17 results on '"Yi-Hong Zou"'
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2. Using quantum chemistry theory to elucidate the mechanism for treating sulfonamide antibiotic wastewater by progressive freezing
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Yan, Zhang, Tong-shuai, Liu, Xiao-zhuang, Wang, Yu-can, Liu, Chen, Zhao, Hao, Lin, and Yi-hong, Zou
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- 2023
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3. Salviplenoid A from Salvia plebeia attenuates acute lung inflammation via modulating <scp>NF‐κB</scp> and Nrf2 signaling pathways
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Yi-Hong Zou, Run-Zhu Fan, Jia-Luo Huang, Sheng Yin, Lei Zhang, and Gui-Hua Tang
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NF-E2-Related Factor 2 ,Acute Lung Injury ,Anti-Inflammatory Agents ,Inflammation ,Lung injury ,Pharmacology ,Proinflammatory cytokine ,Mice ,03 medical and health sciences ,chemistry.chemical_compound ,0302 clinical medicine ,In vivo ,medicine ,Animals ,Humans ,Secretion ,Salvia ,0303 health sciences ,Lung ,biology ,business.industry ,030302 biochemistry & molecular biology ,NF-kappa B ,NF-κB ,respiratory system ,biology.organism_classification ,Disease Models, Animal ,RAW 264.7 Cells ,medicine.anatomical_structure ,chemistry ,030220 oncology & carcinogenesis ,medicine.symptom ,Salvia plebeia ,business ,Drugs, Chinese Herbal ,Signal Transduction - Abstract
Acute lung injury (ALI) involves series of inflammatory pathologies and cause high morbidity. Salviplenoid A (SA) was a new sesquiterpenoid from the traditional inflammatory herb Salvia plebeia. In our previous study, SA exhibited antiinflammatory activity in RAW264.7 cells. However, the extensive effects of SA in human cells and in vivo and the active mechanisms are unclear. Thus, in this study, we sought to access its effects in vitro and in vivo and to investigate its mechanisms. SA was proved to inhibit the induction of proinflammatory cytokines in human cell types, including pulmonary epithelial cells and endothetial cells. It also depressed monocyte adhesion. Moreover, SA potently attenuated the acute lung inflammation in the LPS-induced mouse model shown by down-regulation of proinflammatory mediators, inhibition of polymorphonuclear neutrophil infiltration, and alleviation of related symptoms like alveolar congestion and mucus secretion. Further evaluation confirmed that SA regulated NF-κB pathway by inhibiting the IκB-α phosphorylation. And it markedly mediated Nrf2/HO-1 pathway by activating the Nrf2/HO-1 expression and promoting Nrf2 nuclear translocation. Therefore, SA could attenuate acute lung inflammation via suppressing NF-κB and activating Nrf2, which provide a theoretical basis for the potential application of SA in clinic.
