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1.
Angew Chem Int Ed Engl ; 62(15): e202300074, 2023 Apr 03.
Artigo em Inglês | MEDLINE | ID: mdl-36781386

RESUMO

Pyrometallurgy technique is usually applied as a pretreatment to enhance the leaching efficiencies in the hydrometallurgy process for recovering valuable metals from spent lithium-ion batteries. However, traditional pyrometallurgy processes are energy and time consuming. Here, we report a carbothermal shock (CTS) method for reducing LiNi0.3 Co0.2 Mn0.5 O2 (NCM325) cathode materials with uniform temperature distribution, high heating and cooling rates, high temperatures, and ultrafast reaction times. Li can be selectively leached through water leaching after CTS process with an efficiency of >90 %. Ni, Co, and Mn are recovered by dilute acid leaching with efficiencies >98 %. The CTS reduction strategy is feasible for various spent cathode materials, including NCM111, NCM523, NCM622, NCM811, LiCoO2 , and LiMn2 O4 . The CTS process, with its low energy consumption and potential scale application, provides an efficient and environmentally friendly way for recovering spent lithium-ion batteries.

2.
J Org Chem ; 86(6): 4786-4793, 2021 03 19.
Artigo em Inglês | MEDLINE | ID: mdl-33719430

RESUMO

Mulberry Diels-Alder-type adducts (MDAAs) are a group of rare natural polyphenols biosynthetically derived from [4 + 2]-cycloaddition of chalcones and dehydroprenylphenols. In this study, kuwanons G (1) and H (2), two bioactive MDAAs with unique dehydroprenylflavonoid dienes, were totally synthesized for the first time in a biomimetic manner. The key features of the convergent route include the use of the Baker-Venkataraman rearrangement, alkylation of ß-diketone, intramolecular cyclization, and Suzuki-Miyaura coupling to achieve the subunit diene.


Assuntos
Chalconas , Morus , Ciclização , Reação de Cicloadição , Frutas
3.
J Nat Prod ; 83(2): 255-267, 2020 02 28.
Artigo em Inglês | MEDLINE | ID: mdl-32003565

RESUMO

The phytochemical investigation of the roots of Croton crassifolius led to the isolation of 16 new halimane furanoditerpenoids, crohalifuranes A-P (1-16), along with 15 known analogues, 17-31. The new structures including their absolute configurations were elucidated by NMR and MS data analysis, comparison of experimental and calculated electronic circular dichroism data, single-crystal X-ray diffraction data, and chemical methods. Crohalifuranes A (1) and B (2) are tetranor- and 19-nor-halimane diterpenoids featuring a rare decahydroacenaphthene core, respectively, which might be derived from the accompanying crassifoliusin A by loss of the furan ring or the C-19 substituent. Crohalifurane C (3) represents the first example of a 20-nor-halimane diterpenoid, and crohalifurane D (4) is characterized by an unusual 6,20-δ-lactone moiety. All compounds were examined for their inhibitory effects on nitric oxide (NO) production induced by lipopolysaccharide in RAW264.7 cells, and 2 and 23 exhibited moderate inhibition on NO production with IC50 values of 17.2 ± 1.3 and 23.7 ± 1.4 µM, respectively.


Assuntos
Croton/química , Diterpenos Clerodânicos/química , Diterpenos/química , Lipopolissacarídeos/química , Óxido Nítrico/análise , Raízes de Plantas/química , Células RAW 264.7/química , Animais , Dicroísmo Circular , Cristalografia por Raios X , Diterpenos/isolamento & purificação , Diterpenos Clerodânicos/isolamento & purificação , Furanos/química , Espectroscopia de Ressonância Magnética , Camundongos , Estrutura Molecular , Óxido Nítrico/química
4.
Bioorg Chem ; 98: 103763, 2020 05.
Artigo em Inglês | MEDLINE | ID: mdl-32200324

RESUMO

Thirteen new jatrophane diterpenoids, euphoresulanes A-M (1-13), and seven known analogues (14-20) were isolated from the whole plants of Euphorbia esula. Their structures were elucidated by extensive spectroscopic analysis, and the absolute configurations of 1, 6, and 10 were confirmed by single crystal X-ray diffraction. Compounds 1-20 were screened for the multidrug resistance (MDR) reversal activity on P-glycoprotein (Pgp)-dependent cancer cell line HepG2/ADR, and 1, 2, 4, 6, and 8 exhibited comparable activity to the positive drugs. Euphoresulane H (8), the most active MDR modulator, could enhance the efficacy of anticancer drug adriamycin to ca. 33 folds at 5 µM. The structure-activity relationship (SAR) study revealed that the acyloxy substitution at C-9 is essential to the activity and presence of H-2 was favorable.


