ranging from 33.3 to 145.2 μM. Graphic Abstract
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- 2020
10. Artemlavanins A and B from Artemisia lavandulaefolia and Their Cytotoxicity Against Hepatic Stellate Cell Line LX2
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Jing Hu, Cheng Shen, Xiao-Yan Huang, Ji-Jun Chen, Xue-Mei Zhang, Chang-An Geng, Li-Hua Su, Tian-Ze Li, Shuang Tang, and Zhen Gao
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Stereochemistry ,Cytotoxicity ,Plant Science ,Toxicology ,01 natural sciences ,Biochemistry ,Analytical Chemistry ,Artemisia lavandulaefolia ,03 medical and health sciences ,chemistry.chemical_compound ,Laminin ,Hyaluronic acid ,Moiety ,Artemlavanins ,IC50 ,030304 developmental biology ,Pharmacology ,chemistry.chemical_classification ,0303 health sciences ,biology ,010405 organic chemistry ,Organic Chemistry ,Sesquiterpenoids ,Botany ,0104 chemical sciences ,HSC-LX2 ,chemistry ,QK1-989 ,biology.protein ,Hepatic stellate cell ,Original Article ,Two-dimensional nuclear magnetic resonance spectroscopy ,Lactone ,Food Science - Abstract
Abstract Two new sesquiterpenoids, artemlavanins A (1) and B (3), together with fifteen known compounds (2 and 4−17) were isolated from the EtOH extract of Artemisia lavandulaefolia. The structures of new compounds were elucidated by extensive spectroscopic analyses (HRESIMS, 1D and 2D NMR) and ECD calculations. Compound 1 was a sesquiterpenoid lactone possessing a rearranged eudesmane skeleton; compounds 2–5, 6–8, 9 and 10–12 belonged to the eudesmane, guaiane, oppositane and farnesane sesquiterpenoids, respectively; compounds 13–17 were the phenyl derivatives with a 4-hydroxyacetophenone moiety. Twelve compounds (1–3, 5–7, 10–12, 14, 15 and 17) displayed cytotoxicity against hepatic stellate cell line LX2 (HSC-LX2) with IC50 values ranging from 35.1 to 370.3 μM. Compounds 2, 7, 10–12 and 17 exhibited the stronger cytotoxicity than silybin (IC50, 169.6 μM) with IC50 values of 82.1, 35.1, 95.0, 83.8, 81.6 and 90.1 μM. Compound 7 as the most active one showed significant inhibition on the deposition of human collagen type I (Col I), human hyaluronic acid (HA) and human laminin (HL) with IC50 values of 10.7, 24.5 and 13.3 μM. Graphic Abstract
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- 2020
11. Spiroseoflosterol, a Rearranged Ergostane-Steroid from the Fruiting Bodies of Butyriboletus roseoflavus
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Xiao-Yan Huang, Gang Wu, Yun-Bao Ma, Ji-Jun Chen, Li-Hua Su, Tian-Ze Li, Zhu-Liang Yang, Xue-Mei Zhang, and Chang-An Geng
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Pharmacology ,Butyriboletus roseoflavus ,Ergostane ,Stereochemistry ,medicine.medical_treatment ,Organic Chemistry ,Pharmaceutical Science ,Analytical Chemistry ,Semipinacol rearrangement ,Steroid ,chemistry.chemical_compound ,Complementary and alternative medicine ,chemistry ,Drug Discovery ,medicine ,Ic50 values ,Molecular Medicine - Abstract
Spiroseoflosterol (1), a 7(8→9)-abeo-ergostane steroid with a unique spiro[4.5]decan-6-one system, was isolated from the fruiting bodies of Butyriboletus roseoflavus. Its structure was determined by interpretation of comprehensive spectroscopic, X-ray, and computational data. A plausible biogenetic pathway for spiroseoflosterol (1) was postulated based on a key semipinacol rearrangement. Compound 1 was cytotoxic to HepG2 and Huh7/S (sorafenib-resistant Huh7) with IC50 values of 9.1 and 6.2 μM, respectively.
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- 2020
12. Inhibition of Hypothalamic Inhibitor κB Kinase β/Nuclear Transcription Factor κB Pathway Attenuates Metabolism and Cardiac Dysfunction in Type 2 Diabetic Rats
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Ying Li, Kai-Li Liu, Tian-Ze Sun, Guo-Qing Zhu, Yu-Ming Kang, Hong-Bao Li, Xiao-Jing Yu, Xiao-Lian Shi, Hong-Li Gao, Yan-Mei Chen, and Jie Qi
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Blood Glucose ,Male ,Cardiac function curve ,medicine.medical_specialty ,Diabetic Cardiomyopathies ,Endocrinology, Diabetes and Metabolism ,030209 endocrinology & metabolism ,Inflammation ,Thiophenes ,medicine.disease_cause ,030218 nuclear medicine & medical imaging ,Proinflammatory cytokine ,Rats, Sprague-Dawley ,Pathogenesis ,03 medical and health sciences ,Cellular and Molecular Neuroscience ,0302 clinical medicine ,Endocrinology ,Internal medicine ,medicine ,Hyperinsulinemia ,Animals ,Protein Kinase Inhibitors ,chemistry.chemical_classification ,Reactive oxygen species ,Arc (protein) ,Endocrine and Autonomic Systems ,business.industry ,Arcuate Nucleus of Hypothalamus ,NF-kappa B ,medicine.disease ,I-kappa B Kinase ,Rats ,Disease Models, Animal ,Diabetes Mellitus, Type 2 ,chemistry ,Echocardiography ,Cytokines ,medicine.symptom ,business ,Oxidative stress ,Signal Transduction - Abstract
Background: Inflammation and oxidative stress play important roles in energy imbalance and its complications. Recent research indicates that hypothalamic inflammation may contribute to the pathogenesis of metabolic syndrome and cardiac dysfunction, but the mechanisms remain unclear. We hypothesized that suppression of the proinflammatory IKKβ/NF-κB pathway in the hypothalamus can improve energy balance and cardiac function in type 2 diabetic (T2D) rats. Methods: Normal and T2D rats received bilateral hypothalamic arcuate nucleus (ARC) infusions of the IKKβ inhibitor SC-514 or vehicle via osmotic minipump. Metabolic phenotyping, immunohistochemical analyses, and biochemical analyses were used to investigate the outcomes of inhibition of the hypothalamic IKKβ. Echocardiography and glucometer were used for measuring cardiac function and blood glucose, respectively. Blood samples were collected for the evaluation of circulating proinflammatory cytokines. Heart was harvested for cardiac morphology evaluations. The ARC was harvested and analyzed for IKKβ, NF-κB, proinflammatory cytokines, reactive oxygen species (ROS), and NAD(P)H (gp91phox, p47phox) oxidase activity levels and neuropeptides. Results: Compared with normal rats, T2D rats were characterized by hyperglycemia, hyperinsulinemia, glucose intolerance, cardiac dysfunction, as well as higher ARC levels of IKKβ, NF-κB, proinflammatory cytokines, ROS, gp91phox, and p47phox. ARC infusion of the IKKβ inhibitor SC-514 attenuated all these changes in T2D rats, but not in normal rats. Conclusions: Our results indicate that the hypothalamic IKKβ/NF-κB pathway plays a key role in modulating energy imbalance and cardiac dysfunction, suggesting its potential therapeutic role during type 2 diabetes mellitus.
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- 2019
13. Sirt3‐dependent deacetylation of COX‐1 counteracts oxidative stress‐induced cell apoptosis
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Tao Zhang, Yue-Hong Zhang, Gao-Xiao Zhang, Yang-Fan Zhou, Long-Fang Tu, Hiroshi Kurihara, Yu-Lin Guo, Wei-Qi Lu, Ling-Fang Cao, Rong-Rong He, Yi-Fang Li, and Tian-Ze Zhang
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0301 basic medicine ,SIRT3 ,Amidines ,Mitochondrion ,medicine.disease_cause ,Biochemistry ,Brain Ischemia ,Rats, Sprague-Dawley ,Mice ,03 medical and health sciences ,0302 clinical medicine ,Sirtuin 3 ,Genetics ,medicine ,Animals ,Sirtuins ,Cytochrome c oxidase ,Molecular Biology ,Neurons ,biology ,Chemistry ,Membrane Proteins ,Hydrogen Peroxide ,Rats ,Specific Pathogen-Free Organisms ,Cell biology ,030104 developmental biology ,Gene Expression Regulation ,Apoptosis ,Acetylation ,Reperfusion Injury ,Sirtuin ,Cyclooxygenase 1 ,NIH 3T3 Cells ,biology.protein ,030217 neurology & neurosurgery ,Oxidative stress ,Biotechnology - Abstract
The mitochondrial complexes are prone to sirtuin (Sirt)3-mediated deacetylation modification, which may determine cellular response to stimuli, such as oxidative stress. In this study, we show that the cytochrome c oxidase (COX)-1, a core catalytic subunit of mitochondrial complex IV, was acetylated and deactivated both in 2,2'-azobis(2-amidinopropane) dihydrochloride-treated NIH/3T3 cells and hydrogen peroxide-treated primary neuronal cells, correlating with apoptotic cell death induction by oxidative stress. Inhibition of Sirt3 by small interfering RNA or the inhibitor nicotinamide induced accumulation of acetylation of COX-1, reduced mitochondrial membrane potential, and increased cell apoptosis. In contrast, overexpression of Sirt3 enhanced deacetylation of COX-1 and inhibited oxidative stress-induced apoptotic cell death. Significantly, rats treated with ischemia/reperfusion injury, a typical oxidative stress-related disease, presented an inhibition of Sirt3-induced hyperacetylation of COX-1 in the brain tissues. Furthermore, K13, K264, K319, and K481 were identified as the acetylation sits of COX-1 in response to oxidative stress. In conclusion, COX-1 was discovered as a new deacetylation target of Sirt3, indicating that the Sirt3/COX-1 axis is a promising therapy target of stress-related diseases.-Tu, L.-F., Cao, L.-F., Zhang, Y.-H., Guo, Y.-L., Zhou, Y.-F., Lu, W.-Q., Zhang, T.-Z., Zhang, T., Zhang, G.-X., Kurihara, H., Li, Y.-F., He, R.-R. Sirt3-dependent deacetylation of COX-1 counteracts oxidative stress-induced cell apoptosis.
