Do Thi Trang

Prenylated isoflavones from Cudrania tricuspidata inhibit NO production in RAW 264.7 macrophages and suppress HL-60 cells proliferation

Abstract Inhibitory effects of NO production in RAW 264.7 macrophages guided the isolation of nine prenylated isoflavones, including a new cudraisoflavone L (1) and eight known metabolites furowanin B (2), erysubin A (3), wighteone (4), lupalbigenin (5), laburnetin (6), isolupalbigenin (7), 6,8-diprenylorobol (8), millewanin H (9) from the leaves of Cudrania tricuspidata. At the concentration of 10 μM, compounds 1, 2, and 4 significantly inhibited NO production with the inhibitory values of 72.5 ± 2.4, 66.9 ± 1.8, and 55.4 ± 2.7%, respectively. In addition, all of isolated compounds 1–9 showed promising cytotoxic effects toward HL-60 cells (IC50 4.3 ± 0.7 to 18.0 ± 1.7 μM).

1)H and (13)C NMR assignments of sesquiterpenes from Dysidea fragilis.

Sesquiterpenes have been reported as components of the genus Dysidea (Dysideidae). Many chemical investigations have been focused on the marine sponge Dysidea fragilis. The constituents of D. fragilis were identified as sesquiterpenes, steroids and diketopiperazines. They exhibited various biological activities such as anti-inflammatory and cytotoxic activities. Previously, series of new sesquiterpenes were reported from the Vietnamese sponge D. cinerea by our group. In continuing research on bioactive compounds from genus Dysidea, three new and two known sesquiterpenes were isolated from the sponge D. fragilis. Herein, we report the isolation and structure elucidation of these compounds.

Flavonoid glycosides from Antidesma ghaesembilla

Four flavone glycosides were isolated from the leaves of Antidesma ghaesembilla. They were elucidated to be vitexin, orientin, isovitexin, and homoorientin by 1D- and 2D-NMR and in comparison with literature data. These compounds have been reported from the genus Antidesma for the first time.

Biflavones and megastigmane glycosides from the leaves of Antidesma bunius.

Two biflavones, podocarpusflavone A ( 1 ) and amentoflavone ( 2 ) and two megastigmane glycosides, byzantionoside B ( 3 ) and (6 S ,9 R )-roseoside ( 4 ) were isolated from the methanol extract of the leaves of Antidesma bunius . Their structures were determined by spectroscopic methods and in comparison with the published data. Keywords. Antidesma bunius, Euphorbiaceae, biflavone, megastigmane.

Furanosesterterpenes from the marine sponge Ircinia echinata (Keller, 1889)

Four furanosesterterpene, (7 E ,12 E ,20 Z ,18 β )-variabilin ( 1 ), (12 E ,20 Z ,18 β )-8-hydroxyvariabilin ( 2 ), (7 E ,11 E ,3 β )-3,7,11-trimethyl-14-(furan-3-yl)tetradec-7,11-dienoic acid ( 3 ), and furoscalarol ( 4 ), and one sterol, 3 β -hydroxycholest-5-en-7-one ( 5 ) were isolated from the methanol extract of the sponge Ircinia echinata (Keller, 1889). Their structures were elucidated by 1D and 2D-NMR spectra and in comparison with those reported in the literature. Keywords . Sponge, Ircinia echinata , furanosesterterpene, sterol.

Cyclopeptide alkaloid and lignans from Antidesma hainanensis Merr.

Cyclopeptide alkaloid lotusanine B ( 1 ) and three lignans (-)-lyoniresinol ( 2 ), (+)-lyoniresinol 3 α - O - β -D-glucopyranoside ( 3 ), and (+)-isolariciresinol 3 α-O-β -D-glucopyranoside ( 4 ) were isolated from the methanol extract of the Antidesma hainanensis leaves. Their chemical structures were successfully determined using NMR and ESI-MS analysis as well as in comparison with the reported data. Especially, the NMR data of lotusanine B were first confirmed by 2D-NMR spectroscopies and reassigned. This is the first report of lotusanine B from Euphorbiaceae family.

Dipeptide and phenolic compounds from the leaves of Cudrania tricuspidata Carr. Bur and their cytotoxic activity

By various chromatographic separations, two peptides, aurantiamide acetate ( 1 ) and aurantiamide ( 2 ), and two phenolic compounds, ( E )- p -coumaric acid ( 3 ) and gatrodin ( 4 ), were isolated from methanol extract of the Cudrania tricuspidata leaves. Their structures were determined by 1D-, 2D-NMR spectra and in comparison with the reported data. Aurantiamide exhibited significant cytotoxic activity on HL-60 leukemia human cancer cell line with IC 50 value of 20.41 mM. Compounds 1 and 2 were reported from genus Cudrania for the first time. Keywords. Cudrania tricuspidata, aurantiamide, aurantiamide acetate.

Quassinoids from Eurycoma longifolia

By various chromatographic separations, three quassinoids, pasakbumin-C ( 1 ), 13 α ,21-epoxyeurycomanone ( 2 ), and eurylactone A ( 3 ) were isolated from the methanol extract of the roots of E. longifolia. Their structures were determined by 1D-NMR, 2D-NMR and in comparison with literature data.