Description
Glycitein is an O-
methylated isoflavone that comprises 5-
10% of the total isoflavones in soy food products. This phytoestrogen is reported to have weak estrogenic activity, displacing estradiol binding at the estrogen receptor
in vitro with an IC
50 value of 3.94 μM. It suppresses the proliferation of osteoblasts and promotes differentiation from its progenitor. It has also been used to attenuate proliferation (10 μM) of aortic smooth muscle cells related to atherosclerotic vascular change in stroke-
prone hypertensive rats and to protect against beta amyloid (Aβ)-
induced toxicity and oxidative stress (100 μg/ml) in
C. elegans expressing human Aβ.
Synthesis
Under nitrogen protection, boron trifluoride ethyl ether complex (1.6 mL, 13.13 mmol) was slowly added to an anhydrous N,N-dimethylformamide (10 mL) solution of deoxybenzene coupling (0.6 g, 2.19 mmol). After 15 min of reaction, anhydrous N,N-dimethylformamide (2 mL) solution of methanesulfonyl chloride (0.84 mL, 10.95 mmol) was added dropwise. The reaction mixture was heated and stirred in an oil bath at 70°C for 5 hours. Upon completion of the reaction, the mixture was cooled to room temperature and slowly poured into ice-cooled saturated aqueous sodium acetate solution (50 mL). The precipitated solid was collected by filtration and recrystallized from 70% ethanol to afford 7-hydroxy-3-(4-hydroxyphenyl)-6-methoxy-4H-benzopyran-4-one as a yellow solid (0.53 g, 85% yield) with a melting point of 336-338°C. The product structure was determined by 1H NMR. The structure of the product was confirmed by 1H NMR (300 MHz, DMSO-d6) and mass spectrometry (EI, 70 eV): 1H NMR δ 10.63 (br s, 1H, 7-OH), 9.54 (br s, 1H, 4'-OH), 8.27 (s, 1H, H-2), 7.41 (s, 1H, H-5), 7.37 (d, J = 8.7 Hz. 2H, H-2', 6'), 6.92 (s, 1H, H-8), 6.79 (d, J = 8.7 Hz, 2H, H-3', 5'), 3.86 (s, 3H, OCH3); mass spectra m/z 284 (M+, 24%), 283 (100), 268 (15), 255 (20), 212 (41), 171 (15).