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- 2019
14. Biomimetic Synthesis of Lavandiolides H, I, and K and Artematrolide F via Diels-Alder Reaction
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Xue-Mei Zhang, Jin-Ping Wang, Ji-Jun Chen, Chang-An Geng, Tian-Ze Li, Yun-Bao Ma, Xiao-Tong Yang, and Li-Hua Su
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Chemistry ,Stereochemistry ,Organic Chemistry ,Trimer ,Biochemistry ,chemistry.chemical_compound ,Spirolactone ,Tetramer ,Biomimetic synthesis ,Yield (chemistry) ,Moiety ,Physical and Theoretical Chemistry ,Cytotoxicity ,Diels–Alder reaction - Abstract
The biomimetic synthesis of guaianolide dimers lavandiolides H, I, and K and artematrolide F containing a spirolactone moiety has been accomplished for the first time from naturally abundant arglabin in four to six steps with an overall yield up to 60%, and a series of natural product-like guaianolide dimers, trimer, and tetramer were also successfully synthesized. Notably, the trimeric compound exhibited antihepatoma cytotoxicity more potent than that of sorafenib with IC50 values of 6.2 μM (HepG2), 6.8 μM (Huh7), and 7.2 μM (SK-HEP-1).
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- 2021
15. Artematrovirenins A-P, guaiane-type sesquiterpenoids with cytotoxicities against two hepatoma cell lines from Artemisia atrovirens
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Shuang Tang, Zhen Gao, Li-Hua Su, Yun-Bao Ma, Chang-An Geng, Ji-Jun Chen, Tian-Ze Li, Cheng Shen, Xue-Mei Zhang, Xiao-Yan Huang, Xin Zhang, and Jing Hu
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Stereochemistry ,Cell Survival ,01 natural sciences ,Biochemistry ,Sesquiterpenes, Guaiane ,Structure-Activity Relationship ,Cell Line, Tumor ,Drug Discovery ,Ic50 values ,Humans ,Cytotoxicity ,Molecular Biology ,Density Functional Theory ,Cell Proliferation ,Dose-Response Relationship, Drug ,Molecular Structure ,010405 organic chemistry ,Chemistry ,Organic Chemistry ,Huh7 cell ,Artemisia atrovirens ,Antineoplastic Agents, Phytogenic ,0104 chemical sciences ,010404 medicinal & biomolecular chemistry ,Artemisia ,Hepg2 cells ,Drug Screening Assays, Antitumor ,Hepatoma cell ,Sesquiterpenes - Abstract
Random screening revealed that the EtOH extract of Artemisia atrovirens showed significant cytotoxicity against two human hepatoma cell lines (HepG2 and Huh7) with the inhibitory ratio of 98.9% and 99.7% at the concentration of 100 μg/mL. Further bioactivity-guided isolation of active fraction led to 16 new guaiane-type sesquiterpenoids, artematrovirenins A–P (1–16). Their structures were elucidated by extensive spectroscopic data. The absolute stereochemistry of compounds 1 and 14 was determined by single-crystal X-ray diffraction analyses. Pharmacological evaluation suggested that five compounds (3, 5, 8, 10, and 15) exhibited cytotoxicity, compounds 3 and 5 displayed cytotoxicity against HepG2 cell line with an IC50 values of 8.0 and 16.0 μM, as well as against Huh7 cell line with values of 18.2 and 32.2 μM.
- Published
- 2021
16. Polybenzyls from Gastrodia elata, their agonistic effects on melatonin receptors and structure-activity relationships
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Li-Hua Su, Zhen-Tao Deng, Xiao-Tong Yang, Tian-Ze Li, Zhen Gao, Xiao-Feng He, Chang-An Geng, Si-Yue Chen, Yun-Bao Ma, Xue-Mei Zhang, Xiao-Yan Huang, and Ji-Jun Chen
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Clinical Biochemistry ,Receptors, Melatonin ,Pharmaceutical Science ,01 natural sciences ,Biochemistry ,Melatonin ,Structure-Activity Relationship ,Drug Discovery ,medicine ,Agonistic behaviour ,Humans ,Medicine, Chinese Traditional ,Receptor ,Molecular Biology ,Gastrodia ,Dose-Response Relationship, Drug ,Molecular Structure ,biology ,Plant Extracts ,010405 organic chemistry ,Chemistry ,Organic Chemistry ,biology.organism_classification ,Gastrodia elata ,0104 chemical sciences ,Molecular Docking Simulation ,010404 medicinal & biomolecular chemistry ,HEK293 Cells ,Molecular Medicine ,Pharmacophore ,Drugs, Chinese Herbal ,medicine.drug - Abstract
Gastrodia elata is a famous traditional Chinese herb with medicinal and edible application. In this study, nine polybenzyls ( 1 − 9 ), including six new ones ( 2 − 5 , 7 and 9 ), were isolated from the EtOAc extract of G. elata . Five compounds 1 , 3 , 4 , 6 and 8 were found to activate melatonin receptors. Especially, compound 1 showed agonistic effects on MT 1 and MT 2 receptors with EC 50 values of 237 and 244 μM. For better understanding their structure-activity relationships (SARs), ten polybenzyl analogs were further synthesized and assayed for their activities on melatonin receptors. Preliminary SARs study suggested that two para -hydroxy groups were the key pharmacophore for maintaining activity. Molecular docking simulations verified that compound 1 could strongly interact with MT 2 receptor by bonding to Phe 118, Gly 121, His 208, Try 294 and Ala 297 residues.
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- 2019
17. Facile synthesis of metal–organic framework-derived SiW12@Co3O4 and its peroxidase-like activity in colorimetric assay
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Tian-Ze Li, Jian-Hua Wang, Ming-Li Chen, Shaorong Liu, Meng-Meng Wang, Ting Yang, Wei Shi, and Shuang E
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chemistry.chemical_classification ,Detection limit ,Aqueous solution ,Chemistry ,010401 analytical chemistry ,Glucose detection ,02 engineering and technology ,021001 nanoscience & nanotechnology ,01 natural sciences ,Biochemistry ,Combinatorial chemistry ,0104 chemical sciences ,Analytical Chemistry ,law.invention ,Enzyme ,law ,Peroxidase like ,Electrochemistry ,Environmental Chemistry ,Metal-organic framework ,Calcination ,0210 nano-technology ,Spectroscopy ,Strong binding - Abstract
Over the past few years, artificial enzymes have attracted enormous attention due to their high stabilities and cost-effective productions. In this work, metal-organic framework-derived SiW12@Co3O4 was synthesized in large quantities by stirring the mixture at ambient temperature and calcination. The obtained SiW12@Co3O4 exhibited a highly inherent peroxidase-like activity and excellent stability. Kinetic studies demonstrated that the synthesized SiW12@Co3O4 had a strong binding affinity to 3,3',5,5'-tetramethylbenzidine (TMB), stronger than HRP had. Specifically, the peroxidase-like activity of SiW12@Co3O4 in an aqueous solution was well maintained after incubation at an elevated temperature, at an extreme pH and for a long time. A SiW12@Co3O4-based method was further developed for H2O2 and one-pot glucose detection with good sensitivity and reliability. The facile synthesis approach is expected to facilitate the practical use of metal-organic frameworks and their derivatives as enzyme mimics in the future.
