| In our continuous efforts on the screening of biologically active agents from sea, the ethanol extract of marine sponge Phyllospongia dendyi presented strong inhibitory bioactivity on the maturation of starfish oocyte Asterian pectinifera, an assay developed for the search of G2/M inhibitors. The bioassay-guided separation resulted in the isolation of 11 polybrominated diphenyl ethers. Their structures were established as ( new compounds were indicated with the asterisk.): 2-(2', 4'-dibromophenoxy)-4, 6-dibromophenol (1), 2-(3', 5'-dibromo-2'- methoxyphenoxy ) -3, 5-dibromoanisole (2), 2-(4', 6'-dibromo-2'-methoxyphenoxy)-3, 5-dibromophenol (3), 2-(4', 5', 6'-tribromo-2'-methoxyphenoxy)-4, 6-dibromoanisole (4), 2-(3', 4', 6'-tribromo-2'-methoxyphenoxy)-4, 6-dibromophenol (5), 2-(3', 4', 5', 6'-tetrabromo-2' -methoxyphenoxy)-4, 6-dibromophenol (6) *, 2-(4', 6'-dibromo-2'-methoxyphenoxy) -4, 6-dibromophenol (7), 2-(4', 5', 6'-dibromo-2'-methoxyphenoxy ) -4, 6-dibromo phenol (8) *, 2-(3', 4', 6'-tribromo-2'-hydroxyphenoxy)-4, 6-dibromophenol (9), 2-(4', 5', 6'-tribromo-2'-hydroxyphenoxy)-3, 5-dibromophenol (10) , 2-(3', 4', 5', 6'-tetra bromo-2'-hydroxyphenoxy)-4, 6-dibromphenol(11) by NMR spectra analysis and comparison with the reference data.The G2/M cell cycle inhibitory activity of compounds 1-11 on first meiotic division of starfish oocytes was evaluated. Compounds 9, 10, and 11 showed inhibitory activity on meiotic maturation of starfish oocytes (G2/M arrest) with the IC50 value of 4.2, 4.2, and 3.6 uM, the integrate germinal vesicles were observed under microscope. On the same time, compounds 9, 10 and 11 presented a promising inhibitory activity on microtubulin polymerization in vitro. IC50 value was determinedas 33.5, 20.9, and 29.6 uM, respectively. It seems that compounds 9, 10, and 11 inhibit the maturation of starfish oocytes via the inhibition of microtubulin polymerization. It is the first report of above-mentioned biological activities for the polybrominated diphenyl ethers. Based on the above bioactivities study, the structure-activity relationship information was obtained.As a part of our continuous study on the anti-cancer components from plants ofDioscorea genus, the ethanol extract of Dioscorea futschauensis Uline ex R. Kunth was under bioassay-guided isolation, using a Pyricularia oryzae bioassay. 28 compounds were isolated from the n-butanol soluble fraction. Their structures were elucidated on the basis of physico-chemical and NMR spectral methods as (new compounds were indicated with asterisk.): p-sitosterol (1), p-daucosterone(2), diogenin(3), Dioscorone A (4)*, 3-phenyl-6, 8-dihydroxydihydroisocoumarin(5)*, diosgenin-3-O-(3-D-glucopyranoside(6), prosapogenin A of dioscin(7), prosapogenin B of dioscin(8), dioscin (9), gracillin (10), (25S)-spirost-5-en-3p, 27-diol-3-O-[a-L-rhamnopyranosyl(1-2)-B-D-glucopyranosyl(1-3)]-B-D-glucopyranoside (dioscoreside F, 11)*, 26-O-B-D-glucopyranosyl-3p, 26-dihydroxy-25 (R)-furosta-5, 20(22)-dien-3-O-a-L-rhamnopyranosyl(1-2)-p-D-glucopyranoside (12), pseudoprotodioscin (13), pseudoprotogracillin (14) *, dioscoreside C (15), 26-Op-D-glucopyranosyl-3p, 26-dmydroxy-23(S)-methoxyl-25(R)-furosta-5, 20(22)-dien-3-O-a-L-rhamnopyranosyl (1-2)-[p-D-glucopyranosyl(1-3)]-B-D-glucopyranoside (dioscoreside E, 16)*, protodioscin (17), methyl protodioscin (18), protoneodioscin (19), methyl protoneodioscin (20), protogracillin (21), methyl protogracillin (22), protoneogracillin (23), methyl protoneogracillin (24), 3p- [(O-a-L-rhamnopyranosyl -(1-2)-O-[a-L-rhamnopyranosyl-(1-4)]-B-D-glucopyranosyl)oxy]pregn-5, 16-en-20-one(hypoglaucin F, 25), 3B-[(O-a-L-rhamnopyranosyl-(1-2)-O-[a-L-glucopyranosyl-(1-3)]-B-D-glucopyranosyl)oxy]pregn-5, 16-en-20-one (26), 16a-methoxyl-3p-[(O-a-L-rhamnopyranosyl-(1-2)-O-[a-L- rhamnopyranosyl-(1-4)]-B-D-glucopyrano syl)oxy]pregn-5-en-20-one (27) * , 21-methoxyl-3B-[(O-a-L-rhamnopyranosyl-(1-2)-O-[a-L-rhamnopyranoyl-(1-4)]-B-D-glucopyranosyl) oxy]pregn-5,16-en-20-one (28) *.The anti-fungal activity and cytotoxicity on K562 ce... |
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