Stilbenoids from Pleione bulbocodioides

From tubers of Pleione bulbocodioides, three novel stilbenoids, one a (bibenzyldihydrophenanthrene) ether, one a dihydrophenanthrene and one a bibenzyl, were isolated together with lusianthridin, coelonin, and 2,7-dihydroxy-1-(p-hydroxybenzyl)-4-methoxy-9,10-dihydrophenanthrene. The novel compounds, named shancilin, shancidin and shanciguol, were shown to be 7-O-[4'-(3',3 ''-dihydroxy-5'-methoxybibenzyl)]-4-hydroxy-2-methoxy-9,10-dihydrophenanthrene,4,7-dihydroxy-1-(p-hydroxybenzyl)-2-methoxy-9,10-dihydrophenanthrene and 2,6-bis(p-hydroxybenzyl)-3,3',5-trihydroxybibenzyl, respectively, by their spectroscopic data. One of them, shancilin, having an ether linkage between the dihydrophenanthrene and bibenzyl is the first member of a novel group of stilbenoids.