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2.
Sci Rep ; 13(1): 14408, 2023 Sep 02.
Artículo en Inglés | MEDLINE | ID: mdl-37660225

RESUMEN

In this study, a transversal ultrasonic vibration-assisted riveting (TUVAR) process was developed to improve the uniformity of CFRP riveted lap joint interference-fit size, which provided a possibility for the quantization of riveted joint interference-fit sizes. The relationship between the process parameters of vibration amplitude, vibration duration, and roughness with interference-fit sizes by algorithms, through the minimum coefficient variance of interference-fit size (ICV-min) to confirm the riveting process parameters of the quantized average interference-fit sizes (IA). The experimental verification results showed that the mean absolute percentage error of measured IA and predicted IA is less than 10%. Furthermore, the tensile tests were carried out to investigate the effect of interference-fit size {1.4%, 1.6%, 1.8%, and 2.0%} on mechanical performances of CFRP riveted lap joints by TUVAR, and the tensile strength presents first-up then down with the interference-fit size increase, the maximum ultimate tensile strength is the riveted lap joint with the interference-fit size of 2.0%. Hence, the quantitative optimization method can well predict the riveting process parameters corresponding to the most uniform interference-fit size.

3.
Chem Biodivers ; 20(3): e202201185, 2023 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-36795028

RESUMEN

Two new bibenzyl-phenylpropane hybrids, dendrophenols A and B (1 and 2), along with nine known bibenzyls, were isolated from the aerial part of Dendrobium devonianum Paxt. Their structures were determined by extensive spectroscopic methods and methylation. Bioassays revealed that compounds 1-9 were specifically immunosuppressive to T lymphocytes with IC50 values ranging from 0.41 to 9.4 µM, of which compounds 1 (IC50 =1.62 µM) and 2 (IC50 =0.41 µM) were promising immunosuppressive agents for T lymphocytes with the selectivity indices of 19.9 and 79.5, respectively.


Asunto(s)
Bibencilos , Dendrobium , Bibencilos/farmacología , Bibencilos/química , Dendrobium/química , Depuradores de Radicales Libres/química , Espectroscopía de Resonancia Magnética , Estructura Molecular
4.
Bioorg Chem ; 134: 106438, 2023 05.
Artículo en Inglés | MEDLINE | ID: mdl-36848715

RESUMEN

Horsfiequinone G (1), a dimeric diarylpropane featuring an unprecedentedly oxo-6/7/6 fused ring system, a new flavane, horsfielenide F (2), three naturally occurring spirocyclic monomers containing all-carbon quaternary centers, horspirotone A (3), horspirotone B (4), and methyl spirobroussonin B (5), along with horsfiequinone A (6) were isolated from Horsfieldia kingii. Their structures and absolute configurations were determined by the inspection of extensive spectroscopic data and electronic circular dichroism (ECD) calculations. Biological evaluations of these isolates revealed that compounds 1 - 3 and 5 - 6 exhibited specifically immunosuppressive activities against Con A-induced T lymphocytes with IC50 values ranging from 2.07 to 12.34 µM (selectivity indices = 2.3-25.2). Compound 1 also suppressed the secretion of inflammatory factors like IL-1ß and IL-6 in RAW264.7 cells which could present a new class of nonsteroidal anti-inflammatory agent. Finally, the primary structure-activity relationship (SAR) was also discussed.


Asunto(s)
Antiinflamatorios no Esteroideos , Inmunosupresores , Antiinflamatorios no Esteroideos/farmacología , Carbono , Dicroismo Circular , Inmunosupresores/farmacología , Estructura Molecular , Relación Estructura-Actividad
5.
Chem Biodivers ; 19(6): e202200259, 2022 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-35510718

RESUMEN

Two new isopentenyl bibenzyls, denchrysotonols A and B (1-2), along with 26 known phenolic compounds, were isolated from the stems of cultivated Dendrobium chrysotoxum Lindl. Their chemical structures were clearly elucidated by extensive spectroscopic analysis. Biological evaluation of isolated compounds revealed that phenanthrenes (14, 16-17, 20, and 22) and fluorenone 25 exhibited anti-inflammatory activities which inhibited nitric oxide (NO) production in LPS-activated RAW264.7 macrophages with the IC50 values ranging from 9.4 to 32.5 µM. Moreover, bibenzyls (1-2 and 7) showed good anti-proliferative activities against triple-negative breast cancer (TNBC) cells (HCC1806, MDA-MB-231, and MB-MB-468) with the IC50 values ranging from 8.1 to 18.6 µM, of which 1 and 2 seemed preferentially inhibit MDA-MB-231 cells.


