Search results for "Chalcones"
showing 6 items of 26 documents
Synthesis and Anti-Tumor Activity of Novel Aminomethylated Derivatives of Isoliquiritigenin
2014
A series of new aminomethylated derivatives of isoliquiritigenin was synthesized. The structures of the compounds were confirmed by IR, MS, NMR, 13C-NMR and elemental analyses. Cytotoxic activities of these derivatives towards the human prostatic cell line PC-3, human mammary cancer cell line MCF-7 and human oophoroma cell line HO-8910 in vitro were tested. The IC50 values showed cytotoxic activities of some of these new derivatives were relatively strong. Furthermore, tumor growth inhibition in vivo of aminomethylated derivatives of isoliquiritigenin 15 was superior to that of isoliquritigenin and reached inhibition rates of 71.68%. The detailed synthesis, spectroscopic data, biological an…
Differential effects of isoliquiritigenin and YC-1 in rat aortic smooth muscle.
1997
We investigated the effects of isoliquiritigenin and YC-1 (3-(5'-hydroxymethyl-2'-furyl)-1-benzyl indazole) on tension in endothelial-free rat aortic rings precontracted with phenylephrine (3 microM). Both compounds induced a concentration-dependent relaxation (EC50 of YC-1 1.9 microM and of isoliquiritigenin 9.4 microM). The effects developed faster with YC-1 than with isoliquiritigenin, and the effects of YC-1 were potentiated by isoliquiritigenin (10 microM). 1H-[1,2,4]Oxadiazolo[4,3-a]quinoxalin-1-one (30 microM) inhibited the effect of YC-1, but not of isoliquiritigenin. These results suggest that the effects of YC-1 are due to stimulation of soluble guanylyl cyclase activity, whereas …
Cardiac effects of isoliquiritigenin
1997
The effects of isoliquiritigenin on force of contraction (Fc), L-type Ca2+ current (I(Ca)) and intracellular Ca2+ concentration ([Ca2+]i) were investigated in rat ventricular heart muscle. Isoliquiritigenin increased Fc and I(Ca) and, after longer exposure times, resting tension and [Ca2+]i. The effect of isoliquiritigenin (100 microM) on I(Ca) was diminished by Rp-cAMPS (30 microM). 1H-[1,2,4]oxa- diazolo[4,3-a]quinoxalin-1-one (50 microM) did not influence the effects of isoliquiritigenin on Fc and I(Ca). The positive inotropic effects of isoprenaline and forskolin, but not of 3-isobutyl-1-methylxanthine, were potentiated by isoliquiritigenin (100 microM). In the presence of milrinone (10…
Dynamic Effects on Reaction Rates in a Michael Addition Catalyzed by Chalcone Isomerase. Beyond the Frozen Environment Approach
2008
We present a detailed microscopic study of the dynamics of the Michael addition reaction leading from 6'-deoxychalcone to the corresponding flavanone. The reaction dynamics are analyzed for both the uncatalyzed reaction in aqueous solution and the reaction catalyzed by Chalcone Isomerase. By means of rare event simulations of trajectories started at the transition state, we have computed the transmission coefficients, obtaining 0.76 +/- 0.04 and 0.87 +/- 0.03, in water and in the enzyme, respectively. According to these simulations, the Michael addition can be seen as a formation of a new intramolecular carbon-oxygen bond accompanied by a charge transfer essentially taking place from the nu…
Some substrates and inhibitors of cytosolic epoxide hydrolase induce sister-chromatid exchanges in mammalian cells, but do not induce gene mutations …
1993
Abstract Trans -stilbene oxide, trans -β-methylstyrene, 7,8-oxide, trans -β-ethylstyrene, 7,8-oxide, trans -β-propylstyrene 7,8-oxide and 4-fluorochalcone oxide were investigated for genotoxic activity in bacterial and mammalian cells, in the absence of external xenobiotic-metabolising systems. All compounds strongly enhanced the frequency of sister-chromatid exchanges (SCE) in cultured human lymphocytes. None of them was mutagenic in Salmonella typhimurium (reversion of the his − strains TA98, TA100 and TA104). The limit of detection was 1 20,000 to 1 10 6 of the activity of the positive control, benzo[ a ]pyrene 4,5-oxide, depending on the compound and the bacterial strain. Trans -β-methy…
Rotenoids, Flavonoids, and Chalcones from the Root Bark of Millettia usaramensis.
2015
Five new compounds, 4-O-geranylisoliquiritigenin (1), 12-dihydrousararotenoid B (2), 12-dihydrousararotenoid C (3), 4'-O-geranyl-7-hydroxyflavanone (4), and 4'-O-geranyl-7-hydroxydihydroflavanol (5), along with 12 known natural products (6-17) were isolated from the CH2Cl2/MeOH (1:1) extract of the root bark of Millettia usaramensis ssp. usaramensis by chromatographic separation. The purified metabolites were identified by NMR spectroscopic and mass spectrometric analyses, whereas their absolute configurations were established on the basis of chiroptical data and in some cases also by X-ray crystallography. The crude extract was moderately active (IC50 = 11.63 μg/mL) against the ER-negative…