[A new cytotoxic alkaloid from roots of Alangium chinense].

We have carried out the chemical investigation on the roots of Alangium chinense. The chemical constituents from the roots of A.chinense were isolated and purified by various chromatographic techniques, such as silica gel, MCI-Gel resin, Sephadex LH-20 and high performance liquid chromatography. As a result, three alkaloids (1-3) were isolated from 90% EtOH extracts of the roots of this plant. Their structures were elucidated by physical-chemical properties and spectral data. Among them, compound 1 is a new compound, determined as 8-hydroxy-3-hydroxymethyl-6,9-dimethyl-7H-benzo[de]isoquinolin-7-one. Cytotoxicity of the compounds was evaluated by the MTT method. Compound 1 displayed cytotoxicity against NB4, A-549, SHSY5Y, PC-3 and MCF-7 cell lines with IC50 values of 4.2, 3.5, 5.7, 2.8 and 3.9 µmol•L⁻¹, respectively.

Three new anthraquinones from the twigs of Cassia fistula and their bioactivities.

Three previously unreported anthraquinones, fistulaquinones A-C (1-3), together with three known ones (4-6) were isolated from the twigs of Cassia fistula. Their structures were determined by means of extensive NMR and MS spectroscopic analyses. All the isolated compounds were tested for their anti-tobacco mosaic virus (anti-TMV) activity, and compound 3 showed significant activity with inhibition rate of 34.5% at 20 µM concentration, even more potent than positive control. Additionally, compounds 1-6 exhibited moderate cytotoxicity with IC50 values ranging from 2.8 to 9.4 µM for some tested human tumor cell lines.

[A new nor-sesquiterpene from Cassia occidentalis and its bioactivity].

The phytochemistry investigation on the Cassia occidentalis, a Dai Medicine, was carried out. The C. occidentalis was extracted with ethanol and then partitioned with EtOAc. The EtOAc soluble materials were subjected repeatedly to column chromatography on silica gel and preparative RP-HPLC, leading to isolation of a nor-sesquiterpene, 3-isopropyl-1,6-dimethoxy-5-methyl-naphthalen-7-ol (1), and a sesquiterpene, 2,7-dihydroxy-4-isopropyl-6-methyl-naphthalene-1-carbaldehyde (2). Their structures were determined by means of spectroscopic studies. Compound 1 is a new compound. Compound 2 is also isolated from C. occidentalis for the first time. In addition, the cytotoxicity of compound 1 for NB4, A549, SHSY5Y, PC3, and MCF7 cells line was assayed by using the MTT method, and it displayed potential cytotoxicity for the tested cancer cell-line with IC50 valves of (1.8±0.2), (1.2±0.2), (0.9±0.1), (2.2±0.3), (2.6±0.3) µmol•L⁻¹, respectively.

[A new furan-2-carboxylic acid from stem bark of Cassia alata].

A new furan-2-carboxylic acid, 5-[3-(hydroxymethyl)-4,5-dimethoxyphenyl]-3-methylfuran-2-carboxylic acid(1),has been isolated from the bark of Cassia alata by using various chromatographic techniques. It displayed cytotoxicity against NB4, A549, SHSY5Y, PC3 and MCF7 cell lines with IC50 values of 2.5, 1.2, 2.2, 3.6 and 1.9 µmol•L⁻¹, respectively.

[A new sesquiterpene from seeds of Cassia occidentalis and its cytotoxicity].

For the purpose of finding new bioactive agents from ethnic medicines, the chemical study on Dai Medicine Cassia occidentalis was carried out. The chemical constituents from the seeds of C. occidentalis were isolated by column chromatographic methods on silica gel, MCI-Gel resin, Sephadex LH-20, and high performance liquid chromatography. Their structures were elucidated by spectroscopic methods, including extensive 1D and 2D NMR techniques. The cytotoxicity of the compound for NB4, A549, SHSY5Y, PC3, and MCF7 cells line was also assayed by using the MTT method. Two sesquiterpenes (1 and 2) were isolated from this plant. Compound 1 is a new compound and named as methyl 6-(hydroxymethyl)-4-isopropyl-7-methoxynaphthalene-1-carboxylate. Compound 1 also displayed high cytotoxicity with the tested cancer cell-lines.

[A new isoindole alkaloid from leaves of Cassia siamea].

A new isoindole alkaloid (1), has been isolated from the leaves of Cassia siamea by using various chromatographic techniques. Compound 1 is a new compound, determined as 5-(hydroxymethyl)-2-methyl-6-prenylisoindolin-1-one, and it displayed cytotoxicity against NB4, A549, SHSY5Y, PC3 and MCF7 cell lines with IC50 values of 3.2,4.6,2.8,6.4, 2.5 µmol•L⁻¹, respectively.