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- 2020
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4. (+)‐Isobicyclogermacrenal and spathulenol from Aristolochia yunnanensis alleviate cardiac fibrosis by inhibiting transforming growth factor β /small mother against decapentaplegic signaling pathway
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Wei Li, Sheng Yin, Han-Zhuang Weng, Lin Chen, Gui-Hua Tang, Lan-Lan Lou, Xianzhang Bu, Binhua Zhou, and Yi-Hong Zou
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Male ,Cardiac fibrosis ,Mothers ,SMAD ,Pharmacology ,Rats, Sprague-Dawley ,Mice ,03 medical and health sciences ,chemistry.chemical_compound ,0302 clinical medicine ,Transforming Growth Factor beta ,Fibrosis ,medicine ,Animals ,Humans ,Medicine, Chinese Traditional ,Aldehydes ,0303 health sciences ,030302 biochemistry & molecular biology ,Aristolochia ,medicine.disease ,Oxymatrine ,chemistry ,Decapentaplegic signaling pathway ,030220 oncology & carcinogenesis ,Myocardial fibrosis ,Signal transduction ,Sesquiterpenes ,Signal Transduction ,Transforming growth factor - Abstract
Cardiac fibrosis contributes to both systolic and diastolic dysfunction in many cardiac pathophysiologic conditions. Antifibrotic therapies are likely to be a crucial strategy in curbing many fibrosis-related cardiac diseases. In our previous study, an ethyl acetate extract of a traditional Chinese medicine Aristolochia yunnanensis Franch. was found to have a therapeutic effect on myocardial fibrosis in vitro and in vivo. However, the exact chemicals and their mechanisms responsible for the activity of the crude extract have not been illustrated yet. In the current study, 10 sesquiterpenoids (1-10) were isolated from the active extract, and their antifibrotic effects were systematically evaluated in transforming growth factor β 1 (TGFβ1)-stimulated cardiac fibroblasts and NIH3T3 fibrosis models. (+)-Isobicyclogermacrenal (1) and spathulenol (2) were identified as the main active components, being more potent than the well-known natural antifibrotic agent oxymatrine. Compounds 1 and 2 could inhibit the TGFβ1-induced cardiac fibroblasts proliferation and suppress the expression of the fibrosis biomarkers fibronectin and α-smooth muscle actin via down-regulation of their mRNA levels. The mechanism study revealed that 1 and 2 could inhibit the phosphorylation of TGFβ type I receptor, leading to the decrease of the phosphorylation levels of downstream Smad2/3, then consequently blocking the nuclear translocation of Smad2/3 in the TGFβ/Smad signaling pathway. These findings suggest that 1 and 2 may serve as promising natural leads for the development of anticardiac fibrosis drugs.
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- 2018
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5. Anti-inflammatory sesquiterpenoids from the Traditional Chinese Medicine Salvia plebeia : Regulates pro-inflammatory mediators through inhibition of NF-κB and Erk1/2 signaling pathways in LPS-induced Raw264.7 cells
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Wei Li, Abrar Ahmed, Liang Zhao, Xin Liu, Jing-Mei Bao, Yi-Hong Zou, You-Kai Xu, Sheng Yin, Jun-Sheng Zhang, and Gui-Hua Tang
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Lipopolysaccharides ,0301 basic medicine ,MAP Kinase Signaling System ,medicine.drug_class ,medicine.medical_treatment ,Anti-Inflammatory Agents ,Pharmacology ,Biology ,Anti-inflammatory ,Mice ,03 medical and health sciences ,chemistry.chemical_compound ,0302 clinical medicine ,Drug Discovery ,medicine ,Animals ,Salvia ,Medicine, Chinese Traditional ,Chromatography, High Pressure Liquid ,Inflammation ,Plant Extracts ,Tumor Necrosis Factor-alpha ,Macrophages ,NF-kappa B ,NF-κB ,Plant Components, Aerial ,biology.organism_classification ,Blot ,Disease Models, Animal ,RAW 264.7 Cells ,030104 developmental biology ,Cytokine ,chemistry ,Plebeia ,030220 oncology & carcinogenesis ,Cytokines ,Phosphorylation ,I-kappa B Proteins ,Inflammation Mediators ,Signal transduction ,Salvia plebeia ,Sesquiterpenes ,Signal Transduction - Abstract