Asunto(s)
Bibencilos , Dendrobium , Antiinflamatorios/farmacología , Bibencilos/química , Bibencilos/farmacología , Dendrobium/química , Macrófagos , Estructura Molecular , Fenoles/farmacología
6.
Nat Prod Res ; 35(6): 1019-1023, 2021 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-31238722

RESUMEN

Chemical investigation of the twigs of Cryptocarya impressinervia yielded 23 known compounds including 8 lignans, 3 phenylpropionates, 1 xanthone, 3 flavonoids, 1 phenylpropanoid, 1 substitued phenol, 1 triterpenoid, 3 sterols and 2 aliphatic compounds. All the compounds was isolated from C. impressinervia for the first time. 9,9'-O-Di-feruloyl-(-)-secoisolariciresinol (1) displayed significant cytotoxic activities on five human cancer cell lines (HL-60, SMMC-7721, A-549, MCF-7 and SW-480), with IC50 values of 3.58, 4.55, 6.39, 5.09 and 4.80 µM, respectively. Rhusemialin A (2) showed significant activity against HL-60 with IC50 of 3.69 µM. Dihydrosinapyl ferulate (3) displayed moderate cytotoxic activities against five tested human cancer cell lines. To the best of our knowledge, this is the first report on the constituents of C. impressinervia and cytotoxic activities of compounds 1-3 on the tested cancer cell lines.


Asunto(s)
Cryptocarya/química , Lignanos/farmacología , Antineoplásicos/farmacología , Antineoplásicos Fitogénicos/química , Butileno Glicoles/farmacología , Muerte Celular/efectos de los fármacos , Línea Celular Tumoral , Flavonoides/química , Humanos , Concentración 50 Inhibidora , Lignanos/química , Triterpenos/química , Triterpenos/farmacología
7.
Nat Prod Res ; 35(7): 1127-1133, 2021 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-31322421

RESUMEN

Three new diarylpropanes (1-3), including two diarylpropane glycosides, and three known ones, were isolated from 70% aqueous acetone extract of the twigs and leaves of Horsfieldia kingii. Their structures were elucidated by spectroscopic analysis. Bioactive evaluation of inhibition on DDC enzyme assay showed that the new compounds were inactive.


Asunto(s)
Flavonoides/aislamiento & purificación , Myristicaceae/química , Inhibidores de Descarboxilasas de Aminoácidos Aromáticos/química , Inhibidores de Descarboxilasas de Aminoácidos Aromáticos/farmacología , Dopa-Decarboxilasa/metabolismo , Flavonoides/química , Flavonoides/farmacología , Glicósidos/química , Glicósidos/farmacología , Humanos , Extractos Vegetales/química , Hojas de la Planta/química , Espectroscopía de Protones por Resonancia Magnética
8.
Nat Prod Res ; 34(9): 1297-1302, 2020 May.
Artículo en Inglés | MEDLINE | ID: mdl-30760044

RESUMEN

Two new eremophilane sesquiterpenoides, 6α,9α-dihydroxyeremophilenolide (1), and 1ß,10ß-dihydroxyeremophilenolide (2), along with ten known eremophilane sesquiterpenoides (3-12) were isolated from the aerial parts of Ligularia dictyoneura (Franch.) Hand.-Mazz. Their structures were elucidated by means of extensive spectroscopic analysis. Compounds 3-6 were assessed for their cytotoxicity against five human cancer cell lines (HL-60, SMMC-7721, A-549, MCF-7 and SW-480), and the result showed that they had no activity.


Asunto(s)
Ligularia/química , Sesquiterpenos Policíclicos/química , Sesquiterpenos Policíclicos/farmacología , Antineoplásicos Fitogénicos/química , Antineoplásicos Fitogénicos/farmacología , Línea Celular Tumoral , Ensayos de Selección de Medicamentos Antitumorales , Humanos , Estructura Molecular , Componentes Aéreos de las Plantas/química , Espectrometría de Masa por Ionización de Electrospray
9.
J Asian Nat Prod Res ; 22(4): 353-358, 2020 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-30835549

RESUMEN

Twelve dihydrostilbenes (including five new analogues) were prepared by the Witting-Hornor reaction from appropriate aromatic aldehydes and phosphonate esters, followed by hydrogenation in five steps. The in vitro inhibition activity against human neutrophil elastase (HNE) of these dihydrostilbenes was evaluated, and three 1,2-dihydroxylated dihydrostilbenes (6b, 6j, and 6l) exhibited stronger inhibitory activity against HNE than other analogues.


