A New Taraxastane Triterpene from Euphorbia Denticulata with Cytotoxic Activity Against Prostate Cancer Cells.

In this research, aerial parts of Euphorbia denticulata Lam were collected from Sanandaj city in Kurdistan province at the West of Iran. It was extracted by maceration using acetone as solvent. The isolation of compounds were carried out with repeated column chromatography using silica gel and normal preparative HPLC using YMC-Pack-Sil column and hexane: ethyl acetate as mobile phase. The structures of isolated compounds were elucidated by extensive 1 and 2D-NMR as well as HRESI-MS spectra and the cytotoxicity was done against DU-145 human prostate cancer cell line using standard MTT assay. It afforded a new 12-taraxastane derivative and two known cycloartane triterpenes including: taraxast-12-ene-3ß,20,21(α)-triol (1), cycloartane-3ß,25-diol (2), and cycloartane-3ß,24,25-triol (3). They exhibited cytotoxic effects, with IC50 values of 12.2 ± 2.9, 27.5 ± 4.9, and 18.3 ± 1.4 µM, respectively.

New macrocyclic diterpenes from Euphorbia connata Boiss. with cytotoxic activities on human breast cancer cell lines.

Acetone:chloroform (1:2) extract of the aerial parts of Euphorbia connata Boiss. (Euphorbiaceae) was investigated for its diterpenoids. This led to the isolation of one known and two new diterpenes, belonging to the pentahydroxy-13(17)-epoxy-8,10(18)-myrsinadiene and tetrahydroxy-5,6-epoxy-14-oxo-jatropha-11(E)-ene classes. The structures were elucidated based on (13)C and (1)H NMR as well as 2D NMR, IR and MS spectra and the cytotoxicity for compounds 1-3 were evaluated by using MTT assay against two human breast cancer cell lines. Myrsinane-type compounds - 3,7,14,15-tetraacetyl-5-propanoyl-13(17)-epoxy-8,10(18)-myrsinadiene (1) and 3,7,10,14,15-pentaacetyl-5-butanoyl-13,17-epoxy-8-myrsinene (2) - exhibited moderate inhibitory effects, with IC50 values of 24.53 ± 3.39 and 26.67 ± 1.41 µM against the MDA-MB cell line, and 37.73 ± 3.41 and 34.57 ± 2.12 µM against the MCF-7 cell line, respectively. Jatrophane-type diterpene - 5,6-epoxy-8,9,15-triacetyl-3-benzoyl-14-oxo-jatropha-11(E)-ene (3) - showed weak cytotoxicity, with IC50 values of 55.67 ± 7.09 µM against MDA-MB, and moderate cytotoxicity with IC50 values of 24.33 ± 3.21 µM against MCF-7 cell line.

Triterpenes and Steroids from Euphorbia denticulata Lam. With Anti-Herpes Symplex Virus Activity.

In this research, dried acetone:chloroform extract of aerial parts of E. denticulata as one of the endemic plants to Iran, afforded a number of triterpenes and steroids including: betulin, 24-methylene-cycloart-3-ol, cycloart-23Z-ene-3ß,25-diol, cycloart-23E-ene-3ß,25- diol, ergosta-8,24-dien-3-ol (obtusifoliol) and beta-sitosterol which were reported for the first time from this plant. The structure of these compounds was elucidated by NMR and mass spectroscopic methods. The MTS assay was used to determine the toxicity and antiviral activity of betulin and (3ß,23E)-cycloarta-23-ene-3,25-diol. Betulin showed anti-HSV-1 activity with EC50 value of 84.37±0.02 µg/mL, and toxicity on normal vero cells with CC50 value of 660.718±0.072 µg/mL. (3ß,23E)-Cycloarta-23-ene-3,25-diol showed antiviral effect with EC50 value of 86.63±0.03 µg/mL, and toxicity with CC50 value of 1089.21±0.25 µg/mL. The results revealed that these two compounds have the antiviral activity far below the CC50 value with selectivity index (CC50/EC50) values of 7.83, and 12.57, respectively.