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1.
Molecules ; 27(9)2022 Apr 30.
Artigo em Inglês | MEDLINE | ID: mdl-35566241

RESUMO

Six new diterpenoids, blusamiferoids A-F (1-6), including four pimarane-type diterpenoids, one rosane-type diterpenoid (3), and one rearranged abietane-type diterpenoid (6), were isolated from the dry aerial parts of Blumea balsamifera. Their structures were characterized by spectroscopic and computational methods. In particular, the structures of 1 and 4 were confirmed by X-ray crystallography. Compounds 5 and 6 were found to dose-dependently inhibit the production of TNF-α, IL-6, and nitrite oxide, and compound 5 also downregulated NF-κB phosphorylation in lipopolysaccharide (LPS)-induced RAW 264.7 cells.


Assuntos
Asteraceae , Diterpenos , Abietanos/química , Abietanos/farmacologia , Animais , Anti-Inflamatórios/química , Anti-Inflamatórios/farmacologia , Asteraceae/química , Diterpenos/química , Diterpenos/farmacologia , Lipopolissacarídeos/farmacologia , Camundongos , Estrutura Molecular , Óxido Nítrico , Células RAW 264.7
2.
Chem Biodivers ; 18(8): e2100231, 2021 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-34087032

RESUMO

Meyeniines A-C (1-3), three new lignans, two known neolignans (4-5), and three known lignans (6-8) were isolated from the rhizomes of Lepidium meyenii. Their structures were identified by comprehensive spectroscopic analyses and computational methods. Compound 1 represents a unique lignan featuring an aromatic ring migration. Compounds 2 and 4-6 were analyzed by chiral HPLC column as enantiomers. Biological evaluation revealed that compound 8 could inhibit IL-6 production in lipopolysaccharide (LPS) induced RAW264.7 cells in a dose-dependent manner.


Assuntos
Anti-Inflamatórios/química , Lepidium/metabolismo , Lignanas/química , Animais , Anti-Inflamatórios/isolamento & purificação , Anti-Inflamatórios/farmacologia , Sobrevivência Celular/efeitos dos fármacos , Interleucina-6/metabolismo , Lignanas/isolamento & purificação , Lignanas/farmacologia , Lipopolissacarídeos/farmacologia , Macrófagos/citologia , Macrófagos/efeitos dos fármacos , Macrófagos/metabolismo , Espectroscopia de Ressonância Magnética , Camundongos , Conformação Molecular , Extratos Vegetais/química , Células RAW 264.7
3.
Molecules ; 26(12)2021 Jun 09.
Artigo em Inglês | MEDLINE | ID: mdl-34207872

RESUMO

Five new compounds including three pairs of enantiomeric xanthine analogues, parvaxanthines D-F (1-3), two new guanosine derivatives, asponguanosines C and D (6 and 7), along with two known adenine derivatives were isolated from the insect Cyclopelta parva. Racemic 1-3 were further separated by chiral HPLC. Their absolute configurations were assigned by spectroscopic and computational methods. It is interesting that all of these isolates are natural product hybrids. Antiviral, immunosuppressive, antitumor and anti-inflammatory properties of all the isolates were evaluated.


Assuntos
Anti-Inflamatórios/farmacologia , Antineoplásicos/farmacologia , Antivirais/farmacologia , Produtos Biológicos/farmacologia , Guanosina/química , Insetos/química , Xantinas/química , Animais , Produtos Biológicos/química , Células Cultivadas , Chlorocebus aethiops , Cromatografia Líquida de Alta Pressão/métodos , Camundongos , Camundongos Endogâmicos C57BL , Estrutura Molecular , Estereoisomerismo
4.
Nano Lett ; 16(1): 519-27, 2016 Jan 13.
Artigo em Inglês | MEDLINE | ID: mdl-26713782

