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1.
Six flavonoids, five of them novel, have been isolated from the whole stem of Popowia cauliflora and identified as: baicalein trimethyl ether, 5-hydroxy-6,7-dimethoxyflavone, 5,7,8-trimethoxyflavanone, 2′-hydroxy-3′,4′,6′-trimethoxychalcone, 2′,3′,4′,6′-tetramethoxychalcone and 2′,4-dihydroxy-3′,4′,6′-trimethoxychalcone, on the basis of spectral data and simple chemical modifications. The value of 13C NMR in assigning the positions of methoxy substituents is briefly discussed. 相似文献
2.
Lara Soares Aleixo de Carvalho Lívia Mara Silva Vinícius Carius de Souza Marcos Paulo Nascimento da Silva Priscila V. S. Z. Capriles Priscila de Faria Pinto Josué de Moraes Ademar Alves Da Silva Filho 《化学与生物多样性》2021,18(11):e2100604
Schistosomiasis, a neglected tropical disease caused by Schistosoma species, harms over 250 million people in several countries. The treatment is achieved with only one drug, praziquantel. Cardamonin, a natural chalcone with in vitro schistosomicidal activity, has not been in vivo evaluated against Schistosoma. In this work, we evaluated the in vivo schistosomicidal activities of cardamonin against Schistosoma mansoni worms and conducted enzymatic apyrase inhibition assay, as well as molecular docking analysis of cardamonin against potato apyrase, S. mansoni NTPDase 1 and S. mansoni NTPDase 2. In a mouse model of schistosomiasis, the oral treatment with cardamonin (400 mg/kg) showed efficacy against S. mansoni, decreasing the total worm load in 46.8 % and reducing in 54.5 % the number of eggs in mice. Cardamonin achieved a significant inhibition of the apyrase activity and the three-dimensional structure of the potato apyrase, obtained by homology modeling, showed that cardamonin may interact mainly through hydrogen bonds. Molecular docking studies corroborate with the action of cardamonin in binding and inhibiting both potato apyrase and S. mansoni NTPDases. 相似文献
3.
Haoran Liu Haoqun Fan Xiaohui Gao Xueqing Huang Xianjun Liu Linbo Liu 《Journal of enzyme inhibition and medicinal chemistry》2016,31(4):580-589
In order to study the structure–activity relationship of Flavokawain B Mannich-based derivatives as acetylcholinesterase (AChE) inhibitors in our recent investigation, 20 new nitrogen-containing chalcone derivatives (4?a–8d) were designed, synthesized, and evaluated for AChE inhibitory activity in vitro. The results suggested that amino alkyl side chain of chalcone dramatically influenced the inhibitory activity against AChE. Among them, compound 6c revealed the strongest AChE inhibitory activity (IC50 value: 0.85?μmol/L) and the highest selectivity against AChE over BuChE (ratio: 35.79). Enzyme kinetic study showed that the inhibition mechanism of compound 6c against AChE was a mixed-type inhibition. The molecular docking assay showed that this compound can both bind with the catalytic site and the peripheral site of AChE. 相似文献
4.
An efficient method for palladium-catalyzed CO cross-coupling of ethyl acetohydroxamate (EAcHO) with 4-bromo-chalcones has been developed to synthesize novel chalcones. The two supporting ligands, namely tBuXPhos (L7), and cataCXium®PIntB (L16) were found to be effective ligands towards the Pd-catalyzed CO cross-coupling reaction to afford the desired product in moderate to excellent yields (50–99%). The coupled products were screened for in vitro blood stage antiplasmodial activity against Plasmodium falciparum (3D7) using the [3H] hypoxanthine incorporation inhibition assay. Of the twenty two compounds screened, eleven showed good antiplasmodial activity with IC50 values ranging from 6–16 μg/mL. The selected active molecules 11, 16, 22, (IC50 12 μg/mL) and 19 (IC50 6 μg/mL) were studied for their cytotoxic effect against HepG2 Cells (human hepatocellular liver carcinoma cell lines), showing the selectivity index (SI) values are greater than 4 except chalcone 22. Our result demonstrates a methodology for synthesizing novel chalcones as a new class of antiplasmodial agent. 相似文献
5.
Bois F Boumendjel A Mariotte AM Conseil G Di Petro A 《Bioorganic & medicinal chemistry》1999,7(12):84-2695
A series of 4-alkoxy-2′,4′,6′-trihydroxychalcones have been synthesized and evaluated for their ability to inhibit P-glycoprotein-mediated multidrug resistance (MDR) by direct binding to a purified protein domain containing an ATP-binding site and a modulator-interacting region. The introduction of hydrophobic alkoxy goups at position 4 led to much more active compounds as compared to the parent chalcone. The binding affinity increased as a function of the chain length, up to the octyloxy derivative for which a KD of 20 nM was obtained. 相似文献
6.
The twigs of Dorstenia barteri var. subtriangularis yielded three diprenylated chalcones: (-)-3-(3,3-dimethylallyl)-5'-(2-hydroxy-3-methylbut-3-enyl)-4,2',4'-trihydroxychalcone, (+)-3-(3,3-dimethylallyl)-4',5'-[2'-(1-hydroxy-1-methylethyl)-dihydrofurano]-4,2'-dihydroxychalcone and 3,4-(6",6"-dimethyldihydropyrano)-4',5'-[2',-(1-hydroxy-1-methylethyl)-dihydrofurano]-2'-hydroxychalcone for which the names bartericins A, B and C, respectively, are proposed. Stipulin, beta-sitosterol and its 3-beta-D-glucopyranosyl derivative were also isolated. The structures of these secondary metabolites were determined on the basis of spectroscopic analysis, especially, NMR spectra in conjunction with 2D experiments, COSY, HMQC and HMBC. The structural relationship of bartericins B and C was further established by the chemical cyclization of one to the other. 相似文献
7.
8.
Helichrysum athrixiifolium afforded in addition to known ones three new prenylated flavanoids, one chalcone and two flavanones. 相似文献
9.
Marvin L. Roberts 《Biochemical Systematics and Ecology》1980,8(2):115-118
A new naturally occurring chalcone glycoside, chalcone, and other chalcones, aurones, flavonols, and anthocyanins are reported from Megalodonta (Bidens) beckii. The plan is an amphibious aquatic with heterophyllous leaves, but the presence of certain flavonoids is correlated with vegetative versus floral tissues rather than vegetative leaf form. The implications of flavonoid chemistry with respect to the relationship of M. beckii to several sections of Bidens are discussed. 相似文献
10.