Assuntos
Antineoplásicos Fitogênicos/farmacologia , Diterpenos/farmacologia , Euphorbia/química , Antineoplásicos Fitogênicos/química , Antineoplásicos Fitogênicos/isolamento & purificação , Proliferação de Células/efeitos dos fármacos , Cristalografia por Raios X , Diterpenos/química , Diterpenos/isolamento & purificação , Relação Dose-Resposta a Droga , Resistência a Múltiplos Medicamentos/efeitos dos fármacos , Resistencia a Medicamentos Antineoplásicos/efeitos dos fármacos , Ensaios de Seleção de Medicamentos Antitumorais , Humanos , Modelos Moleculares , Estrutura Molecular , Relação Estrutura-Atividade , Células Tumorais Cultivadas
5.
Nat Prod Res ; 37(1): 31-38, 2023 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-34212817

RESUMO

Natural plant-derived protein with excellent bioactivities has attracted much attention so a functional protein with molecular weight of 15.2 kDa was extracted from Millettia speciosa Champ. leaf for the first time. Under the pH of 12.0, solid-liquid ratio of 1:40 (w/v), extraction time of 2.0 h, and extraction temperature of 50 °C, the highest extracting efficiency (79.25 ± 0.78%) of the Millettia speciosa Champ. leaf protein (MLP) was achieved. The main structure of MLP contained ß-fold and ß-corner by Fourier transform infrared spectroscopy (FTIR) and Circular dichroism (CD) spectra analysis. Additionally, MLP was predominant with glutamic acid, aspartic acid, and leucine, which could be considered as a high quality natural protein. MLP showed great water holding capacity (WHC), oil absorption capacity (OAC), as well as emulsifying and foaming properties. Simultaneously, MLP exhibited considerable antioxidant activity. These results suggested that MLP could be utilised as a promising ingredient of functional foods.


Assuntos
Millettia , Millettia/química , Antioxidantes/química , Proteínas de Plantas/análise , Ácido Aspártico , Folhas de Planta/química
6.
Nat Prod Bioprospect ; 12(1): 31, 2022 Sep 02.
Artigo em Inglês | MEDLINE | ID: mdl-36050566

RESUMO

Mulberry Diels-Alder-type adducts (MDAAs) are unique phenolic natural products biosynthetically derived from the intermolecular [4 + 2]-cycloaddition of dienophiles (mainly chalcones) and dehydroprenylphenol dienes, which are exclusively distributed in moraceous plants. A total of 166 MDAAs with diverse skeletons have been isolated and identified since 1980. Structurally, the classic MDAAs characterized by the chalcone-skeleton dienophiles can be divided into eight groups (Types A - H), while others with non-chalcone dienophiles or some variations of classic MDAAs are non-classic MDAAs (Type I). These compounds have attracted significant attention of natural products and synthetic chemists due to their complex architectures, remarkable biological activities, and synthetic challenges. The present review provides a comprehensive summary of the structural properties, bioactivities, and syntheses of MDAAs. Cited references were collected between 1980 and 2021 from the SciFinder, Web of Science, and China National Knowledge Internet (CNKI).

7.
Fitoterapia ; 143: 104582, 2020 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-32234372

RESUMO

Four new tetracyclic triterpenoids (1-4) were isolated from the leaves and twigs of Jatropha gossypiifolia. Their structures were elucidated by MS and NMR data analysis, together with the Mo2(OAc)4-induced CD data. Jagabeoeuphols A-C (1-3) are rare 19(10 â†’ 9)abeo-euphane-type triterpenoids possessing a Δ5(10) group and a 7,8-epoxide moiety, and jagoseuphone A (4) is a typical euphane-type triterpenoid. The inhibitory effects of 1-4 on nitric oxide production induced by lipopolysaccharide in RAW264.7 cells were evaluated, and 4 exhibited moderate inhibitory activity with an IC50 value of 20.1 µM.


Assuntos
Jatropha/química , Folhas de Planta/química , Triterpenos/farmacologia , Animais , China , Camundongos , Estrutura Molecular , Óxido Nítrico/metabolismo , Compostos Fitoquímicos/isolamento & purificação , Compostos Fitoquímicos/farmacologia , Células RAW 264.7 , Triterpenos/química
8.
Int J Biol Macromol ; 145: 547-557, 2020 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-31891701

RESUMO

A novel polysaccharide fraction (MSCP2) was extracted and isolated from the roots of Millettia Speciosa Champ. Structural characterization revealed that MSCP2 had an average molecular weight of 2.85 × 104 Da and was composed of fucose, arabinose, galactose, glucose and xylose with a ratio of 2.20: 2.52: 4.04: 87.29: 3.96. Methylation analysis and nuclear magnetic resonance (NMR) analysis showed that the main glycosidic linkage types of MSCP2 were proved to be α-D-Glcp-(1→, →4)-α-D-Glcp-(1→, →4)-α-D-Xylp-(1→, →6)-ß-D-Galp-(1→, α-L-Araf-(1→, →3,4)-ß-L-Fucp-(1→ and →4)-α-D-GalpA-(1→. The immunomodulatory assay suggested that MSCP2 could significantly improve the pinocytic capacity and increase the secretion of nitric oxide (NO) and cytokines by regulating the corresponding mRNA expression in RAW 264.7 cells. The data from the membrane receptor assay demonstrated that the potential mechanisms of MSCP2-induced macrophage activation were mainly through toll-like receptor 4 (TLR4), scavenger receptor type A (SRA) and glucan receptor (GR)-mediated signaling pathways. These results suggested that MSCP2 can be developed as a promising immunomodulatory agent in functional foods.


Assuntos
Millettia/química , Polissacarídeos/química , Receptor 4 Toll-Like/genética , Animais , Arabinose/química , Fucose/química , Galactose/química , Regulação da Expressão Gênica/efeitos dos fármacos , Glucanos/genética , Glucose/química , Espectroscopia de Ressonância Magnética , Camundongos , Óxido Nítrico/biossíntese , Óxido Nítrico/química , Raízes de Plantas/química , Polissacarídeos/isolamento & purificação , Polissacarídeos/farmacologia , Células RAW 264.7 , RNA Mensageiro/biossíntese , Receptores Depuradores Classe A/genética , Xilose/química
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