Ethnopharmacological relevance Salvia plebeia R. Brown, a traditional Chinese medicinal herb, has been used to treat inflammatory diseases such as cough, hepatitis, and diarrhea for a long history. Aim of the study The aim of the present study was to isolate and identify potential anti-inflammatory agents from the herb of S. plebeia, which may have contributed to its folk pharmacological use in the treatment of inflammatory diseases. Material and methods The aerial parts of S. plebeia were extracted with 95% ethanol and separated by silica gel, RP-C18, Sephadex LH-20, and HPLC. The structures of the isolated compounds were elucidated by extensive spectroscopic analysis (MS, NMR, and X-ray). Anti-inflammatory activities of all compounds were evaluated by the model of LPS-induced up-regulated of NO in Raw264.7 macrophages. The expression levels of cytokine (TNF-α) and proteins (iNOS and COX-2) were assessed by ELISA kit and Western blotting analysis, respectively. Furthermore, the influences of salviplenoid A (1) on NF-κB and MAPK signaling pathways were determined by Western blotting analysis and immunofluorescence assay. Results Six new (1−6, salviplenoids A–F) and ten known (7–16) sesquiterpenoids were isolated from the herb of S. plebeia. The absolute configurations of compounds 1, 2, and 7 were determined by X-ray diffraction. The new eudesmane-type sesquiterpenoid, salviplenoid A (1), significantly decreased the release of NO and TNF-α and the expression of proteins iNOS and COX-2. In addition, the biochemical mechanistic study indicated that 1 regulated the NF-κB dependent transcriptional activity through inhibiting the nuclear translocation of p50/p65 dimer and decreasing the phosphorylation of IκB and Erk1/2. Conclusions Among all sesquiterpenoids isolated from S. plebeian, the new salviplenoid A (1) exhibited the most potent anti-inflammatory activity in LPS-induced Raw264.7 cells via inhibition of NF-κB and Erk1/2 signaling pathways.
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- 2018
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6. Effects of LiNbO3-doping on properties of (Na0.535K0.48)NbO3 piezoelectric ceramics with high electromechanical coupling coefficient for application in surface acoustic wave devices
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Cheng Shong Hong, Sheng-Yuan Chu, Jian Fu Tang, Yi Hong Zou, Jyh Sheen, Chung Ming Weng, and Cheng Che Tsai
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010302 applied physics ,Electromechanical coupling coefficient ,Materials science ,Process Chemistry and Technology ,Surface acoustic wave ,Doping ,Sintering ,02 engineering and technology ,021001 nanoscience & nanotechnology ,Microstructure ,01 natural sciences ,Piezoelectricity ,Surfaces, Coatings and Films ,Electronic, Optical and Magnetic Materials ,visual_art ,0103 physical sciences ,Materials Chemistry ,Ceramics and Composites ,visual_art.visual_art_medium ,Relative density ,Ceramic ,Composite material ,0210 nano-technology - Abstract
In this study, lead-free LiNbO3-doped (Na0.535K0.48)NbO3 (NKN) ceramics (NKLxN, x = 0–0.09) were prepared using a conventional mixed oxide method to investigate the effects of LiNbO3 additives on the microstructure and electrical properties. The addition of LiNbO3 reduced the optimal sintering temperature from 1100 to 950 ℃ and increased the bulk relative density to 99.61% (g/cm3) at x = 0.05 through the formation of a homogeneous microstructure. The electrical properties remained highly stable, even when the ambient temperature was increased from room temperature to 140 ℃. NKLxN ceramics sintered at 950 ℃ with x = 0.05 exhibited the following excellent piezoelectric properties: kp:50% (34%); kt:53% (40%); Qm:168 (112); d33:150 pC/N (80 pC/N); and tan δ :4% (8%). These values far exceed those of pure NKN ceramics sintered at 1100 ℃. Surface acoustic wave (SAW) devices fabricated using the proposed NKLxN (x = 0.05) ceramics presented high phase velocity of 3210 m/s, k2 of 6.7%, and TCF of approximately −282 ppm/℃. Our results clearly demonstrate the effectiveness of adding LiNbO3 to prevent deliquescence and thereby enhance resistance to the effects of humidity. The resulting devices are highly sensitive to changes in temperature, making them ideally suited to electromechanical transducers as well as SAW temperature sensors.
