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1.
Chem Biodivers ; 19(11): e202200762, 2022 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-36177989

RESUMEN

Two new eremophilane-type sesquiterpenoids, sagittacins F and G (1 and 2), together with one known isomer of sagittacin F (3) were isolated from the leaves and stems of Ligularia sagitta. Their structures were elucidated by interpretation of spectroscopic data and the absolute configurations of 1 and 3 were determined by X-ray spectroscopy. Compound 1 belongs to a rare class of eremophilane-type sesquiterpenoid featuring an α-oriented hydroxy group at C-1. A nitric oxide (NO) production inhibitory assay was applied to evaluate their anti-inflammatory activities by using LPS-induced RAW 264.7 cells. Compounds 2 and 3 exhibited modest NO production inhibitions with IC50 values of 45.15±2.72 and 49.83±2.34 µM, respectively.


Asunto(s)
Ligularia , Sesquiterpenos , Ratones , Animales , Sesquiterpenos Policíclicos , Estructura Molecular , Sesquiterpenos/farmacología , Sesquiterpenos/química , Células RAW 264.7 , Óxido Nítrico
2.
Curr Microbiol ; 76(7): 904-908, 2019 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-31104137

RESUMEN

In the present study, nine compounds (1-9) were isolated from Colletotrichum gloeosporioides (an endophytic fungus from Uncaria rhynchophylla) which was cultured in wheat bran medium. Their structures were elucidated as 4-Epi-14-hydroxy-10, 23-dihydro-24, 25-dehydroaflavinine (1), 10, 23-Dihydro-24,25 -dehydro-21-oxoaflavinine (2), Ergosterol (3), Ergosterol peroxide (4), Mellein (5), 4, 5-dihydroblumenol A (6), Colletotrichine A (7), Cyclo(L-leucyl-L-leucyl) (8), and Brevianamide F (9) based on NMR spectral data, as well as comparing with previous literature data. This is the first report about the isolation of compounds 1-2, 6, and 8-9 from Colletotrichum genus. All compounds were tested for their phosphoinositide 3-kinase (PI3Kα) inhibitory activity. Compounds 8 and 9 showed potent PI3K α inhibitory activity with IC50 values of 38.1 and 4.8 µM, respectively, while the other compounds showed very weak activity at a concentration of 20 µg/mL.


Asunto(s)
Colletotrichum/metabolismo , Inhibidores Enzimáticos/química , Interacciones Huésped-Patógeno , Inhibidores de las Quinasa Fosfoinosítidos-3 , Uncaria/enzimología , Uncaria/microbiología , Colletotrichum/química , Endófitos/química , Endófitos/metabolismo , Inhibidores Enzimáticos/aislamiento & purificación , Concentración 50 Inhibidora , Estructura Molecular , Metabolismo Secundario
3.
Zhong Yao Cai ; 39(8): 1775-8, 2016 Aug.
Artículo en Zh | MEDLINE | ID: mdl-30204382

RESUMEN

Objective: To study the chemical constituents and monoamine oxidase inhibitory activity of Rhinocladiella sp. lgt-3,which was an endophytic fungus isolated from Tripterygium wilfordii. Methods: Compounds were isolated from by various column chromatography. The structures were elucidated by various spectral data. The activity was tested by using 96-well micro-plated method. Results: 10 compounds were isolated and identified as 3,4-dihydro-3,4,8-trihydroxy-1( 2H)-naphthalenone( 1),( 3R,4R)-4-hydroxymellein( 2),O-methylmellein( 3),4-( 2-hydroxybutynoxy) benzoic acid( 4),2,4-dihydroxy-6-(( R)-4-hydroxy-2-oxopentyl)-3-methylbenzaldehyde( 5),( Z)-N-( 4-hydroxystyryl) formamide( 6), aspterric acid( 7),bufotenin( 8),5-hydroxy-N,N-dimethyltryptamine-N-oxide( 9)and 5-methoxy-N,N-dimethyltryptamine( 10). Compounds 1,8 ~ 10 showed moderate anti-monoamine oxidase activity with IC50 values of 32,36,50,56 µmol/L, respectively. Conclusion: Compounds 3 ~ 10 are isolated from Rhinocladiella genus for the first time and the anti-monoamine oxidase activity of compound 1 are reported for the first time.