RESUMO

Lithium-sulfur (Li-S) battery system is endowed with tremendous energy density, resulting from the complex sulfur electrochemistry involving multielectron redox reactions and phase transformations. Originated from the slow redox kinetics of polysulfide intermediates, the flood of polysulfides in the batteries during cycling induced low sulfur utilization, severe polarization, low energy efficiency, deteriorated polysulfide shuttle, and short cycling life. Herein, sulfiphilic cobalt disulfide (CoS2) was incorporated into carbon/sulfur cathodes, introducing strong interaction between lithium polysulfides and CoS2 under working conditions. The interfaces between CoS2 and electrolyte served as strong adsorption and activation sites for polar polysulfides and therefore accelerated redox reactions of polysulfides. The high polysulfide reactivity not only guaranteed effective polarization mitigation and promoted energy efficiency by 10% but also promised high discharge capacity and stable cycling performance during 2000 cycles. A slow capacity decay rate of 0.034%/cycle at 2.0 C and a high initial capacity of 1368 mAh g(-1) at 0.5 C were achieved. Since the propelling redox reaction is not limited to Li-S system, we foresee the reported strategy herein can be applied in other high-power devices through the systems with controllable redox reactions.

5.
Phytochemistry ; 199: 113184, 2022 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-35405148

RESUMO

Five undescribed benzopyran containing meroterpenoids, ganodercins Q-U, two undescribed benzofuran containing meroterpenoids, ganodercins V and W, and two known meroterpenoids were isolated from Ganoderma cochlear. Their structures were elucidated by using HRESIMS, NMR spectroscopy and computational methods. The results of biochemical studies using a palmitic acid (PA) induced insulin resistance (IR) model show that (-)-ganodercin Q, (+)-ganodercins R and W activate phospho-AKT (p-AKT) at 20 µM and improve glucose uptake in a concentration dependent manner. The results of renoprotection studies show that (+)-ganodercin S, cochlearol F, (+)- and (-)-ganodercins V reduce the expression of collagen I.


Assuntos
Benzofuranos , Ganoderma , Benzofuranos/farmacologia , Benzopiranos , Ganoderma/química , Estrutura Molecular , Proteínas Proto-Oncogênicas c-akt , Terpenos/química , Terpenos/farmacologia
6.
Phytochemistry ; 202: 113324, 2022 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-35931232

RESUMO

Ganoderma mushrooms are a renowned Chinese medicine and functional food used worldwide. Seven undescribed spiro Ganoderma meroterpenoids spiroganodermaines A-G were isolated from Ganoderma species. Their structures were characterized by using spectroscopic, computational and X-ray diffraction methods. Biological studies showed that (+)-spiroganodermaine G significantly activates glucose uptake and IRS1 phosphorylation in insulin resistance C2C12 cells. Furthermore, (-)-spiroganodermaine G inhibits the expressions of fibronectin and α-SMA in TGF-ß1 induced NRK-52E cells. These findings demonstrate the potential of Ganoderma meroterpenoids as medicines and dietary supplements.


Assuntos
Ganoderma , Resistência à Insulina , Fibrose , Ganoderma/química
7.
Org Lett ; 23(22): 8657-8661, 2021 11 19.
Artigo em Inglês | MEDLINE | ID: mdl-34794314

RESUMO

Populusene A (1), an unprecedented carbon skeleton featuring a bicyclo[8.4.1]pentadecane nucleus and a bridgehead double bond (anti-Bredt system), and populusin A (2), a cembrane-type diterpenoid possessing an uncommon dioxatricyclo[6.6.1.12,5]hexadecane scaffold, were isolated from the exudates of Populus euphratica. Their structures were elucidated by spectroscopic, computational, and crystallographic methods. A plausible biosynthetic route for 1 and 2 was proposed. Compounds 1 and 2 were found to significantly inhibit the production of TNF-α and IL-6 and the expression of iNOS, COX-2, and p-NF-κB at 125 nM in RAW264.7 cells.