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- 2017
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7. Novel degraded polycyclic polyprenylated acylphloroglucinol and new polyprenylated benzophenone from Hypericum sampsonii
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Sheng Yin, Gui-Hua Tang, Jun-Sheng Zhang, Jia-Luo Huang, Abrar Ahmed, Xin Liu, and Yi-Hong Zou
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010405 organic chemistry ,Stereochemistry ,Phloroglucinol ,Hypericum sampsonii ,Plant Science ,010402 general chemistry ,Ring (chemistry) ,01 natural sciences ,Biochemistry ,0104 chemical sciences ,chemistry.chemical_compound ,chemistry ,Cyclohexenone ,Benzophenone ,Organic chemistry ,Agronomy and Crop Science ,Derivative (chemistry) ,Biotechnology - Abstract
Norhypersampsone A ( 1 ), a novel degraded polycyclic polyprenylated acylphloroglucinol (PPAP) derivative, 3-(2-hydroxy-7-methyl-3-methyleneoct-6-enyl)-5-isoprenyl-2,4,6-trihydroxybenzophenone ( 2 ), a new polyprenylated benzophenone derivative, and nine known compounds ( 3 – 11 ) were isolated from Hypericum sampsonii . Their structures were elucidated by comprehensive spectroscopic techniques. Compound 1 represents a novel cyclohexenone monocyclic-PPAP formed by losing the fragment of C-2–C-4 and the side chains at C-3 and C-5 in the phloroglucinol ring. The results of the inhibitory effects of compounds 1 – 11 on the nitric oxide (NO) production induced by lipopolysaccharide (LPS) in RAW 264.7 macrophages showed that compounds 1 , 6 – 8 , and 10 exhibited weak activities with IC 50 values in the range of 20.3–37.1 μM.
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- 2017
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8. Three new diterpenoids from Marrubium aschersonii
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Yi-Hong Zou, Ye Chen, Jing-Mei Bao, Jun-Sheng Zhang, Jing-Jun Zhao, and Gui-Hua Tang
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biology ,010405 organic chemistry ,Chemistry ,Stereochemistry ,Marrubenol ,Plant Science ,biology.organism_classification ,01 natural sciences ,Biochemistry ,Terpenoid ,0104 chemical sciences ,Nitric oxide ,Labdane ,010404 medicinal & biomolecular chemistry ,chemistry.chemical_compound ,Lamiaceae ,Agronomy and Crop Science ,Marrubium ,Biotechnology - Abstract
One new halimane diterpenoid, marrubasch C (1), two new labdane diterpenoids, marrubaschs D and E (2 and 3), and three known labdane diterpenoids, marrubasch F (4), marrubiin (5), and marrubenol (6), were isolated from the ethanol extract of Marrubium aschersonii Magnus (Lamiaceae). Structures of these compounds were elucidated on the basis of spectroscopic analysis. The inhibitory effects of compounds 1–6 on nitric oxide (NO) production in RAW 264.7 macrophage cells activated by lipopolysaccharide (LPS) were investigated and all the compounds showed weak activity.
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- 2016
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9. Polycyclic polyprenylated acylphloroglucinols: natural phosphodiesterase-4 inhibitors from Hypericum sampsonii
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Sheng Yin, Yi-Hong Zou, Zhen-Zhen Li, Gui-Hua Tang, Jun-Sheng Zhang, and Yan-Qiong Guo
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Bicyclic molecule ,010405 organic chemistry ,Stereochemistry ,General Chemical Engineering ,Substrate (chemistry) ,General Chemistry ,010402 general chemistry ,Ring (chemistry) ,01 natural sciences ,Adenosine ,0104 chemical sciences ,chemistry.chemical_compound ,chemistry ,medicine ,Nonane ,Undecane ,IC50 ,Rolipram ,medicine.drug - Abstract
Chemical investigation of the aerial parts of Hypericum sampsonii led to the isolation of seven new polycyclic polyprenylated acylphloroglucinols, hypersampsonones A–G (1–7), together with 23 known analogs (8–30). Their structures including the absolute configurations were elucidated by combined spectroscopic analysis, quantum chemical ECD calculations, and chemical methods. Compound 1 represents an unprecedented cyclocitral monoterpene-coupled bicyclo[3.3.1]nonane skeleton, while 2 features an unusual hexahydrofuro[2,3-b]furan-diepoxy ring system fused in a tricyclo[4.3.1.15,7]undecane skeleton. All the compounds were screened by using tritium-labeled adenosine 3′,5′-cyclic monophosphate ([3H]-cAMP) as substrate for their inhibitory activity against phosphodiesterase-4 (PDE4), which is a drug target for the treatment of asthma and chronic obstructive pulmonary disease. Compounds 1, 18–19, 21, and 25–30 exhibited inhibition with IC50 values less than 10 μM, in which compound 19 represented the most active compound (IC50 = 0.64 μM), being comparable to the positive control, rolipram (IC50 = 0.62 μM).