4.
Zhong Yao Cai ; 39(3): 540-3, 2016 Mar.
Artículo en Zh | MEDLINE | ID: mdl-30088877

RESUMEN

Objective: To study the chemical constituents and monoamine oxidase inhibitory activity of Talaromyces wortmannii,an endophytic fungus was isolated from Tripterygium wilfordii. Methods: Chemical constituents were isolated from Talaromyces wortmannii by various column chromatography. The structures were elucidated by various spectral data. The activity was tested by using 96-well micro-plated method. Results: Ten compounds were identified as wortmannilactone A( 1),( +) brefeldin A( 2),( 2E,4R*)-4-hydroxy-4-{( 1R*,2S*)-4-oxo-2-[( 1E)-6-oxohept-1-en-1-yl]cyclopentyl} but-2-enoic acid( 3),phaseic acid( 4),deacetylisowortmin( 5),talaperoxide C( 6),brevianamide F( 7),cyclo( D-N-methyl-Leu-L-Trp)( 8),physcione( 9) and chrysophanol( 10). Compound 7 showed moderate anti-monoamine oxidase activity with the IC50 value of 55 µmol / L. Conclusion: Compounds 2 ~ 4,7 ~ 10 are isolated from Talaromyces genus for the first time,and the anti-monoamine oxidase activity of compound 7 is reported for the first time


Asunto(s)
Tripterygium , Cromatografía , Dipéptidos , Alcaloides Indólicos , Estructura Molecular , Monoaminooxidasa , Oxidación-Reducción , Sesquiterpenos , Talaromyces
5.
Nat Prod Res ; 37(2): 204-215, 2023 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-34348525

RESUMEN

Four undescribed bisbenzylisoquinoline alkaloids, designated as Stephtetrandrine A-D, were isolated from the roots of Stephania tetrandra. Their structures were elucidated by IR, HRESIMS, ECD spectra, 1 D and 2 D NMR spectra and comparison with the literature data. Additional five known compounds (limacine, tetrandrine, N-trans-Feruloyltyramine, 2'-N-chloromethyltetrandrine, 2,2'-N-N-dichloromethyltetrandrine) were also isolated. N-trans-Feruloyltyramine was isolated from Stephania tetrandra for the first time. The isolated compounds were tested for monoamine oxidase, acetylcholinesterase, phosphoinositide 3-kinase α and human hepatoma cell HepG2 inhibitory activities. Stephtetrandrine C showed obvious inhibitory effect on human hepatoma HepG2, with IC50 value of 16.2 µM. Limacine and 2'-N-chloromethyltetrandrine showed moderate monoamine oxidase inhibitory effect with the IC50 values of 37.7 and 29.2 µM, respectively.


Asunto(s)
Alcaloides , Bencilisoquinolinas , Carcinoma Hepatocelular , Neoplasias Hepáticas , Stephania tetrandra , Stephania , Humanos , Stephania tetrandra/química , Acetilcolinesterasa , Fosfatidilinositol 3-Quinasas , Alcaloides/farmacología , Alcaloides/química , Bencilisoquinolinas/farmacología , Stephania/química , Estructura Molecular
6.
Phytochemistry ; 209: 113613, 2023 May.
Artículo en Inglés | MEDLINE | ID: mdl-36804478

RESUMEN

Three unprecedented thioether-linked dimeric pyrimidines, namely ligusticumines A-C, together with twelve known compounds were isolated and identified from the traditional Chinese medicinal-edible herb, Ligusticum striatum DC. The structures of all the isolated compounds were determined from NMR, HRESIMS and X-ray diffraction spectroscopies. Additionally, a novel 3-step synthetic route was developed to synthesize ligusticumine C by substitution, thiolation and coupling, with an overall yield of 5.4%. The inhibitory activities of the isolated compounds against phosphatidylinositol 3-kinase (PI3K) were tested, of which, (3S)-butylphthalide, a characteristic component of L. striatum, showed a potent inhibitory effect on PI3Kα (IC50: 3.6 µg/mL).


