The constituents of Scirpus fluviatilis(Torr). A. Gray. I. The structures of two new hydroxystilbene dimers, scirpusin A and B.

Constituents of Stem Bark of Callistemon rigidus Showing Inhibitory Effects on Mouse .ALPHA.-Amylase Activity

“…Compound 2, isolated as a dark brownish amorphous powder, was concluded to be scirpusin B, a constituent of Scirpus fluviatilis, based on comparison of the various spectral data with those in the literature. 13,14) Since nuclear Overhauser effects were observed between each dihydrofuran ring proton (d 4.38, 5.32) and ortho position protons (d 6.19, 6.67, 6.79) on both benzene rings joined with the dihydrofuran ring carbons bearing each dihydrofuran ring proton, 2 was speculated to be trans-type scirpusin B. Moreover, 2 was presumed to be racemate ([a] D 0.0°).…”

(−)-ε-Viniferin and Related Oligostilbenes fromCarex pumitaThunb. (Gyperaceae)

“…Dehydrogenation of 5a with 2,3-dichloro-5,6-dicyano-p-benzoquinone (DDQ) readily afforded a benzofuran derivative (6). Catalytic hydrogenation of 6 gave a cis-dihydrobenzofuran (7). cis-trans Isomerization at the 7a,8a positions of 7 was smoothly catalyzed by aluminum chloride to yield a corresponding trans isomer (8 * To whom inquiries should be addressed.…”

Isolation and identification of polyphenols from Marsilea quadrifolia with antioxidant properties in vitro and in vivo

“…We reported herein the isolation, structural elucidation and antioxidant activities of the isolated compounds. (±)-(E)-cyperusphenol A (15, a racemate) , mesocyperusphenol A (16) ) and (±)-(E)-scirpusin A (17, a racemate) (Nakajima et al 1978;Ito, Endo, Shinohara, et al 2012) (Figure 1), by comparing their spectroscopic and physical data with those previously reported in the literatures. Detailed structural elucidations of the four new compounds (1, 3, 4, 18) are available in supplementary materials.…”