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- 2016
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10. Biscembranoids and Cembranoids from the Soft Coral Sarcophyton elegans
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Gui-Hua Tang, Yi-Hong Zou, Yun-Shao Xu, Abrar Ahmed, Jun-Sheng Zhang, Man-Xi Ge, Lan-Lan Lou, Yunyun Chen, Sheng Yin, and Wei Li
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South china ,Stereochemistry ,Coral ,Pharmaceutical Science ,Biology ,Crystallography, X-Ray ,Nitric Oxide ,01 natural sciences ,Article ,cembranoids ,Cell Line ,Mice ,X-Ray Diffraction ,Drug Discovery ,Ic50 values ,Animals ,Pharmacology, Toxicology and Pharmaceutics (miscellaneous) ,Molecular Structure ,Sarcophyton elegans ,010405 organic chemistry ,biscembranoids ,NO inhibition ,Anthozoa ,Cycloaddition ,0104 chemical sciences ,Biosynthetic Pathways ,010404 medicinal & biomolecular chemistry ,Diterpenes - Abstract
Two novel biscembranoids, sarelengans A and B (1 and 2), five new cembranoids, sarelengans C-G (3-7), along with two known cembranoids (8 and 9) were isolated from the South China Sea soft coral Sarcophyton elegans. Their structures were determined by spectroscopic and chemical methods, and those of 1, 4, 5, and 6 were confirmed by single crystal X-ray diffraction. Compounds 1 and 2 represent the first example of biscembranoids featuring a trans-fused A/B-ring conjunction between the two cembranoid units. Their unique structures may shed light on an unusual biosynthetic pathway involving a cembranoid-∆⁸ rather than the normal cembranoid-∆¹ unit in the endo-Diels-Alder cycloaddition. Compounds 2 and 3 exhibited potential inhibitory effects on nitric oxide production in RAW 264.7 macrophages, with IC50 values being at 18.2 and 32.5 μM, respectively.
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- 2017
11. A new bisabolane sesquiterpenoid and a new abietane diterpenoid from Cephalotaxus sinensis
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Yi-Hong Zou, Wei Li, Pek-Ha Sam, Abrar Ahmed, Sheng Yin, Jun-Sheng Zhang, and Gui-Hua Tang
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Magnetic Resonance Spectroscopy ,Stereochemistry ,Phytochemicals ,Plant Science ,01 natural sciences ,Biochemistry ,Analytical Chemistry ,Cephalotaxus ,chemistry.chemical_compound ,Abietane ,Cephalotaxus sinensis ,biology ,Molecular Structure ,010405 organic chemistry ,Spectrum Analysis ,Organic Chemistry ,Nuclear magnetic resonance spectroscopy ,biology.organism_classification ,Terpenoid ,0104 chemical sciences ,010404 medicinal & biomolecular chemistry ,chemistry ,Phytochemical ,Abietanes ,Spectrum analysis ,Sesquiterpenes - Abstract
Phytochemical investigation of Cephalotaxus sinensis has led to the isolation of a new bisabolane sesquiterpenoid (1), a new abietane diterpenoid (2), and 13 known compounds (3–15). Their structures were elucidated by extensive spectroscopic analysis (MS, UV, IR, and NMR).