Asunto(s)
Ligusticum , Plantas Medicinales , Ligusticum/química , Fosfatidilinositol 3-Quinasas , Pirimidinas/química , Pirimidinas/farmacología , Espectroscopía de Resonancia Magnética
7.
Planta Med ; 77(14): 1610-6, 2011 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-21412694

RESUMEN

Six new sesquiterpenoids, linderanlide A-F (1-5 and 12), and nine previously reported sesquiterpenoids (6-11 and 13-15) have been isolated from the root tubers of Lindera aggregata. The new structures have been elucidated by extensive spectroscopic interpretation, including UV, IR, NMR, HR-ESI-MS, and CD spectra. The structures of compounds 1, 2, 6, 7, and 9 were further confirmed by single-crystal X-ray diffraction analysis. The absolute configurations of compounds 3-5 were determined by CD spectral analysis.


Asunto(s)
Medicamentos Herbarios Chinos/química , Lindera/química , Sesquiterpenos/química , Cristalografía por Rayos X , Espectroscopía de Resonancia Magnética , Medicina Tradicional China , Conformación Molecular , Raíces de Plantas/química , Plantas Medicinales/química , Sesquiterpenos/aislamiento & purificación , Espectrometría de Masa por Ionización de Electrospray
8.
Phytochem Anal ; 22(6): 509-15, 2011.
Artículo en Inglés | MEDLINE | ID: mdl-21433160

RESUMEN

INTRODUCTION: Thin-layer chromatography (TLC) bioautographic method is a simple and rapid method to screen acetylcholinesterase inhibitors from plant extracts. However, the high consumption of enzyme (6 U/mL) in current methods makes the procedure expensive, which is an obstacle to scientific research centers lacking funding. OBJECTIVE: To develop a new low-cost TLC bioautographic method. METHODOLOGY: A series of compounds, as substrates, were synthesised and their ability to be hydrolysed by acetylcholinesterase was evaluated by the HPLC method. RESULTS: 4-Methoxyphenyl acetate (14) was proved to be an appropriate substrate for TLC bioautographic assay. Therefore a new and cheap TLC bioautographic assay was set up. The mechanism of this new method is that the enzyme converts 4-methoxylphenyl acetate into 4-methoxyphenol, which reacts with a solution of potassium ferricyanide ([K3(FeCN)6]) and iron chloride hexahydrate (FeCl3·6H2O) to make an aquamarine blue coloured background on the TLC plates. Regions of the TLC plate which contain acetylcholinesterase inhibitors show up as light yellow spots against the background. The consumption of enzyme (1 U/mL) in the new method is low and the detection limit of two known acetylcholinesterase inhibitors, huperzine A (0.0001 µg) and physostigmine (0.001 µg), for this assay are close to published values. CONCLUSION: A low-cost TLC bioautographic method was developed, which will benefit research groups pursuing natural acetylcholinesterase inhibitors.


Asunto(s)
Inhibidores de la Colinesterasa/química , Cromatografía en Capa Delgada/métodos , Pruebas de Enzimas/métodos , Fenilacetatos/química , Acetilación , Alcaloides/química , Anisoles/química , Cloruros/química , Cromatografía Líquida de Alta Presión , Compuestos Cromogénicos/química , Color , Compuestos Férricos/química , Ferricianuros/química , Hidrólisis , Límite de Detección , Estructura Molecular , Phellodendron/química , Fenilacetatos/síntesis química , Fisostigmina/química , Corteza de la Planta/química , Extractos Vegetales/química , Sesquiterpenos/química , Espectrofotometría Ultravioleta , Especificidad por Sustrato
9.
Fitoterapia ; 153: 104948, 2021 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-34087409

RESUMEN

A norbisabolane and an arabitol benzoate, Talaromarnine A (1), Talaromarnine B (2), together with eight known compounds were obtained from cultures of Talaromyces marneffei, an endophytic fungus of Epilobium angustifolium. Their structures were elucidated by IR, MS, 1D and 2D NMR spectra, and their absolute configuration was determined by single-crystal X-ray diffraction and molecular computation. These compounds were tested for monoamine oxidase, acetylcholinesterase and PI3K inhibitory activity, but no compounds exhibited significant activities.


