Triterpene saponins from four species of the polygalaceae family

Twelve triterpene saponins were isolated by successive M PLC over silica gel from four species of Polygalaceae: From Polygala ruwenzoriensis, five new saponins 1-5 of which 1-4 as two pairs of (E)/(Z)-isomers, together with the four known compounds tenuifoline, (E)- and (Z)-senegasaponin b, (E)- and (Z)-senegin II, and polygalasaponin XXVIII, from the genus Carpolobia. one new saponin 6 from C alba and the known arillo-side (11) from C. lutea, and another new triterpene glycoside 7 from Polygala arenaria. Their structures were established mainly by 600-MHz 2D-NMR techniques (H-1,H-1-COSY, TOCSY, NOESY, HSQC, HMBC) as 3-O-(beta-D-glucopyranosyl)presenegenin 28-[O-alpha-L-arabinopyranosyl-(1 -> 4)-O-beta-D-xylopyranosyl-(1 -> 4)-O-alpha-L-rhamnopyranosyl-(1 -> 2)-4-O-[(E)-4-methoxycinnamoyl]-beta-D-fucopyranosyl] ester (1) and its (Z)-isomer 2, 3-O-(beta-D-glucopyranosyl)presenegenin 28-[O-alpha-L-arabinopyranosyl-(1 -> 4)-O-beta-D-xylopyranosyl-(1 -> 4)-O-alpha-L-rhamnopyranosyl-(1 -> 2)-4-O-[(E)-3,4-dimethoxycinnamoyl]-beta-D-fucopyranosyl] ester (3) and its (Z)-isomer 4, 3-O-(beta-D-glucopyranosyl)presenegenin 28-[O-beta-D-galactopyranosyl-(1 -> 4)-O-beta-D-xylopyranosyl-(1 -> 4)-O-alpha-L-rhamnopyranosyl-(1 -> 2)-beta-D-fucopyranosyl] ester (5), 3-O-(beta-D-glucopyranosyl)presenegenin 28-[O-alpha-L-arabinopyranosyl-(1 -> 3)-O-[beta-D-galactopyranosyl-(1 -> 4)]-O-beta-D-xylopyranosyl-(1 -> 4)-O-alpha-L-rhamnopyranosyl-(1 -> 2)-O-[beta-D-apiofuranosyl-(1 -> 3)]-4-O-acetyl-beta-D-fucopyranosyl] ester (6), and 3-O-(beta-D-glucopyranosyl)presenegenin 28-[O-beta-D-galactopyranosyl-(1 -> 4)-O-[beta-D-glucopyranosyl-(1 -> 3)]-O-beta-D-xylo-pyranosyl-(1 -> 4)-O-alpha-L-rhamnopyranosyl-(1 -> 2)-beta-D-fucopyranosyl] ester (7) (presenegenin = (2 beta, 3 beta, 4 alpha)-2,3,27-trihydroxyolean-12-ene-23,28-dioic acid). acid).