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- 2017
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12. A Novel Heterodimer from Crotalaria ferruginea
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Yi-Hong, Zou, Xin, Liu, Ye-Na, Liu, Gui-Hua, Tang, and Sheng, Yin
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Molecular Structure ,Plant Extracts ,Crotalaria ,Dimerization - Abstract
A new compound was isolated from the traditional Chinese folk herb Crotalaria ferruginea. The structure of the new compound was identified as (±)-crotaferruphenol (1) based on analyses of its spectroscopic data including NMR, MS, and specific rotation values. (±)-Crotaferruphenol was a novel heterodimer characteristic of a unique spiroketal moiety, which was produced by the condensation reaction of a chromanone and a 2-isopropenybenzofuran. (±)-Crotaferruphenol exhibited inhibitory activity (IC50 = 6.57 μM.) against phosphodiesterase-4 (PDE4), a drug target for the treatment of chronic obstructive pulmonary disease and asthma.
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- 2016
13. New Cembrane-Type Diterpenoids from the South China Sea Soft Coral Sarcophyton ehrenbergi
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Zhang-Hua Sun, Yi-Hong Zou, Sheng Yin, and Gui-Hua Tang
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Models, Molecular ,China ,South china ,Cell Survival ,Stereochemistry ,Proton Magnetic Resonance Spectroscopy ,Coral ,Molecular Conformation ,Ovarian cancer cell line ,Pharmaceutical Science ,01 natural sciences ,Article ,cembranoids ,Molecular conformation ,Analytical Chemistry ,lcsh:QD241-441 ,Paleontology ,lcsh:Organic chemistry ,Cell Line, Tumor ,Anthozoa ,Drug Discovery ,Animals ,Humans ,Carbon-13 Magnetic Resonance Spectroscopy ,Physical and Theoretical Chemistry ,Sarcophyton ehrenbergi ,marine natural product ,Cell survival ,biology ,010405 organic chemistry ,Chemistry ,Organic Chemistry ,biology.organism_classification ,Nmr data ,0104 chemical sciences ,010404 medicinal & biomolecular chemistry ,Chemistry (miscellaneous) ,Molecular Medicine ,Diterpenes - Abstract
Chemical investigation on the soft coral Sarcophyton ehrenbergi collected from the Xisha Islands of the South China Sea have led to the isolation of eight cembranoids including five new ones, sarcophytonoxides A–E (1–5). The structures of new cembranoids (1–5) were determined by spectroscopic analysis and comparison of the NMR data with those of related analogues. The cytotoxicities of compounds 1–8 against human ovarian cancer cell line A2780 were also evaluated.
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- 2016
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14. A Novel Heterodimer from Crotalaria ferruginea
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Xin Liu, Yi-Hong Zou, Ye-Na Liu, Gui-Hua Tang, and Sheng Yin
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Pharmacology ,010405 organic chemistry ,Stereochemistry ,Drug target ,Pulmonary disease ,Crotalaria ferruginea ,Plant Science ,General Medicine ,Condensation reaction ,01 natural sciences ,0104 chemical sciences ,010404 medicinal & biomolecular chemistry ,chemistry.chemical_compound ,Complementary and alternative medicine ,chemistry ,Drug Discovery ,Moiety ,Specific rotation ,IC50 - Abstract
A new compound was isolated from the traditional Chinese folk herb Crotalaria ferruginea. The structure of the new compound was identified as (±)-crotaferruphenol (1) based on analyses of its spectroscopic data including NMR, MS, and specific rotation values. (±)-Crotaferruphenol was a novel heterodimer characteristic of a unique spiroketal moiety, which was produced by the condensation reaction of a chromanone and a 2-isopropenybenzofuran. (±)-Crotaferruphenol exhibited inhibitory activity (IC50 = 6.57 μM.) against phosphodiesterase-4 (PDE4), a drug target for the treatment of chronic obstructive pulmonary disease and asthma.