Asunto(s)
Dihidrostilbenoides , Elastasa de Leucocito , Humanos , Estructura Molecular
10.
Nat Prod Res ; 34(3): 390-397, 2020 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-30600696

RESUMEN

Twenty-seven compounds, including a new diarypropane and two new lignans were isolated from the twigs and leaves of Endocomia macrocoma. Their structures were elucidated by spectroscopic analysis. Cytotoxicity evaluation of the new compounds against five human tumor lines showed no inhibitory effects.[Formula: see text].


Asunto(s)
Lignanos/aislamiento & purificación , Myristicaceae/química , Propano/aislamiento & purificación , Línea Celular Tumoral , Ensayos de Selección de Medicamentos Antitumorales , Humanos , Lignanos/química , Lignanos/farmacología , Estructura Molecular , Extractos Vegetales/química , Hojas de la Planta/química , Propano/química , Propano/farmacología
11.
Org Lett ; 21(10): 3678-3681, 2019 05 17.
Artículo en Inglés | MEDLINE | ID: mdl-31038317

RESUMEN

Horisfieldones A (1) and B (2), two dimeric diarylpropanes featuring an unprecedentedly aromatic ring-contracted framework, were isolated from Horsfieldia kingii. Their structures and absolute configurations were determined by the inspection of extensive spectroscopic data and electronic circular dichroism calculations. Molecular modeling analysis, in vitro enzyme-based bioassays, and structure-activity relationship analysis of these isolates revealed that (+)-1 (IC50 = 35.1 ± 3.9 µM, SI > 11.4) could present a new class of human DOPA decarboxylase inhibitor.


Asunto(s)
Dopa-Decarboxilasa/farmacología , Propano/farmacología , Dicroismo Circular , Dopa-Decarboxilasa/química , Humanos , Concentración 50 Inhibidora , Modelos Moleculares , Estructura Molecular , Propano/análogos & derivados , Propano/química , Relación Estructura-Actividad
12.
Nat Prod Res ; 33(2): 239-243, 2019 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-29473435

RESUMEN

A new neolignan, 5-(3″-acetoxypropyl)-2-(4'-hydroxy-3'-methoxyphenyl)-7-methoxy-3-methylbenzofuran (1) along with nine analogues were isolated from the thorns of Gleditsia japonica var. delavayi by solvent extraction and repeated column chromatography. Their structures were elucidated by means of extensive spectroscopic analysis including 1D, 2D-NMR techniques and HR-ESIMS. All the isolates were reported for the first time from this species.


Asunto(s)
Gleditsia/química , Lignanos/aislamiento & purificación , Lignanos/química , Estructura Molecular , Estructuras de las Plantas/química , Análisis Espectral
13.
J Asian Nat Prod Res ; 21(2): 129-133, 2019 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-29069925

RESUMEN

Two new picrotoxane-type sesquiterpenoid lactones, dendrowillins A (1) and B (2), together with five known sesquiterpenoids, (-)-picrotin (3), α-dihydropicrotoxinin (4), dendronobilin B (5), amoenin (6), and (-)-10ß,13,14-trihydroxyalloaromadendrane (7), were isolated from the whole plants of Dendrobium williamsonii. Their structures were elucidated by means of extensive spectroscopic analysis.


Asunto(s)
Dendrobium/química , Lactonas/química , Sesquiterpenos/química , Estructura Molecular
14.
Nat Prod Res ; 33(8): 1158-1161, 2019 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-29656654

RESUMEN

A new galloyl glucoside, 2,6-di-O-acetyl 1-O-galloyl ß-D-glucose (1), along with five known phenolic compounds were isolated from the whole plants of Lotus corniculatus. Their structures were elucidated by means of extensive spectroscopic analysis. Compound 1 was assessed for its cytotoxicity against five human tumour lines (HL-60, SMMC-7721, A-549, MCF-7 and SW-480), and the result showed that it had no activity.


Asunto(s)
Glucósidos/química , Lotus/química , Extractos Vegetales/química , Línea Celular Tumoral , Ensayos de Selección de Medicamentos Antitumorales , Glucósidos/aislamiento & purificación , Glucósidos/farmacología , Humanos , Taninos Hidrolizables , Estructura Molecular , Fenoles/química , Fenoles/aislamiento & purificación , Análisis Espectral
15.
Nat Prod Res ; 33(1): 95-100, 2019 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-29447479

RESUMEN

Two new dibenzylbutyrolactol lignans and three known dibenzylbutyrolactone lignans were isolated from the twigs and leaves of Horsfieldia kingii. Their structures were elucidated by spectroscopic analysis. Cytotoxicity evaluation of these compounds against five human tumour lines showed no inhibitory effects.


