Acetylursolic acid

Cytotoxic triterpenes from the aerial roots of Ficus microcarpa.[Pubmed: 15694457 ]

Phytochemistry. 2005 Feb;66(4):495-501.

METHODS AND RESULTS:
Six triterpenes, 3beta-acetoxy-12,19-dioxo-13(18)-oleanene (1), 3beta-acetoxy-19(29)-taraxasten-20alpha-ol (2), 3beta-acetoxy-21alpha,22alpha-epoxytaraxastan-20alpha-ol (3), 3,22-dioxo-20-taraxastene (4), 3beta-acetoxy-11alpha,12alpha-epoxy-16-oxo-14-taraxerene (5), 3beta-acetoxy-25-methoxylanosta-8,23-diene (6) along with nine known triterpenes, 3beta-acetoxy-11alpha,12alpha-epoxy-14-taraxerene (7), 3beta-acetoxy-25-hydroxylanosta-8,23-diene (8), oleanonic acid (9), acetylbetulinic acid (10), betulonic acid (11), Acetylursolic acid (12), ursonic acid (13), ursolic acid (14), and 3-oxofriedelan-28-oic acid (15) were isolated from the aerial roots of Ficus microcarpa, and their structures elucidated by spectroscopic methods. The in vitro cytotoxic efficacy of these triterpenes was investigated using three human cancer cell lines, namely, HONE-1 nasopharyngeal carcinoma, KB oral epidermoid carcinoma, and HT29 colorectal carcinoma cells.
CONCLUSIONS:
Compound 8 and pentacyclic triterpenes 9-15 possessing a carboxylic acid functionality at C-28 showed significant cytotoxic activities against the aforementioned cell lines and gave IC50 values in the range 4.0-9.4 microM.

Suppression of the SOS-inducing activity of mutagenic heterocyclic amine, Trp-P-1, by triterpenoid from Uncaria sinensis in the Salmonella typhimurium TA1535/pSK1002 Umu test.[Pubmed: 15769173 ]

J Agric Food Chem. 2005 Mar 23;53(6):2312-5.

METHODS AND RESULTS:
The methanol extract from Uncaria sinensis showed a suppressive effect on umu gene expression of the SOS response in Salmonella typhimurium TA1535/pSK1002 against the mutagen 3-amino-1,4-dimethyl-5H-pyrido[4,3b]indole (Trp-P-1), which requires liver metabolizing enzymes. The methanol extract from U. sinensis was re-extracted with hexane, CH2Cl2, BuOH, and water, respectively. CH2Cl2 extract showed a suppressive effect. A suppressive compound 1 in CH2Cl2 extract was isolated by SiO2 column chromatography. Compound 1 was identified as ursolic acid by IR, electron ionization EI-MS, and NMR spectroscopy. Suppressive effects of ursolic acid (1) and its derivatives, methyl ursolate (1M), Acetylursolic acid (1A), and methyl acetylursolate (1MA), were determined in the umu test.
CONCLUSIONS:
These compounds suppressed 61.3, 37.7, 71.5, and 37.8% of the Trp-P-1-induced SOS response at a concentration of 0.4 micromol/mL, respectively. The ID50 values of compounds 1 and 1A were 0.17 and 0.20 micromol/mL. In addition, these compounds were assayed with the activated Trp-P-1. Suppressive effects on activated Trp-P-1 were decreased as compared with those of Trp-P-1.

Anti-plasmodial activity of some Zulu medicinal plants and of some triterpenes isolated from them.[Pubmed: 24108397 ]

Molecules. 2013 Oct 8;18(10):12313-23.

Mimusops caffra E. Mey. ex A.DC and Mimusops obtusifolia Lam (both members of the Sapotaceae family), and Hypoxis colchicifolia Bak (family Hypoxidaceae) are used by traditional healers in Zululand to manage malaria.
METHODS AND RESULTS:
Anti-plasmodial investigation of the crude extracts and some triterpenes isolated from the plants showed activity against a chloroquine sensitive (CQS) strain of Plasmodium falciparum (D10). Among the crude extracts the leaves of M. caffra exhibited the highest activity, with an IC₅₀ of 2.14 μg/mL. The pentacyclic tritepenoid ursolic acid (1), isolated from the leaves of M. caffra was the most active compound (IC₅₀ 6.8 μg/mL) as compared to taraxerol (2) and sawamilletin (3) isolated from the stem bark of M. obtusifolia (IC₅₀ > 100). Chemical modification of the ursolic acid (1) to 3β-Acetylursolic acid (4) greatly enhanced its anti-plasmodial activity. Compound 4 reduced parasitaemia against Plasmodium berghei by 94.01% in in vivo studies in mice.
CONCLUSIONS:
The cytotoxicity of 3β-Acetylursolic acid (IC₅₀) to two human cell lines (HEK293 and HepG2) was 366.00 μg/mL and 566.09 μg/mL, respectively. The results validate the use of these plants in folk medicine.

Tetrahedron.1994 Feb21; 50(8):2591–2598.

Oxidative decarboxylation by hydrogen peroxide and a mercury (II) salt: A simple route to nor-derivatives of acetyloleanolic, acetylursolic and dehydroabietic acids.[Reference: WebLink]

Treatment of carboxylic acids with hydrogen peroxide in the presence of a mercury (II) salts results in oxidative decarboxylation and is an effective method for transformation of the carboxylic acids into the corresponding nor-derivatives, hydroperoxides and alcohols. Oxidative decarboxylation of acetyloleanolic acid, Acetylursolic acid and dehydroabietic acid is described.