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- 2016
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15. Tunable bi-functional photonic device based on one-dimensional photonic crystal infiltrated with a bistable liquid-crystal layer
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Jy Shan Hsu, Yu Ting Lin, Chong Yin Wu, Victor Ya. Zyryanov, Wei Lee, Ivan V. Timofeev, and Yi Hong Zou
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Materials science ,Bistability ,business.industry ,Homeotropic alignment ,Physics::Optics ,Optical switch ,Yablonovite ,Atomic and Molecular Physics, and Optics ,Condensed Matter::Soft Condensed Matter ,Optics ,Liquid crystal ,Optoelectronics ,Photonics ,business ,Refractive index ,Photonic crystal - Abstract
We investigated the optical properties of a one-dimensional photonic crystal infiltrated with a bistable chiral tilted homeotropic nematic liquid crystal as the central defect layer. By modulating the nematic director orientation with applied voltage, the electrical tunability of the defect modes was observed in the transmission spectrum. The composite not only is a general tunable device but also involves the green concept in that it can operate in two stable states at 0 V. Under the parallel-polarizer scheme, the spectral characteristics suggest a potential application for this device as an energy-efficient multichannel optical switch.
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- 2011
16. Biscembranoids and Cembranoids from the Soft Coral Sarcophyton elegans.
- Author
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Wei Li, Yi-Hong Zou, Man-Xi Ge, Lan-Lan Lou, Yun-Shao Xu, Ahmed, Abrar, Yun-Yun Chen, Jun-Sheng Zhang, Gui-Hua Tang, and Sheng Yin
- Abstract
Two novel biscembranoids, sarelengans A and B (1 and 2), five new cembranoids, sarelengans C–G (3–7), along with two known cembranoids (8 and 9) were isolated from the South China Sea soft coral Sarcophyton elegans. Their structures were determined by spectroscopic and chemical methods, and those of 1, 4, 5, and 6 were confirmed by single crystal X-ray diffraction. Compounds 1 and 2 represent the first example of biscembranoids featuring a trans-fused A/B-ring conjunction between the two cembranoid units. Their unique structures may shed light on an unusual biosynthetic pathway involving a cembranoid-Δ
8 rather than the normal cembranoid-Δ¹ unit in the endo-Diels-Alder cycloaddition. Compounds 2 and 3 exhibited potential inhibitory effects on nitric oxide production in RAW264.7 macrophages, with IC50 values being at 18.2 and 32.5 μM, respectively. [ABSTRACT FROM AUTHOR]- Published
- 2017
- Full Text
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17. Spectral modulation of a bistable liquid-crystal photonic structure by the polarization effect
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Wei Lee, Yu Cheng Hsiao, Ivan V. Timofeev, Victor Ya. Zyryanov, and Yi Hong Zou
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Birefringence ,Materials science ,Bistability ,business.industry ,Homeotropic alignment ,Physics::Optics ,Polarization (waves) ,Electronic, Optical and Magnetic Materials ,Wavelength ,Optics ,Liquid crystal ,Optoelectronics ,Photonics ,business ,Photonic crystal - Abstract
The light polarization has an effect on spectral properties of a multilayered photonic crystal infiltrated with a bistable chiral-tilted homeotropic nematic liquid crystal (LC) as a defect layer. By varying the direction of polarization of incident, linearly polarized light interacting with the birefringent LC, the tunability of defect modes in wavelength and amplitude and the broadening of the low-transmittance range can be realized in the transmission spectrum. The LC features two optically stable states and two voltage-sustained states. The bistability makes the device of low energy consumption. Such a hybrid can be used as not only a wavelength selector, optical shutter or multichannel switch but also a stopband-tunable device.
- Published
- 2013
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