Anticyanobacterial phenolic constituents from the aerial parts of Eupatorium fortunei Turcz.

Four thymol derivatives and two phenolic compounds were isolated from the aerial parts of Eupatorium fortunei. The new structures were elucidated to be 7,8,9-trihydroxythymol (1), and 8,10-didehydro-7,9-dihydroxythymol (2) by means of MS and NMR analysis. The known compounds were identified as 8,9,10-trihydroxythymol (3), 10-acetoxy-8,9-dihydroxythymol (4), o-coumaric acid (5) and 4-(2-hydroxyethyl)benzaldehyde (6).

Balanochalcone, a new chalcone from Balanophora laxiflora Hemsl.

A new chalcone named as balanochalcone (1) together with eight known compounds, methyl caffeate (2), β-hydroxydihydrochalcone (3), methyl gallate (4), dimethyl-6,9,10-trihydroxybenzo[kl]xanthene-1,2-dicarboxylate (5), p-coumaric acid (6), quercetin (7), scopoletin (8) and pinoresinol (9) have been isolated from the ethyl acetate extract of Vietnamese Balanophora laxiflora Hemsl. Their structures were characterised by IR, UV, HR-ESI-MS, 1D and 2D NMR and CD spectroscopies. Compounds 2 and 5 showed moderate cytotoxicity against four cancer cell lines, KB (a human epidermal carcinoma), MCF7 (human breast carcinoma), SK-LU-1 (human lung carcinoma) and HepG2 (hepatocellular carcinoma).

Stemofurans X-Y from the roots of Stemona species from Laos.

Two new phenylbenzofuran-type stilbenoids named stemofurans X and Y (1, 2) were isolated from the roots of Stemona pierrei and S. tuberosa, respectively, together with ten known compounds. These compounds were stemanthrenes B-C (3, 4), (+)-syringaresinol (5), maistemonine (6), isomaistemonine (7) and sesamin (8) from S.

Two new N-oxide alkaloids from Stemona cochinchinensis.

Two new N-oxide alkaloids with pyrrolo[1,2-α]azepine skeleton, namely isoneostemocochinine-N-oxide (1) and neostemocochinine-N-oxide (2), as well as three known alkaloids with pyrido[1,2-α]azepine skeletons, were isolated and identified from the roots of Stemona cochinchinensis (Stemonaceae). The structures of these compounds were elucidated by 1D- and 2D-NMR spectra and other spectroscopic studies. Additionally, the 1H- and 13C-NMR characteristic of N-oxide Stemona alkaloids was summarized.

Three new phenanthrenes, a new stilbenoid isolated from the roots of Stemona tuberosa Lour. and their cytotoxicity.

Three new phenanthrenes, stemophenanthrenes A-C (1-3), along with one new stilbenoid, isopinosylvin A (4) and a known compound methyl ferulate (5), were isolated and identified from the roots of Stemona tuberosa Lour. plants, collected in Attapu province (Laos). Their structures were elucidated by spectroscopic analysis (FT-ICR-MS, IR, UV, 1D and 2D NMR).

Main constituents from the seeds of Vietnamese Cnidium monnieri and cytotoxic activity.

From the ethyl acetate extract of the seeds of Vietnamese Cnidium monnieri L., three coumarins, osthole (1), xanthotoxin (2), imperatorin (3) and a sterol, daucosterol (4) have been purified. Their structures were elucidated by spectroscopic analysis.

Bisbenzopyrans and alkaloids from the roots of Stemona cochinchinensis.

Two new bisbenzopyrans, namely 3,3'-bis(3,4-dihydro-4-hydroxy-6,8-dimethoxy-2H-1-benzopyran) (1), and 8'-methoxy-3,3'-bis(3,4-dihydro-4-hydroxy-6-methoxy-2H-1-benzopyran) (2), together with known 3,3'-bis(3,4-dihydro-4-hydroxy-6-methoxy-2H-1-benzopyran) (3), as well as three known pyrido[1,2-alpha]azapine alkaloids, stemokerrin (4), oxystemokerrin (5) and oxystemokerrin-N-oxide (6), were isolated and identified from the roots of Stemona cochinchinensis. The structures of these compounds were elucidated by 1D- and 2D-NMR spectra and other spectroscopic studies.

Alkaloids from the roots of Stemona saxorum.

Five new Stemona alkaloids, cochinchistemoninone (1), stemokerrin-N-oxide (2), oxystemokerrilactone (3), saxorumamide (4a), and isosaxorumamide (4b), as well as 12 known compounds, were isolated from the roots of Vietnamese Stemona saxorum. The structures of these alkaloids were characterized on the basis of spectroscopic methods.

Alkaloids from Stemona collinsae.

A new alkaloid, isostenine (1), together with two known ones neotuberostemonine (2) and bisdehydroneotuberostemonine (3) were isolated from the root of Stemona collinsae. Their structures were determined by various spectral methods.