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- 2019
18. Anti-hepatitis B virus effects of the traditional Chinese herb Artemisia capillaris and its active enynes
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Tian-Ze Li, Xiao-Yan Huang, Tong-Hua Yang, Yun-Bao Ma, Chang-An Geng, Xue-Mei Zhang, Ji-Jun Chen, and Jing Yang
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DNA Replication ,Hepatitis B virus ,HBsAg ,food.ingredient ,Phytochemicals ,Virus Replication ,medicine.disease_cause ,Antiviral Agents ,01 natural sciences ,Virus ,chemistry.chemical_compound ,food ,Drug Discovery ,medicine ,Humans ,Glycosyl ,Hepatitis B e Antigens ,Medicine, Chinese Traditional ,Pharmacology ,Hepatitis B Surface Antigens ,Traditional medicine ,Plant Extracts ,010405 organic chemistry ,virus diseases ,Hep G2 Cells ,Plant Components, Aerial ,digestive system diseases ,In vitro ,0104 chemical sciences ,010404 medicinal & biomolecular chemistry ,Artemisia ,chemistry ,HBeAg ,Cell culture ,Alkynes ,Herb ,DNA, Viral - Abstract
Ethnopharmacological relevance Artemisia capillaris (Yin-Chen) is a famous traditional Chinese medicine (TCM) for treating acute and chronic hepatitis in China. Enynes are one type of characteristic constituents in this herb, while their anti-hepatitis B virus (anti-HBV) properties have not been systemically investigated. Aim of the study This study is to reveal the active part of A. capillaris, and systemically investigate the enynes and their anti-HBV activity. Materials and methods The total extract and each fraction of A. capillaris were assayed for the anti-HBV activity to reveal the active part. Bioassay-guided fractionation using various chromatographic techniques yielded the enynes, whose structures were elucidated by spectroscopic analyses and ECD calculations. The anti-HBV properties inhibiting HBsAg and HBeAg secretions and HBV DNA replication were evaluated on HepG 2.2.15 cell line in vitro. Results ACT-2 and ACT-3 was revealed to be the respective active and toxic part of A. capillaris. Twelve enynes (1–12) involving four new ones (1–4) and two unusual enyne analogs (13–14) were isolated from the active part (ACT-2). All the isolates were assayed for their anti-HBV activity, and the preliminary structure-activity relationships were summarized based on the structural features. In particular, compound 4 could significantly inhibit the secretions of HBsAg and HBeAg, and HBV DNA replication with IC50 values of 197.2 (SI > 5.1), 48.7 (SI > 20.5) and 9.8 (SI > 102) μM. Conclusions Enynes are responsible for the anti-HBV effects of A. capillaris. Hydroxyl and glycosyl groups are preferable for maintaining activity. This is the first time to systematically investigate the anti-HBV activity of enynes in A. capillaris, which provides valuable information for understanding the ethnopharmacological application of Yin-Chen.
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- 2018
19. Synthesis and anti-fibrotic effects of santamarin derivatives as cytotoxic agents against hepatic stellate cell line LX2
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Ji-Jun Chen, Tian-Ze Li, Jin-Jin Sun, Cheng Shen, Xiao-Yan Huang, Chang-An Geng, Jin-Ping Wang, and Dong Xue
- Subjects
Liver Cirrhosis ,Anti fibrotic ,Clinical Biochemistry ,Pharmaceutical Science ,01 natural sciences ,Biochemistry ,Cell Line ,Extracellular matrix ,chemistry.chemical_compound ,Structure-Activity Relationship ,Laminin ,Drug Discovery ,Hyaluronic acid ,Hepatic Stellate Cells ,Humans ,Cytotoxicity ,Molecular Biology ,Santamarin ,chemistry.chemical_classification ,biology ,Dose-Response Relationship, Drug ,Molecular Structure ,010405 organic chemistry ,Chemistry ,Cytotoxins ,Organic Chemistry ,Molecular biology ,0104 chemical sciences ,010404 medicinal & biomolecular chemistry ,Hepatic stellate cell ,biology.protein ,Molecular Medicine ,Sesquiterpenes ,Lactone - Abstract
Liver fibrosis is a final result of extensive deposition of extracellular matrix (ECM) and starts with the activation and proliferation of hepatic stellate cells (HSCs). Our previous study showed that eudesmane sesquiterpenoid santamarin had cytotoxicity against hepatic stellate cell line LX2 (HSC-LX2) with IC50 values of 16.5 ± 0.7 μM. To explore the structure–activity relationships, twenty-six derivatives were synthesized by modifying the hydroxyl group, double-bond and unsaturated lactone. Cytotoxicity evaluation suggested that eight derivatives (6, 9, 13, 17, 20 and 25–27) increased activity against HSC-LX2. Especially, derivatives 17, 20 and 25 displayed obvious cytotoxicity with IC50 values of 6.4 ± 0.4, 4.6 ± 0.1, and 3.5 ± 0.1 μM, which were 3 to 5-fold higher than santamarin. Preliminary mechanisms study revealed that the active compound 20 exhibited more than 8-fold and 6-fold enhancement of inhibitory effect on the deposition of human hyaluronic acid (HA) and human laminin (HL) with IC50 values of 7.6 ± 0.6 and 3.3 ± 1.2 μM.
- Published
- 2021
20. Synthesis of nigranoic acid and manwuweizic acid derivatives as HDAC inhibitors and anti-inflammatory agents
- Author
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Tian-Ze Shen, Wei-Lie Xiao, Xing-Jie Zhang, Xiao-Li Li, Ruihan Zhang, Yi-Man Cui, Dong-Xuan Ni, Yi-Ming Li, Han-Dong Sun, and Qi Wang
- Subjects
Cell Survival ,Inflammasomes ,Anti-Inflammatory Agents ,01 natural sciences ,Biochemistry ,Histone Deacetylases ,Cell Line ,chemistry.chemical_compound ,Mice ,Structure-Activity Relationship ,Lactate dehydrogenase ,Drug Discovery ,NLR Family, Pyrin Domain-Containing 3 Protein ,Animals ,Viability assay ,Molecular Biology ,IC50 ,chemistry.chemical_classification ,Hydroxamic acid ,Dose-Response Relationship, Drug ,Molecular Structure ,010405 organic chemistry ,Organic Chemistry ,HDAC8 ,Triterpenes ,0104 chemical sciences ,Histone Deacetylase Inhibitors ,Isoenzymes ,010404 medicinal & biomolecular chemistry ,Enzyme ,chemistry ,Acetylation ,Docking (molecular) - Abstract
As a successful anti-tumor drug target, the family of histone deacetylases (HDACs) is also a critical player in immune response, making the research of anti-inflammatory HDAC inhibitors an attractive new focus. In this report, triterpenoids nigranoic acid (NA) and manwuweizic acid (MA) were identified as HDAC inhibitors through docking-based virtual screening and enzymatic activity assay. A series of derivatives of NA and MA were synthesized and assessed for their biological effects. As a result, hydroxamic acid derivatives of NA and MA showed moderately increased activity for HDAC1/2/4/6 inhibition (the lowest IC50 against HDAC1 is 1.14 μM), with no activity against HDAC8. In J774A.1 macrophage, compound 1–3, 13 and 17–19 demonstrated inhibitory activity against lactate dehydrogenase (LDH) and IL-1β production, without affecting cell viability. Compound 19 increased the histone acetylation level in J774A.1 cells, as well as inhibited IL-1β maturation and caspase-1 cleavage. These results indicated that compound 19 blocks the activation of NLRP3 inflammasome, probably related to HDAC inhibition. This work provided a natural scaffold for developing low-cytotoxic and anti-inflammatory HDAC inhibitors, as well as a class of tool molecules for studying the relationship between HDACs and NLRP3 activation.
- Published
- 2021
21. Synthesis and biological evaluation of chepraecoxin A derivatives as α-glucosidase inhibitors
- Author
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Tian-Ze Li, Ji-Jun Chen, Chang-An Geng, Xiao-Tong Yang, and Zhen-Tao Deng
- Subjects
Double bond ,Stereochemistry ,Clinical Biochemistry ,Pharmaceutical Science ,Inhibitory postsynaptic potential ,01 natural sciences ,Biochemistry ,Structure-Activity Relationship ,Non-competitive inhibition ,Drug Discovery ,medicine ,Humans ,Glycoside Hydrolase Inhibitors ,Enzyme kinetics ,Molecular Biology ,IC50 ,Biological evaluation ,Acarbose ,chemistry.chemical_classification ,Dose-Response Relationship, Drug ,Molecular Structure ,010405 organic chemistry ,Chemistry ,Organic Chemistry ,Stereoisomerism ,alpha-Glucosidases ,Terpenoid ,0104 chemical sciences ,010404 medicinal & biomolecular chemistry ,Molecular Medicine ,medicine.drug - Abstract
The ent-kaurane diterpenoid chepraecoxin A (CA) obtained in our previous study showed a potential inhibitory activity on α-glucosidase (IC50 274.5 ± 12.5 μM). In order to figure out the structure-activity relationships (SARs), twenty-two derivatives of chepraecoxin A were synthesized by modifying the ester, allyl, double bond and carboxyl groups, and assayed for their α-glucosidase inhibitory activity. Of them, eight compounds (14–17, 19–22) significantly increased activity with IC50 values ranging from 16.1 to 71.4 μM, even higher than the positive control, acarbose (IC50 130.3 μM). Especially, compounds 17, 19 and 21 could inhibit α-glucosidase with IC50 values of 16.9 ± 3.4, 16.1 ± 1.2, and 17.1 ± 0.6 μM, 17-fold higher than CA. The most active compound 19 was proven to be a non-competitive inhibitor with a Ki value of 19.4 μM based on enzyme kinetics study. The primary SARs of CA derivatives were summarized for exploring antidiabetic candidates.