Assuntos
Alcanos
8.
Front Chem ; 9: 772740, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34805099

RESUMO

Ganoderma fungi as popular raw materials of numerous functional foods have been extensively investigated. In this study, five pairs of meroterpenoid enantiomers beyond well-known triterpenoids and polysaccharides, dayaolingzhiols I-M (1-5), were characterized from Ganoderma lucidum. Their structures were identified using spectroscopic and computational methods. Structurally, compound 1 features a novel dioxabicyclo[2.2.2]octan-3-one motif in the side chain. Ethnoknowledge-derived biological evaluation found that (+)-5 could activate Akt and AMPK phosphorylation in insulin-stimulated C2C12 cells, and (+)-5 could activate glucose uptake dose dependently in C2C12 cells. Furthermore, we found that (+)-1 (+)-4, and (-)-4 could significantly inhibit cell migration of the MDA-MB-231 cell line, of which (+)-4 showed significant inhibitory effects against cell migration of the MDA-MB-231 cell line in a dose-dependent manner. These findings revealed the meroterpenoidal composition of G. lucidum and its roles in the prevention of chronic diseases such as diabetes mellitus and triple-negative breast cancer.

9.
Fitoterapia ; 151: 104904, 2021 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-33813000

RESUMO

Five new compounds (xuejieins A-E), including three new phenolic glycosides (1, 2, and 5) and two new flavonoids (10 and 11), together with six known compounds were isolated from the resins of Dracaena cochinchinensis (Chinese dragon's blood). The structures of the new compounds were confirmed by extensive spectroscopic methods and electronic circular dichroism (ECD) data analysis. Especially, the absolute configurations of the sugar moieties in compounds 1, 2, and 5 were clarified by GC analysis after acid hydrolysis. All isolated compounds have been tested for antifungal and wound healing promoting activities, The results showed that compound 9 shows significant antifungal activities against Botrytis cinerea, Magnaporthe grisea, Penicillium digitatum, and Sclerotinia sclerotiorum. In addition, compound 4 could significantly stimulate human keratinocytes (HaCAT) proliferation, mobility, and human umbilical vein vascular endothelial cells (HUVECs) tube formation at 40 µM.


Assuntos
Antifúngicos/farmacologia , Dracaena/química , Resinas Vegetais/química , Cicatrização , Antifúngicos/isolamento & purificação , China , Flavonoides/isolamento & purificação , Flavonoides/farmacologia , Glicosídeos/isolamento & purificação , Glicosídeos/farmacologia , Células HaCaT , Células Endoteliais da Veia Umbilical Humana , Humanos , Estrutura Molecular , Compostos Fitoquímicos/isolamento & purificação , Compostos Fitoquímicos/farmacologia , Extratos Vegetais
10.
Adv Sci (Weinh) ; 3(1): 1500268, 2016 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-27774384

RESUMO

Owing to the conversion chemistry of the sulfur cathode, the lithium-sulfur (Li-S) batteries exhibit high theoretical energy density. However, the intrinsic mobile redox centers during the sulfur/Li2S-to-lithium polysulfides solid-to-liquid phase transition induce low sulfur utilization and poor cycling life. Herein, the Janus separator of mesoporous cellular graphene framework (CGF)/polypropylene membrane to promote the utilization of sulfur cathode is introduced. The porous polypropylene membrane serves as an insulating substrate in contact with lithium anode while CGFs that possess high electrical conductivity of 100 S cm-1, a large mesopore volume of 3.1 cm3 g-1, and a huge surface area of 2120 m2 g-1 are adhered on cathode side to reactivate the shuttling-back polysulfides and to preserve the ion channels. Therefore, the Li-S cell with the "two-face" CGF Janus separator exhibit a high initial capacity of 1109 mAh g-1 and superior capacity preserved upon 800 mAh g-1 after 250 cycles at 0.2 C, which is 40% higher on sulfur utilization efficiency than the corresponding results with routine polypropylene separators. There are significant improvements on capacity as well as electrochemical kinetics. A very high areal capacity of 5.5 mAh cm-2 combined with high sulfur content of 80% and areal loading amount of 5.3 mg cm-2 is achieved for such advanced configuration. The negative impact of shuttle mechanism on lowering the utilization of sulfur and overall energy density of a Li-S battery is well eliminated by applying CGF separators. Consequently, employing carbonaceous materials as Janus face of separators enlightens new opportunities for improving the utilization of active materials and energy density of devices that involve complex phase evolution and conversion electrochemistry.

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