• Journal of Applied Biological Chemistry
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• 제57권2호
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• pp.175-178
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• 2014

Three phytosterols of rare occurrence, schleicheol 2 (1), $7{\beta}$-hydroxysitosterol (2), and $7{\alpha}$-hydroxysitosterol (3), were isolated from the n-hexane fraction of rice (Oryza sativa) bran, for the first time. Some nuclear magnetic resonance (NMR) assignments in the literatures are inaccurate. This study employed two-dimensional NMR experiments to identify exact peak assignments.

• Journal of Applied Biological Chemistry
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• 제54권4호
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• pp.309-312
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• 2011

Chipped stem wood from Lindera glauca was extracted repeatedly with 80% aqueous methanol at room temperature, and the concentrated methanolic extract was successively partitioned with ethyl acetate (EtOAc), n-butyl alcohol, and $H_2O$. From the EtOAc fraction, four sterols were isolated through a repeated silica gel and octadecyl silica gel column chromatography. The chemical structures of the sterols were elucidated as ${\beta}$-sitosterol (1), 7-ketositosterol (2), 7${\beta}$-hydroxysitosterol (3), and daucosterol (4). Among them, compounds 2 and 3 were isolated for the first time from the stem woods of this plant.

• 생약학회지
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• 제39권3호
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• pp.186-193
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• 2008

Astragali Radix, known as Huangqi, is the most important tonic in the traditional oriental medicine. It reinforces 'qi' (vital energy), strengthens the superficial resistance and promotes the discharge of pus and the growth of new tissue. It has long been used as an anti-perspirant, anti-diuretic or a tonic. Eleven compounds were isolated from the hexane and EtOAc fractions from the roots of Astragalus membranaceus (Leguminosae) and their structures were identified as four triterpenoids [lupenone (1), friedelin (2), lupeol (3), soyasapogenol E (9)] and seven sterols [${\beta}-sitosterol$ (4), stigmastane-3,6-dione (5), $7{\alpha}-hydroxysitosterol$ (6), $5{\alpha},6{\beta}-dihydroxysitosterol$ (7), $7-oxo-{\beta}-sitosterol$ (8), ${\beta}-sitosterol$ glucoside 6'-O-palmitate (10), ${\beta}-sitosterol$ glucoside (11)]. The chemical structures of these compounds were identified on the basis of spectroscopic methods and comparison with literature values. Among these compounds, lupenone (1), friedelin (2), lupeol (3), stigmastane-3,6-dione (5), $7{\alpha}-hydroxysitosterol$ (6), $5{\alpha},6{\beta}-dihydroxysitosterol$ (7), $7-oxo-{\beta}-sitosterol$ (8), soyasapogenol E (9), and ${\beta}-sitosterol$ glucoside 6'-O-palmitate (10) were isolated from this plant for the first time.