- Published
- 2019
22. Synthesis and biological evaluation of magnolol derivatives as melatonergic receptor agonists with potential use in depression
- Author
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Yan Dexiu, Tong-Hua Yang, Xiao-Yan Huang, Ji-Jun Chen, Yun-Bao Ma, Xue-Mei Zhang, Chang-An Geng, and Tian-Ze Li
- Subjects
Male ,0301 basic medicine ,Pharmacology ,Lignans ,Rats, Sprague-Dawley ,Mice ,03 medical and health sciences ,chemistry.chemical_compound ,0302 clinical medicine ,Drug Discovery ,Animals ,Humans ,Depression ,Receptor, Melatonin, MT2 ,Chemistry ,Receptor, Melatonin, MT1 ,Biphenyl Compounds ,Organic Chemistry ,Brain ,General Medicine ,Antidepressive Agents ,Acute toxicity ,Tail suspension test ,Magnolol ,Melatonergic ,HEK293 Cells ,030104 developmental biology ,Monoamine neurotransmitter ,Hindlimb Suspension ,Antidepressant ,Female ,Lead compound ,030217 neurology & neurosurgery ,Behavioural despair test - Abstract
Depression is associated with high mortality and morbidity rates worldwide. By our random screening, it was first revealed that 23 magnolol derivatives were synthesized followed by in vitro and in vivo evaluation of their antidepressive potential. Compound 7c was found to be the most promising compound, with EC50 values of 396.5 and 383.0 μM agitating on MT1 and MT2 receptors, respectively. Additionally, we carried out in vivo experiments to confirm the efficacy and safety of compound 7c; the compound was found to be orally bioavailable and highly effective, leading to a significant reduction of immobility time in a mouse model of depression (forced swimming test and tail suspension test); the acting mechanism was explored by determining its effect on the levels of monoamine neurotransmitters and their metabolites in different mice brain regions; the acute toxicity study showed that the 50% lethal dose (LD50) of 7c was higher than 2000 mg/kg, p. o. A total of 25 metabolites of 7c were identified, including 5 metabolites in phase I and 20 metabolites in phase II. Altogether, these results indicate that magnolol derivative 7c is a promising lead compound for the development of a new chemical class of antidepressant drugs.
- Published
- 2018
23. New C 16 -noriridals and formyl-monocycloiridals from the rhizomes of Iris pseudoacorus
- Author
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Chang-An Geng, Xing-Long Chen, Ji-Jun Chen, Xiuqiong Zhang, and Tian-Ze Li
- Subjects
Pharmacology ,010405 organic chemistry ,Chemistry ,Stereochemistry ,General Medicine ,010402 general chemistry ,Ring (chemistry) ,Iris pseudoacorus ,01 natural sciences ,0104 chemical sciences ,Rhizome ,NMR spectra database ,Human tumor ,Drug Discovery ,Ic50 values - Abstract
Four new C16-noriridals (1–4) and two reported C16-noriridals (5–6), together with two new formyl-monocycloiridals (7–8) and three known monocycloiridals (9–11) were isolated from the rhizomes of Iris pseudoacorus. Irispseudoacorins A–D (1–4) and iridojaponals A–B (5–6) were C16-noriridals which shared a 6/5/7 tricyclic ring system (1–2, 5–6) or 6/5 tricyclic ring system (3–4). The formyl-monocycloiridals (7–8) were detected in the crude extracts of I. pseudoacorus by LC-MS analysis which suggested they were originated from natural sources rather than artificial products during the isolation. Their structures were determined by UV, IR, extensive NMR spectra and X-ray diffraction analyses. The known monocycloiridals 9–10 displayed pronounced cytotoxic effects against five human tumor cell lines. The IC50 values of 9 were ranging from 12.63 to 24.69 μM.
- Published
- 2018
24. Artemicapillasins A–N, cytotoxic coumaric acid analogues against hepatic stellate cell LX2 from Artemisia capillaris (Yin-Chen)
- Author
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Zhen Gao, Chang-An Geng, Xiao-Yan Huang, Ji-Jun Chen, and Tian-Ze Li
- Subjects
Dose-Response Relationship, Drug ,Molecular Structure ,Cell Survival ,Chemistry ,Organic Chemistry ,Coumaric acid ,Biochemistry ,Molecular biology ,Collagen Type I ,Structure-Activity Relationship ,chemistry.chemical_compound ,Artemisia ,Drug Discovery ,Hyaluronic acid ,Hepatic Stellate Cells ,Hepatic stellate cell ,Humans ,Bioassay ,Cytotoxic T cell ,Laminin ,Hyaluronic Acid ,Cytotoxicity ,Molecular Biology ,Two-dimensional nuclear magnetic resonance spectroscopy ,IC50 - Abstract
Under the guidance of bioassay against HSC-LX2, the EtOH extract and the EtOAc fraction of Artemisia capillaris (Yin-Chen) exhibited cytotoxic activity against HSC-LX2 with inhibitory ratios of 39.7% and 68.7% at the concentration of 400.0 μg/mL. Bioassay-guided investigation of Fr. D (the active fraction) yielded 14 new coumaric acid analogues, artemicapillasins A–N (1–14). The structures of the isolates were elucidated by spectroscopic analyses involving UV, IR, MS, 1D and 2D NMR spectra and ECD calculations. Cytotoxic activity against HSC-LX2 cells of these isolates was performed to reveal that 12 compounds demonstrated cytotoxicity with inhibitory ratios more than 50% at 400 μM. The most active artemicapillasin B (2) gave an IC50 value of 24.5 μM, which was about 7 times more toxic than the positive drug silybin (IC50, 162.3 μM). Importantly, artemicapillasin B (2) showed significant inhibition on the deposition of human collagen type I (Col I), human laminin (HL) and human hyaluronic acid (HA) with IC50 values of 11.0, 14.4 and 13.8 μM, which was about 7, 11 and 5 times more active than silybin. Artemicapillasin B (2) as an interesting antihepatic fibrosis candidate is worth in-depth study.
- Published
- 2021
25. Nano-octahedral bimetallic Fe/Eu-MOF preparation and dual model sensing of serum alkaline phosphatase (ALP) based on its peroxidase-like property and fluorescence
- Author
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Ming-Li Chen, Xun Liu, Wei Chen, Ning Chu, Mengqi He, Brian Bui, Wei Shi, and Tian-Ze Li
- Subjects
Materials science ,Quenching (fluorescence) ,fungi ,Substrate (chemistry) ,Bioengineering ,Hydrogen Peroxide ,Alkaline Phosphatase ,Fluorescence ,Pyrophosphate ,Catalysis ,Biomaterials ,Hydrolysis ,chemistry.chemical_compound ,Peroxidases ,chemistry ,Mechanics of Materials ,Absorption (chemistry) ,Bimetallic strip ,Fluorescent Dyes ,Peroxidase ,Nuclear chemistry - Abstract
Herein a nano-scale bimetallic Fe/Eu-MOF with a regular octahedral structure was synthesized for the first time. The synthesized Fe/Eu-MOF has both peroxidase-like activity and fluorescence properties. Fe/Eu-MOF can catalyze H2O2 to oxidize the chromogenic substrate TMB to produce blue oxTMB, which has ultraviolet absorption at 652 nm. Unexpectedly, the generated oxTMB can effectively quench the fluorescence of the catalyst Fe/Eu-MOF at 450 nm. The quenching mechanism is mainly the internal filtration effect (IFE), accompanied by static quenching (SQE), Forster resonance energy transfer (FRET) and photoelectron transfer (PET). Fe/Eu-MOF has a high affinity for sodium pyrophosphate (PPi). PPi can be adsorbed to the surface of Fe/Eu-MOF, destroying the structure of Fe/Eu-MOF and inhibiting its catalytic activity, resulting in a decrease in UV absorbance and the decline of fluorescence quenching. In contrast, phosphoric acid (Pi) has almost no effect on the reaction system. Alkaline phosphatase (ALP) can catalyze the hydrolysis of PPi to Pi, thereby reducing the inhibitory effect of PPi. Based on this, we successfully constructed a dual-mode ALP sensor with high selectivity. The linear ranges based on the 652 nm absorption or the fluorescence detection are from 1 to 200 U/L, and the detection limits are 0.6 for the absorption method and 0.9 U/L for the fluorescence method, respectively.