Asunto(s)
Benzoatos/aislamiento & purificación , Epilobium/microbiología , Alcoholes del Azúcar/aislamiento & purificación , Talaromyces/química , Benzoatos/química , China , Endófitos/química , Estructura Molecular , Alcoholes del Azúcar/química
10.
Nat Prod Res ; 35(19): 3204-3209, 2021 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-31711315

RESUMEN

A new phenylpentenol, wortmannine H (1) was isolated from Talaromyces wortmannii LGT-4, an endophytic fungus of Tripterygium wilfordii. The structure of 1 was elucidated by IR, MS, 1D and 2D NMR spectra and comparison of the experimental and calculated optical rotatory dispersion (ORD). Monoamine oxidase (MAO), acetylcholinesterase (AChE) and phosphoinositide 3-kinase (PI3Kα) inhibitory activities of 1 was also tested. The compound did not show good biological activity.


Asunto(s)
Pentanonas/química , Talaromyces , Acetilcolinesterasa , Endófitos , Estructura Molecular , Monoaminooxidasa , Pentanonas/aislamiento & purificación , Fosfatidilinositol 3-Quinasas , Talaromyces/química
11.
Iran J Pharm Res ; 19(2): 259-263, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-33224231

RESUMEN

In the present study, nine compounds (1-9) were isolated from Talaromyces wortmannii LGT-4 (an endophytic fungus from Tripterygium wilfordi) which was cultured in CYM Medium. Their structures were determined as 4-hydroxyphthalide (1), Fumitremorgin C (2), Ergosterol (3), 3-(2-hydroxypropyl)-8-hydroxy-3,4- dihydroisocoumarin (4), Cis-cyclo(L-Ala-L-Pro) (5), 6-Amino-3-(4-hydroxybenzyl)- 1,4-diazonane-2,5-dione (6), Aspergillumarin B (7), Deacetylisowortmin B (8), and Entonaemin A (9) based on NMR spectral data, as well as comparing with previous literature data. This is the first report of the isolation of compounds 1-2 and 4-7 from Talaromyces genus. All compounds were tested for their monoamine oxidase and phosphoinositide 3-kinase (PI3Kα) inhibitory activities. Compound 1, 5 showed moderate anti-monoamine oxidase activity with IC50 value of 35 µg/mL, 28 µg/mL, respectively. Compound 9 showed PI3Kα inhibitory activity with IC50 value of 10.3 µg/mL.

12.
Nat Prod Res ; 34(19): 2802-2808, 2020 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-30929454

RESUMEN

Two new compounds Talaromycin A (1) and Talaromycin B (2) were isolated from a liquid culture of Talaromyces aurantiacus. The structures of 1 and 2 were elucidated by IR, MS, 1D and 2D NMR spectra and comparison of the experimental and calculated electronic circular dichroism spectra. Additional known compounds (3-6) were also isolated. These compounds were tested for monoamine oxidase, acetylcholinesterase and PI3K inhibitory activity, but showed only weak activity.


Asunto(s)
Inhibidores Enzimáticos/química , Inhibidores Enzimáticos/farmacología , Compuestos de Espiro/química , Talaromyces/química , Inhibidores de la Colinesterasa/química , Inhibidores de la Colinesterasa/farmacología , Dicroismo Circular , Evaluación Preclínica de Medicamentos , Endófitos/química , Inhibidores Enzimáticos/aislamiento & purificación , Espectroscopía de Resonancia Magnética , Estructura Molecular , Inhibidores de la Monoaminooxidasa/química , Inhibidores de la Monoaminooxidasa/farmacología , Inhibidores de las Quinasa Fosfoinosítidos-3/química , Inhibidores de las Quinasa Fosfoinosítidos-3/farmacología , Compuestos de Espiro/aislamiento & purificación , Compuestos de Espiro/farmacología
13.
Nat Prod Res ; 33(1): 108-112, 2019 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-29421923

RESUMEN

One new compound, colletotrichine B (1), was produced by the fungal Colletotrichum gloeosporioides GT-7. The structure of 1 was elucidated on the basis of spectroscopic analysis and X-ray crystallographic analysis. Monoamine oxidase (MAO), acetylcholinesterase (AChE) and phosphoinositide 3-kinase (PI3Kα) inhibitory activity of 1 was also evaluated. Compound 1 showed only AChE inhibiting activity with IC50 value of 38.0 ± 2.67 µg/mL.