Asunto(s)
Lignanos/aislamiento & purificación , Myristicaceae/química , Extractos Vegetales/química , Línea Celular Tumoral , Ensayos de Selección de Medicamentos Antitumorales , Humanos , Lignanos/química , Lignanos/toxicidad , Estructura Molecular , Hojas de la Planta/química , Análisis Espectral
16.
J Asian Nat Prod Res ; 21(4): 331-336, 2019 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-29334258

RESUMEN

Two new phenylpropanoid esters bobulretulates A (1) and B (2), together with eleven known compounds, were isolated from the whole plants of Bulbophyllum retusiusculum. Their structures were elucidated by means of extensive spectroscopic analysis.


Asunto(s)
Orchidaceae/química , Fenilpropionatos/aislamiento & purificación , Ésteres/química , Ésteres/aislamiento & purificación , Fenilpropionatos/química
17.
Nat Prod Res ; 32(2): 162-166, 2018 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-28641463

RESUMEN

Five compounds, including a new dimeric diarylpropane, were isolated from the petroleum ether extract of the twigs and leaves of Horsfieldia tetratepala. The structures of these compounds were elucidated by spectroscopic analysis. Moreover, the antiproliferative activities of these compounds were tested on cancer cell lines, but none is active.


Asunto(s)
Myristicaceae/química , Extractos Vegetales/química , Hojas de la Planta/química , Antineoplásicos/aislamiento & purificación , Antineoplásicos/farmacología , Línea Celular Tumoral , Dimerización , Humanos , Estructura Molecular , Propano , Análisis Espectral
18.
Nat Prod Res ; 32(14): 1669-1675, 2018 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-29115146

RESUMEN

A new 12,17-cyclo-labdane diterpenoid, podoimbricatin C (1), along with 15 known compounds was isolated from the twigs of Dacrycarpus imbricatus. Their structures were elucidated by means of extensive spectroscopic analysis. Compound 1 is the second example of the unusual 12,17-cyclo-labdane diterpenoids. It showed no inhibitory effects against five human tumour lines (HL-60, SMMC-7721, A-549, MCF-7 and SW-480).


Asunto(s)
Antineoplásicos Fitogénicos/química , Antineoplásicos Fitogénicos/farmacología , Diterpenos/química , Tracheophyta/química , Línea Celular Tumoral , Ensayos de Selección de Medicamentos Antitumorales , Células HL-60 , Humanos , Células MCF-7 , Espectroscopía de Resonancia Magnética , Estructura Molecular
19.
Nat Prod Res ; 32(14): 1699-1705, 2018 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-29092642

RESUMEN

A new (propylphenyl)bibenzyl derivative, dendrowillol A (1), along with 22 known compounds were isolated from the whole plants of Dendrobium williamsonii. Their structures were elucidated by means of extensive spectroscopic analysis. Cytotoxicity evaluation against five human tumour lines showed that all the compounds tested displayed very weak cytotoxicity when compared with the positive control taxol, but selective inhibitory effects on HL-60 for several compounds tested were observed, with IC50 values ranging from 4.48 to 11.04 µM.


Asunto(s)
Antineoplásicos Fitogénicos/farmacología , Bibencilos/farmacología , Dendrobium/química , Antineoplásicos Fitogénicos/química , Compuestos de Bencilo/farmacología , Bibencilos/química , Línea Celular Tumoral , Ensayos de Selección de Medicamentos Antitumorales , Células HL-60 , Humanos , Concentración 50 Inhibidora , Lignanos/química , Lignanos/farmacología , Espectroscopía de Resonancia Magnética , Estructura Molecular
20.
Nat Prod Res ; 32(20): 2447-2451, 2018 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-29284299

RESUMEN

A new phenanthrene, bobulretin A (1), and a new 9,10-dihydrophenanthrene, bobulretin B (2) along with four known bibenzyls (3-6) were isolated from the whole plants of Bulbophyllum retusiusculum. Their structures were elucidated by means of extensive spectroscopic analysis. Bobulretin B (2), isolated as enantiomer mixture with unequal proportions, was verified by analysis on a chiral OD-H HPLC column. Compounds 1, 3 and 4 were evaluated for their α-glucosidase inhibitory activity. Neither of them showed obvious activity.


Asunto(s)
Orchidaceae/química , Fenantrenos/química , Bibencilos/química , Bibencilos/aislamiento & purificación , China , Estructura Molecular , Fenantrenos/aislamiento & purificación , alfa-Glucosidasas
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