- Published
- 2021
26. Electrospun zirconia-embedded carbon nanofibre for high-sensitive determination of methyl parathion
- Author
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Yong Dai, Jianmao Yang, Tian-ze Zhu, Xiaohong Shang, Guodong Zhu, and Jianyun Liu
- Subjects
Materials science ,Nanoparticle ,chemistry.chemical_element ,Nanotechnology ,02 engineering and technology ,010402 general chemistry ,01 natural sciences ,lcsh:Chemistry ,chemistry.chemical_compound ,Nafion ,Electrochemistry ,medicine ,Cubic zirconia ,Polyvinylpyrrolidone ,Carbon nanofiber ,021001 nanoscience & nanotechnology ,0104 chemical sciences ,Electrochemical gas sensor ,lcsh:Industrial electrochemistry ,lcsh:QD1-999 ,chemistry ,Chemical engineering ,Differential pulse voltammetry ,0210 nano-technology ,Carbon ,lcsh:TP250-261 ,medicine.drug - Abstract
Carbon nanofibers embedded with ultrafine zirconia nanoparticles (ZrO2-CNFs) are fabricated via a new methodology. Polyvinylpyrrolidone (PVP) and polymethylmethacrylate (PMMA) binary polymers containing zirconium n-butoxide are first dissolved in dimethylformamide, and the resulting solution is electrospun and heat-treated. The tetragonal zirconia nanoparticles formed, with a size of 5±2nm in diameter, are uniformly distributed in the carbon nanofibres. Using Nafion as an additive, ZrO2-CNFs are drop-cast onto the glassy carbon electrode (ZrO2-CNF/GCE) and the modified electrode is then applied to detect methyl parathion (MP) using differential pulse voltammetry. Two linear relationships are found at the concentration ranges of 1×10−9–2×10−8g/L and 2×10−8–2×10−7g/L, with a detection limit of 3.4×10−10g/L (S/N>3). The electrospun-based ZrO2-CNF is a very promising coating material for electrochemical sensing of organophosphorus compounds. Keywords: Zirconia nanoparticles, Electrospinning, Carbon nanofiber, Methyl parathion, Electrochemical sensor
- Published
- 2017
27. Bioactivity-guided synthesis of gramine derivatives as new MT1 and 5-HT1A receptors agonists
- Author
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Ji-Jun Chen, Yun-Bao Ma, Tian-Ze Li, Tong-Hua Yang, Jun Zhou, Xing-Long Chen, Chang-An Geng, Xiao-Yan Huang, Xiu-Juan Yin, and Xue-Mei Zhang
- Subjects
0301 basic medicine ,Pharmacology ,Gramine ,Chemistry ,Organic Chemistry ,Pharmaceutical Science ,General Medicine ,Melatonin receptor ,In vitro ,Analytical Chemistry ,03 medical and health sciences ,chemistry.chemical_compound ,030104 developmental biology ,Complementary and alternative medicine ,Drug Discovery ,Agonistic behaviour ,Molecular Medicine ,Receptor ,EC50 - Abstract
Twenty-four gramine derivatives were synthesized and evaluated on MT1 and 5-HT1A receptors in vitro. Among them, seven derivatives (7, 8, 16, 19, 20, 21, and 24) exhibited higher agonisting activities on MT1 or 5-HT1A receptors. Compared with gramine, derivatives 7, 8, 16, 19, 20, 21, and 24 displayed 1.6–3.5-fold increase in agonistic rates on 5-HT1A receptor. Particularly, derivatives 7, 19, and 21 exhibited significant agonistic activities on MT1 and 5-HT1A receptors with EC50 values of 0.51, 0.39, 0.50 mΜ and 0.28, 0.46, 0.23 mΜ, respectively. The preliminary structure–activity relationships of gramine derivatives were summarized for further investigation on MT1 and 5-HT1A receptors as new potential agonists.
- Published
- 2017
28. Global identification strategy based on mass spectrometry for studying protostane triterpenoids in rhizomes of Alisma orientalis
- Author
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Chang-An Geng, Xing-Long Chen, Xiuqiong Zhang, Ji-Jun Chen, and Tian-Ze Li
- Subjects
Chromatography ,Frequency of occurrence ,biology ,010405 organic chemistry ,Chemistry ,010401 analytical chemistry ,Condensed Matter Physics ,Mass spectrometry ,biology.organism_classification ,01 natural sciences ,0104 chemical sciences ,Rhizome ,Triterpenoid ,Alisma ,Ion trap ,Physical and Theoretical Chemistry ,Instrumentation ,Spectroscopy - Abstract
The liquid chromatography hybrid ion trap time-of-flight mass spectrometry (LCMS-IT-TOF) combined with a global identification strategy was applied to studying the protostane triterpenoids (PTs) in the rhizomes of Alisma orientalis in this paper. Initially, the MSn analyses of four reference compounds were performed to summarize the fragmentation rules of PTs. Subsequently, a series of ions of PTs were presented by LC-MSn analyses of the crude extract of alismatis rhizome, from which six ions at m/z 339, 353,365, 381,383 and 397 with high frequency of occurrence were selected as diagnostic ions to classify the peaks. Twenty peaks were classified into six families based on common ions. A network was established for the six families via diagnostic ions. 20 PTs including 1 new compound and 19 known ones were characterized through such strategy, fragmentation rules and references. Ultimately, the detected new compound and two known compounds were isolated from the total extract of A. orientalis under the guide of above method, of which the new compound was identified as 11-deoxylalisol F by MS and NMR spectrum. This systematical investigation on the PTs demonstrated that such a strategy could be widely used in the analysis and separation of natural products. (C) 2017 Elsevier B.V. All rights reserved.
- Published
- 2017
29. (±)-Uncarilins A and B, Dimeric Isoechinulin-Type Alkaloids from Uncaria rhynchophylla
- Author
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Xiao-Yan Huang, Tian-Ze Li, Yun-Bao Ma, Ji-Jun Chen, Bo Hou, Xue-Mei Zhang, and Chang-An Geng
- Subjects
Indoles ,Stereochemistry ,Pharmaceutical Science ,Stereoisomerism ,01 natural sciences ,Indole Alkaloids ,Analytical Chemistry ,Drug Discovery ,Humans ,Nuclear Magnetic Resonance, Biomolecular ,Pharmacology ,Molecular Structure ,biology ,Receptor, Melatonin, MT2 ,010405 organic chemistry ,Chemistry ,Uncaria rhynchophylla ,Receptor, Melatonin, MT1 ,Organic Chemistry ,biology.organism_classification ,0104 chemical sciences ,010404 medicinal & biomolecular chemistry ,Uncaria ,Complementary and alternative medicine ,Molecular Medicine ,Enantiomer ,Two-dimensional nuclear magnetic resonance spectroscopy ,Drugs, Chinese Herbal - Abstract
(±)-Uncarilins A and B (1a/1b and 2a/2b), two pairs of unusual dimeric isoechinulin-type enantiomers with a symmetric four-membered core, were isolated from Uncaria rhynchophylla driven by LCMS-IT-TOF analyses. Their structures were elucidated by extensive 1D and 2D NMR spectra, X-ray diffraction, and ECD spectroscopic data. (−)-Uncarilin B (2a) showed activities on MT1 and MT2 receptors with agonistic rates of 11.26% and 52.44% at a concentration of 0.25 mM.
- Published
- 2017
30. Differential expression of serum proteins in multiple myeloma
- Author
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Yong‑Geun Kwak, Zhe Piao, Tian‑Ze Ma, and Sheng‑Yu Jin
- Subjects
0301 basic medicine ,PSMC1 ,Cancer Research ,Oncogene ,biology ,Chemistry ,Protein subunit ,Haptoglobin ,Serum albumin ,Articles ,General Medicine ,Blood proteins ,Molecular biology ,03 medical and health sciences ,030104 developmental biology ,0302 clinical medicine ,Immunology and Microbiology (miscellaneous) ,030220 oncology & carcinogenesis ,Proteome ,biology.protein ,Antibody - Abstract
The exact cause instigating multiple myeloma (MM) has not been fully elucidated, and the disease has a median survival of 6 months without any treatment. To identify potential biomarkers of MM, serum proteins reflecting alteration in their proteomes were analyzed in 6 patients with MM compared with 6 healthy controls using two-dimensional electrophoresis (2-DE) and matrix-assisted laser desorption/ionization time-of flight mass spectrometry. The most notable differentially expressed proteins were validated by immunoblotting and changes in mRNA expression were evaluated by reverse transcription-quantitative polymerase chain reaction (RT-qPCR). A total of 11 differentially expressed protein spots were found. The expression levels of 7 proteins [Immunoglobulin heavy constant µ; proto-oncogene diffuse B-cell lymphoma (DBL2); 26S protease regulatory subunit 4 (P26s4); serum albumin; haptoglobin; and two unknown proteins with isoelectronic point (pI) of 6.41 and molecular weight of 35.4 kDa, and pI of 8.05 and molecular weight of 27.4 kDa, respectively] were downregulated in MM compared with healthy controls. Expression of gel actin-related protein 2/3 complex subunit 1A (ARPC1A); immunoglobulin heavy constant γ 1; fibrinogen α chain (FGA) fragment D; and zinc finger protein 70 were increased in serum of MM patients. Protein expressions of ARPC1A, FGA, P26s4 and DBL2 were measured by immunoblotting in an independent cohort of 12 MM patients and 10 healthy controls. RT-qPCR analysis demonstrated that ARPC1A expression only mimicked protein expression, whereas FGA, PSMC1 (encoding P26s4) and MCF2 (encoding DBL2) did not exhibit significant changes in mRNA expression between control and MM samples. These proteins represent putative serological biomarkers for patients with MM.