Asunto(s)
Inhibidores de la Colinesterasa/aislamiento & purificación , Colletotrichum/química , Endófitos/química , Sesquiterpenos/aislamiento & purificación , Uncaria/microbiología , Inhibidores de la Colinesterasa/química , Concentración 50 Inhibidora , Estructura Molecular , Inhibidores de la Monoaminooxidasa/química , Inhibidores de la Monoaminooxidasa/aislamiento & purificación , Inhibidores de las Quinasa Fosfoinosítidos-3
14.
Zhongguo Zhong Yao Za Zhi ; 33(3): 269-72, 2008 Feb.
Artículo en Zh | MEDLINE | ID: mdl-18536463

RESUMEN

OBJECTIVE: To study the chemical constituents of the root of Hemerocallis fulva. METHOD: Compounds were isolated by repeated silica gel, Sephadex LH-20, MCI gel, etc. column chromatography and their structures were determined by spectral analyses and physicochemical properties. RESULT: From the n-butanol fraction of the EtOH extract of the roots of H. fulva, 9 glycosides were isolated and identified as sweroside (1), laganin (2), picraquassioside C (3), puerarin (4), 3'-methoxypuerarin (5), 7-hydro xylnaphthalide-O-beta-D-glucopyranoside (6), orcinol-3-O-beta-glucopyranoside (7), HN saponin F (8), hederagenin-3-0-beta D-glucopyranosyl-(1-3)-alpha-L-arabinopyranoside-28-O-beta-D-glucopyranosyl ester (9). CONCLUSION: Compounds 1-9 were isolated from the genus Hemerocallis for the first time.


Asunto(s)
Hemerocallis/química , Raíces de Plantas/química , Glucósidos/química , Glucósidos/aislamiento & purificación , Glucósidos Iridoides , Iridoides/química , Iridoides/aislamiento & purificación , Isoflavonas/química , Isoflavonas/aislamiento & purificación , Espectroscopía de Resonancia Magnética , Saponinas/química , Saponinas/aislamiento & purificación
15.
Zhong Yao Cai ; 31(6): 855-7, 2008 Jun.
Artículo en Zh | MEDLINE | ID: mdl-18998569

RESUMEN

OBJECTIVE: To investigate the chemical constituents of the bark of Caragana opulens. METHODS: The constituents of the CH3Cl-soluble portion in the 95% ethanol extract were isolated and purified by means of chromatography. The compounds were identified by their physical characteristics and spectral features. RESULTS: Eight compounds were isolated and identified as encelin(1), (+)-13-Hydroxyspathulenol(2), (+) -3alpha,9beta-aromaden dranediol(3), quercetin(4), penduletin(5), lupenol(6), Lup-20(29) -en-3-one (7), beta-sitosterol(8). CONCLUSION: Compounds 1, 2, 5, 7 are isolated for the first time from Caragana genus.


Asunto(s)
Caragana/química , Plantas Medicinales/química , Quercetina/aislamiento & purificación , Triterpenos/aislamiento & purificación , Espectroscopía de Resonancia Magnética , Corteza de la Planta/química , Quercetina/química , Triterpenos/química
16.
Nat Prod Res ; 32(8): 880-884, 2018 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-28805453

RESUMEN

One new compound, Colletotrichine A (1), was produced by the fungal Colletotrichum gloeosporioides GT-7. The structure was established by 1D and 2D NMR spectra. Monoamine oxidase (MAO) and acetylcholinesterase (AChE) inhibitory activity of 1 was also evaluated. Compound 1 showed AChE-inhibiting activity with IC50 value of 28 µg/mL.


