Chemical constituents in water fraction of Cynanchum auriculatum / 中草药

ABSTRACT

Objective To investigate the chemical constituents of Cynanchum auriculatum. Methods Compounds were isolated and purified by using a combination of various chromatographic techniques including D-101 macroporous adsorptive resins, silica gel, Sephadex LH-20, and other methods. Their structures were elucidated by MS, NMR, and other modern spectroscopies. Results Fifteen compounds were isolated and identified as isocopoletin (1), isofraxidin (2), deacetylmetaplexigenin (3), vomifoliol (4), 4,4-dimethyl heptanedioic acid (5), (+)-isolariciresinol (6), 3-hydroxypyridine (7), 3-hydroxy-2-methylpyridine (8), 5-hydroxyl-2-hydroxymethylpyridine (9), 2-methyl-6-(2’,3’,4’-trihydroxybutyl)-pyrazine (10), kiwiionol (11), picein (12), adenosine (13), cynanoneside B (14), and cynanoneside A (15). Conclusion Compounds 1-2, 4-13 are isolated from the plants of genus Cynanchum Linn for the first time, while compound 15 is firstly obtained from C. auriculatum.