- Published
- 2018
31. Diarylheptanoid-chalcone hybrids with PTP1B and α-glucosidase dual inhibition from Alpinia katsumadai
- Author
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Xiao-Feng He, Ji-Jun Chen, Chang-An Geng, Xue-Mei Zhang, Jing Hu, and Tian-Ze Li
- Subjects
Chalcone ,Stereochemistry ,01 natural sciences ,Biochemistry ,Mice ,Structure-Activity Relationship ,chemistry.chemical_compound ,Chalcones ,Diarylheptanoids ,Drug Discovery ,medicine ,Animals ,Hypoglycemic Agents ,Bioassay ,Glycoside Hydrolase Inhibitors ,Enzyme kinetics ,Enzyme Inhibitors ,Molecular Biology ,IC50 ,Sodium orthovanadate ,Acarbose ,Protein Tyrosine Phosphatase, Non-Receptor Type 1 ,Dose-Response Relationship, Drug ,Molecular Structure ,biology ,010405 organic chemistry ,Chemistry ,Organic Chemistry ,Diarylheptanoid ,alpha-Glucosidases ,Alpinia ,biology.organism_classification ,0104 chemical sciences ,Disease Models, Animal ,010404 medicinal & biomolecular chemistry ,Diabetes Mellitus, Type 2 ,medicine.drug - Abstract
The EtOH extracts of the dried seeds of Alpinia katsumadai were revealed with hypoglycemic effects on db/db mice at the concentration of 200 mg/kg. In order to clarify the antidiabetic constituents, 16 new diarylheptanoid-chalcone hybrids, katsumadainols A1−A16 (1–16), together with 13 known analogues (17–29), were isolated from A. katsumadai under the guidance of bioassay. Most of the compounds showed α-glucosidase and PTP1B dual inhibition, among which compounds 1–3, 5–7, 11–14, 21–25, and 27 showed PTP1B/TCPTP selective inhibition with IC50 values ranging from 22.0 to 96.7 μM, which were 2–10 times more active than sodium orthovanadate (IC50, 215.7 μM). All compounds exhibited obvious inhibition against α-glucosidase with IC50 values of 2.9–29.5 μM, indicating 6–59 times more active than acarbose (IC50, 170.9 μM). Study of enzyme kinetics indicated compounds 1, 3, and 12 were PTP1B and α-glucosidase mixed-type inhibitors with Ki values of 13.1, 12.9, 21.6 μM, and 4.9, 7.4, 3.4 μM, respectively.
- Published
- 2021
32. Highly Stable Eu(III) and Tb(III) Complexes Based on Triarylborane-Functionalized Cyclen Derivatives as Visual Temperature Probes and White-Light Emitters
- Author
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Soren K. Mellerup, Tian-Ze Wu, Li-Xia Cao, Jin-Bao Peng, Tai Peng, Nan Wang, Guo-Qiang Yang, Hee-Jun Park, and Suning Wang
- Subjects
Lanthanide ,010405 organic chemistry ,Dual emission ,010402 general chemistry ,Photochemistry ,01 natural sciences ,Atomic and Molecular Physics, and Optics ,Bright-white ,0104 chemical sciences ,Electronic, Optical and Magnetic Materials ,Ion ,chemistry.chemical_compound ,Cyclen ,chemistry ,White light ,Light emission - Abstract
New and highly stable Eu(III) and Tb(III) complexes based on two triarylborane functionalized cyclen derivative ligands L1 and L2, have been achieved. The Eu(III) and Tb(III) lanthanide compounds have been found to display highly distinct and contrasting temperature-dependent dual emission and decay lifetimes, rendering them as potential sensitive temperature probes. The emission colors of the new lanthanide complexes can be tuned by controlling the ratio of the Eu(III) and Tb(III) complexes in a binary composite and the temperature. Bright white light emission based on the new binary Eu(III) and Tb(III) complexes has been achieved. Furthermore, the triarylborane functionality of the new complexes enables their use as effective probes for anions such as fluoride ions, allowing the further tuning of the lanthanide emission.
- Published
- 2016
33. LC-MS guided isolation of diterpenoids from Sapium insigne with α-glucosidase inhibitory activities
- Author
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Xiao-Yan Huang, Zhen Gao, Tong-Hua Yang, Hua Peng, Yan Dexiu, Xue-Mei Zhang, Chang-An Geng, Ji-Jun Chen, Yun-Bao Ma, and Tian-Ze Li
- Subjects
Stereochemistry ,Tandem mass spectrometry ,Sapium ,01 natural sciences ,Structure-Activity Relationship ,Non-competitive inhibition ,Liquid chromatography–mass spectrometry ,Tandem Mass Spectrometry ,Drug Discovery ,Structure–activity relationship ,Glycoside Hydrolase Inhibitors ,IC50 ,Pharmacology ,biology ,Molecular Structure ,Plant Stems ,010405 organic chemistry ,Chemistry ,alpha-Glucosidases ,General Medicine ,biology.organism_classification ,In vitro ,0104 chemical sciences ,010404 medicinal & biomolecular chemistry ,Diterpenes ,Two-dimensional nuclear magnetic resonance spectroscopy ,Chromatography, Liquid - Abstract
Ten new (1-10) and ten known (11-20) diterpenoids involving ent-atisane, ent-seco-atisane, ent-kaurane and ent-seco-kaurane types were isolated from Sapium insigne under the guidance of LCMS-IT-TOF analyses. Their structures were characterized by extensive spectroscopic analyses (HRESIMS, UV, IR, 1D and 2D NMR). A putative biosynthetic pathway was proposed for ent-seco-atisane diterpenoids. Their inhibitory activities on α-glucosidase in vitro were tested for the first time. Compound 4 showed moderate inhibitory effect on α-glucosidase with an IC50 value of 0.34 mM via a noncompetitive inhibition mechanism (Ki = 0.27 mM). The preliminary structure-activity relationships of the ent-atisane diterpenoids inhibiting α-glucosidase were discussed.
- Published
- 2018
34. The New Study Based on a Dual Ion Implantation PSD Structure
- Author
-
Tian Ze Li, Qian Li, and Xiang Peng Chen
- Subjects
Materials science ,Silicon ,business.industry ,Annealing (metallurgy) ,Detector ,Doping ,General Engineering ,Analytical chemistry ,chemistry.chemical_element ,Ion ,Semiconductor ,Ion implantation ,chemistry ,business ,Boron - Abstract
In the analysis of semiconductor position sensitive detector (PSD) based on the traditional structure, using dual ion implantation method to studying the new type of PSD structure. The new structure of the n-type silicon substrate by implanting a high dose, low energy boron ions and another high energy boron ion, Which subsequent annealing of 2h at 1050 °C in an ambient of dry O2to form a shallow and a low doped p-n junction. Experimental results show that the new structure of PSD can obtained high position resolution, smaller errors and nonlinear response time.
- Published
- 2015
35. New phenolic glycosides from Curculigo orchioides and their xanthine oxidase inhibitory activities
- Author
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Tian-Ze Li, Zhen-Tao Deng, Xue-Mei Zhang, Xing-Long Chen, Chang-An Geng, Ji-Jun Chen, Xiao-Yan Huang, and Ai-Xue Zuo
- Subjects
Xanthine Oxidase ,Stereochemistry ,01 natural sciences ,chemistry.chemical_compound ,Curculigo ,Phenols ,Drug Discovery ,Ic50 values ,Organic chemistry ,Glycosides ,Enzyme Inhibitors ,Xanthine oxidase ,Pharmacology ,chemistry.chemical_classification ,biology ,Molecular Structure ,010405 organic chemistry ,Chemistry ,Glycoside ,General Medicine ,Uricosuric Agents ,biology.organism_classification ,0104 chemical sciences ,Rhizome ,Curculigo orchioides ,010404 medicinal & biomolecular chemistry ,Two-dimensional nuclear magnetic resonance spectroscopy - Abstract
Seven new phenolic glycosides including two heterocyclic phenolic derivatives orcinosides I-J (1-2) and five chlorophenolic glycosides curculigines J-N (3-7), together with nineteen known compounds were isolated from the rhizome of Curculigo orchioides. Based on extensive spectroscopic analyses (UV, IR, HRESIMS, 1D and 2D NMR), the structures of the new compounds were identified. Orcinoside I (1) and J (2) displayed xanthine oxidase inhibitory activities with IC50 values 0.25 and 0.62mM respectively.