Asunto(s)
Inhibidores de la Colinesterasa/química , Colletotrichum/química , Inhibidores de la Monoaminooxidasa/química , Sesquiterpenos/química , Uncaria/microbiología , Inhibidores de la Colinesterasa/farmacología , Endófitos/química , Concentración 50 Inhibidora , Inhibidores de la Monoaminooxidasa/farmacología , Sesquiterpenos/farmacología
18.
Nat Prod Res ; 31(21): 2527-2530, 2017 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-28423923

RESUMEN

A new wortmannine derivative named wortmannine E (1) was isolated from Talaromyces wortmannii LGT-4, an endophytic fungus of Tripterygium wilfordii. Its structure was established by 1D and 2D NMR spectra.


Asunto(s)
Androstadienos/química , Talaromyces/química , Tripterygium/microbiología , Androstadienos/aislamiento & purificación , Endófitos/química , Espectroscopía de Resonancia Magnética , Estructura Molecular , Wortmanina
19.
Mar Environ Res ; 131: 183-194, 2017 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-29017729

RESUMEN

Contamination and eutrophication have caused serious ecological events (such as algal bloom) in coastal area. During this ecological process, microbial community structure is critical for algal bloom succession. The diversity and composition of bacteria and archaea communities in algal blooms have been widely investigated; however, those of fungi are poorly understood. To fill this gap, we used pyrosequencing and correlation approaches to assess fungal patterns and associations during a dinoflagellate (Noctiluca scintillans) bloom. Phylum level fungal types were predominated by Ascomycota, Chytridiomycota, Mucoromycotina, and Basidiomycota. At the genus level drastic changes were observed with Hysteropatella, Malassezia and Saitoella dominating during the initial bloom stage, while Malassezia was most abundant (>50%) during onset and peak-bloom stages. Saitoella and Lipomyces gradually became more abundant and, in the decline stage, contributed almost 70% of sequences. In the terminal stage of the bloom, Rozella increased rapidly to a maximum of 50-60%. Fungal population structure was significantly influenced by temperature and substrate (N and P) availability (P < 0.05). Inter-specific network analyses demonstrated that Rozella and Saitoella fungi strongly impacted the ecological trajectory of N. scintillans. The functional prediction show that symbiotrophic fungi was dominated in the onset stage; saprotroph type was the primary member present during the exponential growth period; whereas pathogentroph type fungi enriched in decline phase. Overall, fungal communities and functions correlated significantly with N. scintillans processes, suggesting that they may regulate dinoflagellate bloom fates. Our results will facilitate deeper understanding of the ecological importance of marine fungi and their roles in algal bloom formation and collapse.


Asunto(s)
Dinoflagelados/fisiología , Monitoreo del Ambiente , Eutrofización , Diatomeas , Ecosistema , Agua de Mar
20.
J Pharm Biomed Anal ; 40(5): 1263-7, 2006 Mar 18.
Artículo en Inglés | MEDLINE | ID: mdl-16242892

RESUMEN

Three known and five new steroidal compounds as impurities in spironolactone were isolated from the enriched mother liquor by using various chromatographic methods. Their structures were elucidated by spectrometric analysis. New compounds were characterized as 3-(3,3-dimethoxy-5 alpha,7 alpha-epidithio-17beta-hydroxy-4-androstan-17 alpha-yl) propionic acid gamma-lactone (6); 3-(3-oxo-7 alpha-acetylthio-6 beta,17beta-dihydroxy-4-androsten-17 alpha-yl) propionic acid gamma-lactone (7); 7 alpha-acetylthio-17beta-20-isopropylidendioxy-21-nor-17 alpha-pregn-4-en-3-one (8); 7 alpha-acetylthio-3-oxo-pregna-4,17(20)i-dien-22-oic acid methyl ester (9) and 7 alpha-acetylthio-17-methyl-18-nor-androsta-4-en-3-one (10).


Asunto(s)
Diuréticos/química , Espironolactona/química , Cromatografía Líquida de Alta Presión , Diuréticos/aislamiento & purificación , Indicadores y Reactivos , Espectroscopía de Resonancia Magnética , Espectrometría de Masas , Conformación Molecular , Control de Calidad , Espectroscopía Infrarroja por Transformada de Fourier , Espironolactona/aislamiento & purificación
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