- Published
- 2017
36. Study on the Properties of Melamine Cyanurate Modified Polyamide 6 Nanocomposites with Different Dimensional Siliciferous Particles
- Author
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Li Li Li, Bin Sun, Tian Ze Wu, Meifang Zhu, Shou Yang Lu, Zhi Hao Wu, and Shuai Shuai Jiang
- Subjects
Universal testing machine ,Nanocomposite ,Materials science ,Mechanical Engineering ,engineering.material ,Condensed Matter Physics ,Halloysite ,Limiting oxygen index ,chemistry.chemical_compound ,Montmorillonite ,chemistry ,Mechanics of Materials ,Polyamide ,Ultimate tensile strength ,Melamine cyanurate ,engineering ,General Materials Science ,Composite material - Abstract
Different dimensional siliciferous particles including silica (0D), halloysite nanotubes (HNTs,1D) and montmorillonite (MMT,2D) were melt blending with certain amount of melamine cyanurate and polyamide 6(PA6) by a twin-screw extruder. Characterization of the PA6 composites has been investigated using scan electron microscopy (SEM), thermal gravimetric analyzer (TGA), universal testing machine and limiting oxygen index instrument. SEM images indicate that the nanoparticles were uniformly dispersed in the PA6 but there was some aggregation of MCA in the composites. The incorporation of silica exerted a negative effect on the flame retardancy of PA6/MCA composite, whereas adding HNTs and MMT lead to the improvements of LOI value of 30.4 and 30.9 respectively. TGA results show that PA6/MCA/silica, PA6/MCA/HNTs and PA6/MCA/OMMT exhibit two degradation stages. Higher Tmax1 and Tmax2 appeared comparing with PA6/MCA. Char residue of PA6/MCA/OMMT at 600°C were elevated most. HNTs and OMMT can increase the tensile strength and elongation of PA6/MCA by universal testing machine results, even higher than pure PA6, showing enhanced effects of these 1D and 2D fillers. These could enhance strength of the char and finally increase the flame retardancy of PA6.
- Published
- 2014
37. Synthesis and Cytotoxicity Evaluation of Tropinone Derivatives
- Author
-
Tian-Ze Li, Ji-Jun Chen, Chang-An Geng, Chang-Li Sun, Xing-Long Chen, Tong-Hua Yang, Xue-Mei Zhang, Xiu-Juan Yin, and Jun Zhou
- Subjects
0301 basic medicine ,Tropinone ,Stereochemistry ,Cytotoxicity ,Pharmacology toxicology ,MTS ,Plant Science ,Toxicology ,01 natural sciences ,Biochemistry ,Analytical Chemistry ,03 medical and health sciences ,chemistry.chemical_compound ,Derivative (finance) ,Ic50 values ,Bioorganic chemistry ,Pharmacology ,010405 organic chemistry ,Claisen-Schmidt reaction ,Organic Chemistry ,0104 chemical sciences ,030104 developmental biology ,chemistry ,Plant biochemistry ,Original Article ,Human cancer ,Food Science - Abstract
Sixteen tropinone derivatives were prepared, and their antitumor activities against five human cancer cells (HL-60, A-549, SMMC-7721, MCF-7 and SW480) were evaluated with MTS [3-(4,5-dimethylthiazol-2-yl)-5-(3-carboxy methoxyphenyl)-2-(4-sulfopheny)-2H-tetrazolium] assay. Most of the derivatives exhibited better activities compared with tropinone at the concentration of 40 μM. Particularly, derivative 6 showed significant activities with IC50 values of 3.39, 13.59, 6.65, 13.09 and 12.38 μM respectively against HL-60, A-549, SMMC-7721, MCF-7 and SW480 cells, which suggested more potent activities than that of cis-dichlorodiamineplatinum (DDP). Graphical Abstract
- Published
- 2016
38. ChemInform Abstract: Enantioselective Direct Vinylogous Aldol-Cyclization Cascade Reaction Between β,γ-Unsaturated Amides and o-Quinones
- Author
-
Feng Sha, Xin-Yan Wu, Jun-Hao Fu, Tian-Ze Li, and Yu Jiang
- Subjects
Cascade reaction ,Aldol reaction ,Chemistry ,Organocatalysis ,Enantioselective synthesis ,Organic chemistry ,General Medicine ,O quinones - Abstract
The method offers a highly enantioselective access to novel spirocyclic dihydropyranone derivatives.
- Published
- 2016
39. First total synthesis of rhuscholide A, glabralide B and denudalide
- Author
-
Chang-An Geng, Tian-Ze Li, and Ji-Jun Chen
- Subjects
chemistry.chemical_classification ,010405 organic chemistry ,Organic Chemistry ,Total synthesis ,010402 general chemistry ,01 natural sciences ,Biochemistry ,0104 chemical sciences ,chemistry.chemical_compound ,chemistry ,Yield (chemistry) ,Drug Discovery ,Organic chemistry ,Phenol ,Aldol condensation ,Piperidine ,Benzofuran ,Lactone - Abstract
The first total synthesis of rhuscholide A, a benzofuran lactone possessing anti-HIV-1 activity, had been accomplished in 14 linear steps with 10.6% overall yield. In this synthesis, base-mediated phenol ortho-alkylation and piperidine promoted aldol condensation were exploited as key steps. The synthesis was flexible and allowed for the convenient preparation of two analogous natural products glabralide B and denudalide.
- Published
- 2019
40. Catalytic enantioselective addition of alcohols to isatin-derived N-Boc ketimines
- Author
-
Xi-Bo Wang, Xin-Yan Wu, Tian-Ze Li, and Feng Sha
- Subjects
chemistry.chemical_compound ,Chemistry ,Isatin ,Organic Chemistry ,Drug Discovery ,Enantioselective synthesis ,Organic chemistry ,Biochemistry ,Catalysis ,Bifunctional catalyst - Abstract
The enantioselective addition of alcohols to isatin-derived N -Boc ketimines was investigated for the first time. Isatin-derived N , O -aminals were obtained in excellent yields with moderate-to-good enantioselectivities (up to 78% ee) in the presence of a quinine-based bifunctional catalyst.
- Published
- 2013
41. Preparation of Vitamin C Dripping Pill and its Quality Evaluation
- Author
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Xiao Lin Xu, Kehai Liu, Tian Ze Bian, and Qing Zhu
- Subjects
Matrix (chemical analysis) ,Chromatography ,Vitamin C ,Matrix type ,Chemistry ,Pill ,PEG ratio ,General Engineering ,Analytical chemistry ,Dispersion (chemistry) ,Dosage form ,Uv spectrophotometry - Abstract
[Objective] to study the modeling technique of Vitamin C dripping pill and its quality evaluation. [Method] the preparation conditions were optimized by orthogonal experiments using encapsulation efficiency (EE) as the target index. The matrix type (PEG 4000:PEG 6000), ratio of drug to matrix, dripping temperature and dripping distance with three levels were chosen in the orthogonal experiments. Weight variation, dispersion limit, content and stability of the dripping pill under the optimum conditions were estimated. [Results] The optimum conditions were obtained when matrix type (PEG 4000: PEG 6000), ratio of drug to matrix, dripping temperature and dripping distance were 6:1, 1:7, 80 °C and 20 cm respectively. The weight variation and dispersion limit of the dripping pill ranged in -13.47-13.38% and 4.5-5.0min. An assay method was developed by UV spectrophotometry. Its quality was stable during the three months of accelerated test. [Conclusion] the weight variation and dispersion limit of the dripping pill with good morphology and high stability came up to the requirements of Ch. P, the assay method was simple and accurate, demonstrating that the dripping pill can be used as edible or pharmaceutical dosage form.
- Published
- 2012
42. Enantioselective direct vinylogous aldol-cyclization cascade reaction between β,γ-unsaturated amides and o-quinones
- Author
-
Feng Sha, Tian-Ze Li, Jun-Hao Fu, Xin-Yan Wu, and Yu Jiang
- Subjects
010405 organic chemistry ,Chemistry ,Stereochemistry ,Organic Chemistry ,Enantioselective synthesis ,010402 general chemistry ,O quinones ,01 natural sciences ,Biochemistry ,0104 chemical sciences ,Cascade reaction ,Aldol reaction ,Yield (chemistry) ,Electrophile ,Physical and Theoretical Chemistry - Abstract
1,2-Diketones are employed, for the first time, as electrophiles in the vinylogous aldol reaction. With 5 mol% of chiral tertiary amine-thiourea C8, a direct vinylogous aldol-cyclization cascade reaction between β,γ-unsaturated amides and o-quinones has been achieved to produce spirocyclic dihydropyranones in 76–99% yield and 82–95% ee.
- Published
- 2016
43. ChemInform Abstract: Enantioselective Vinylogous Michael/Cyclization Cascade Reaction of Acyclic β,γ-Unsaturated Amides with Isatylidene Malononitriles: Asymmetric Construction of Spirocyclic Oxindoles
- Author
-
Yu Jiang, Tian-Ze Li, Xin-Yan Wu, Jin Xie, and Feng Sha
- Subjects
Cascade reaction ,Stereochemistry ,Chemistry ,Organocatalysis ,Enantioselective synthesis ,General Medicine - Published
- 2016
44. Simulation of Silicon Solar Cell Using PC1D
- Author
-
Tian Ze Li, Luan Hou, Chuan Jiang, and Xia Zhang
- Subjects
Materials science ,Silicon ,business.industry ,Band gap ,Photovoltaic system ,General Engineering ,chemistry.chemical_element ,Engineering physics ,Crystalline semiconductor ,Software ,chemistry ,Electronic engineering ,Solar simulator ,business ,Silicon solar cell - Abstract
PC1D software, which was developed by the University of New South Wales, has been used to simulate photovoltaic properties of crystalline semiconductor devices. The paper focuses on the simulation of silicon solar cell by PC1D. The simulation of silicon solar cell is carried out by setting up key parameters, which include device area, thickness, band gap, etc. Several important characteristics of silicon solar cells are obtained by simulation.
- Published
- 2011
45. Basic fibroblast growth factor increases intracellular magnesium concentration through the specific signaling pathways
- Author
-
Han-Na Kim, Bing-Zhe Hong, Sun-Ah Park, Tian-Ze Ma, Yong-Geun Kwak, Hwan-Gyu Kim, Han-Gyu Kim, and Hyung-Sub Kang
- Subjects
inorganic chemicals ,Pyridines ,Morpholines ,Basic fibroblast growth factor ,Intracellular Space ,Mitogen-activated protein kinase kinase ,Receptor tyrosine kinase ,Cell Line ,Wortmannin ,Phosphatidylinositol 3-Kinases ,chemistry.chemical_compound ,Humans ,Magnesium ,Estrenes ,Protein Kinase Inhibitors ,Molecular Biology ,Phosphoinositide-3 Kinase Inhibitors ,Flavonoids ,Dose-Response Relationship, Drug ,biology ,MAP kinase kinase kinase ,Phospholipase C gamma ,Akt/PKB signaling pathway ,Imidazoles ,Endothelial Cells ,Cell Biology ,General Medicine ,Protein-Tyrosine Kinases ,Tyrphostins ,Genistein ,Pyrrolidinones ,Cell biology ,Androstadienes ,Microscopy, Fluorescence ,chemistry ,Chromones ,cardiovascular system ,biology.protein ,Fibroblast Growth Factor 2 ,Tyrosine kinase ,Platelet-derived growth factor receptor ,Signal Transduction - Abstract
Basic fibroblast growth factor (bFGF) plays an important role in angiogenesis. However, the underlying mechanisms are not clear. Mg(2+) is the most abundant intracellular divalent cation in the body and plays critical roles in many cell functions. We investigated the effect of bFGF on the intracellular Mg(2+) concentration ([Mg(2+)](i)) in human umbilical vein endothelial cells (HUVECs). bFGF increased [Mg(2+)](i) in a dose-dependent manner, independent of extracellular Mg(2+). This bFGF-induced [Mg(2+)](i) increase was blocked by tyrosine kinase inhibitors (tyrphostin A-23 and genistein), phosphatidylinositol 3-kinase (PI3K) inhibitors (wortmannin and LY294002) and a phospholipase Cgamma (PLCgamma) inhibitor (U73122). In contrast, mitogen-activated protein kinase inhibitors (SB202190 and PD98059) did not affect the bFGF-induced [Mg(2+)](i) increase. These results suggest that bFGF increases the [Mg(2+)](i) from the intracellular Mg(2+) stores through the tyrosine kinase/PI3K/PLCgamma-dependent signaling pathways.
- Published
- 2009
46. ChemInform Abstract: Enantioselective Aza-Morita-Baylis-Hillman Reaction Between Acrylates and N-Boc Isatin Ketimines: Asymmetric Construction of Chiral 3-Substituted-3-aminooxindoles
- Author
-
Feng Sha, Jing-Ying Qian, Xuan Zhao, Xin-Yan Wu, and Tian-Ze Li
- Subjects
chemistry.chemical_compound ,chemistry ,Organocatalysis ,Isatin ,Enantioselective synthesis ,Organic chemistry ,Baylis–Hillman reaction ,General Medicine - Abstract
The first enantioselective aza-Morita—Baylis—Hillman reaction of acrylates with ketimines derived from isatins is developed.
- Published
- 2015
47. ChemInform Abstract: Direct Enantioselective Vinylogous Aldol-Cyclization Cascade Reaction of Allyl Pyrazoleamides with Isatins: Asymmetric Construction of Spirocyclic Oxindole-Dihydropyranones
- Author
-
Feng Sha, Tian-Ze Li, Yu Jiang, Xin-Yan Wu, and Yu-Qing Guan
- Subjects
chemistry.chemical_compound ,chemistry ,Aldol reaction ,Cascade reaction ,Organocatalysis ,Enantioselective synthesis ,Organic chemistry ,Oxindole ,General Medicine ,Optically active ,Catalysis - Abstract
The first enantioselective vinylogous aldol–cyclization cascade reaction of allyl pyrazoleamides with isatins is reported. With 1 mol% of Takemoto catalyst, optically active spirocyclic oxindole–dihydropyranones were obtained in excellent yields (93–99%) and good-to-excellent enantioselectivities (82–97% ee).
- Published
- 2015
48. Torilin fromTorilis japonica (Houtt.) DC. Blocks hKv1.5 channel current
- Author
-
Dong-Jin Yoo, Hoon Park, Jae Soon Eun, Dae Keun Kim, Young Hoon Jung, Sun-Ah Park, Yong Geun Kwak, and Tian-Ze Ma
- Subjects
Patch-Clamp Techniques ,Torilis japonica ,Inactivation kinetics ,Transfection ,Cell Line ,Membrane Potentials ,Kv1.5 Potassium Channel ,Mice ,Sesquiterpenes, Guaiane ,Drug Discovery ,Potassium Channel Blockers ,Animals ,Humans ,Atrial myocytes ,Dose-Response Relationship, Drug ,Molecular Structure ,biology ,Plant Extracts ,Chemistry ,Organic Chemistry ,Human heart ,biology.organism_classification ,Deactivation kinetics ,DC block ,Delayed rectifier ,Fruit ,Chromatography, Gel ,Biophysics ,Molecular Medicine ,Current (fluid) ,Apiaceae - Abstract
Torilin was purified from Torilis japonica (Houtt.) DC., and its effects on a rapidly activating delayed rectifier K+ channel (hKv1.5), cloned from human heart and stably expressed in Ltk- cells, as well as the corresponding K+ current (the ultrarapid delayed rectifier, I(KUR)) were assessed in human atrial myocytes. Using the whole cell configuration of the patch-clamp technique, torilin was found to inhibit the hKv1.5 current in time and voltage-dependent manners, with an IC50 value of 2.51+/-0.34 microM at +60 mV. Torilin accelerated the inactivation kinetics of the hKv1.5 channel, and slowed the deactivation kinetics of the hKv1.5 current, resulting in a tail crossover phenomenon. Additionally, torilin inhibited the hKv1.5 current in a use-dependent manner. These results strongly suggest that torilin is a type of open-channel blocker of the hKv1.5 channel.
- Published
- 2006
49. ChemInform Abstract: Organocatalyzed Enantioselective Mannich Reaction of Pyrazoleamides with Isatin-Derived Ketimines
- Author
-
Xi-Bo Wang, Tian-Ze Li, Feng Sha, and Xin-Yan Wu
- Subjects
Coupling (electronics) ,chemistry.chemical_compound ,chemistry ,Isatin ,Enantioselective synthesis ,General Medicine ,Mannich reaction ,Combinatorial chemistry - Abstract
The first organocatalytic Mannich coupling of pyrazoleamides with ketimines of type (I)/(VI) is reported.
- Published
- 2014
50. ChemInform Abstract: Enantioselective Squaramide-Catalyzed Domino Mannich-Cyclization Reaction of Isatin Imines
- Author
-
Xi-Bo Wang, Tian-Ze Li, Xin-Yan Wu, and Feng Sha
- Subjects
chemistry.chemical_compound ,chemistry ,Organocatalysis ,Isatin ,Squaramide ,Enantioselective synthesis ,General Medicine ,Bifunctional ,Combinatorial chemistry ,Domino ,Catalysis - Abstract
A efficient procedure using a bifunctional squaramide catalyst is presented for the domino Mannich cyclization of isatin imines and 1,3-dicarbonyl compounds (II) and (IV) to produce 3-amino-2-oxindoles in high yields and excellent stereoselectivities.
- Published
- 2014
Catalog
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