New Cytotoxic Lupane Lactones from Kokoona ochracea

Abstract

Three new compounds, ochraceolides A, B, and C, were isolated from nonpolar extracts derived from Kokoona ochracea stem bark. Based on spectroscopic data, their structures were determined to be the closely related lupane lactones: 3-oxolup-20(29)-en-30,21 alpha-olide, 20,29-epoxy-3-oxolupan-30,21 alpha-olide, and 3,6-dioxolup-20(29)-en-30,21 alpha-olide. Compounds 1 and 3 exhibited significant cytotoxic activity with cultured P-388 cells (ED50 values of 0.26 and 0.53 microgram/ml, respectively) but were at least tenfold less active with a variety of human tumor cell lines. Compound 2 was weakly active with cultured P-388 and KB-3 cells (ED50 values of 7.8 and 5.2 micrograms/ml, respectively), but no significant activity was observed with other human cancer cell types (ED50 values of more than 20 micrograms/ml).

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“…The presence of the sugar carbons C-2' and C-4' in the deshielded region supported furanic form of the sugar unit. The carbon signals of the triterpenic unit were compared with related lupene-type molecules [20][21][22] . Alkaline hydrolysis of this compound yielded Lup-12, 20 (29)-dien-3β-ol, α-L arabinose and oleic acid.…”

“…The following bacterial and fungal strains were used in the study, Staphylococcus epidermidis MTCC-3615, Bacillus cereus MTCC-430, Pseudomonas aeruginosa MTCC-424, Escherichia coli MTCC-443, Aspergillus niger MTCC-1344 and Candida albicans MTCC-227. The antibacterial activity of all compound were studied by agar well diffusion method 22 with slight modification. Molten nutrient agar (25 ml) was poured into presterilized petriplates and allowed to solidify at room temperature.…”

Crystal structure of ochraceolide A isolated fromElaeodendron trichotomum(Turcz.) Lundell

“…Ochraceolide A was firstly isolated from Kokoona ochracea (Elm.) Merril stem bark (Ngassapa et al, 1991) and afterwards from Lophopetalum wallichii (Sturm et al, 1996) and Cassine xylocarpa (Callies et al, 2015). The title compound has shown significant cytotoxic activity against murine lymphocytic leukemia cells (P-388) with an ED 50 of 0.6 mM; human oral epidermoid carcinoma (KB-3) with an ED 50 of 6.0 mM; and hormonedependent breast cancer with an ED 50 of 9.9 mM (Ngassapa et al, 1991;Sturm et al, 1996).…”

“…Merril stem bark (Ngassapa et al, 1991) and afterwards from Lophopetalum wallichii (Sturm et al, 1996) and Cassine xylocarpa (Callies et al, 2015). The title compound has shown significant cytotoxic activity against murine lymphocytic leukemia cells (P-388) with an ED 50 of 0.6 mM; human oral epidermoid carcinoma (KB-3) with an ED 50 of 6.0 mM; and hormonedependent breast cancer with an ED 50 of 9.9 mM (Ngassapa et al, 1991;Sturm et al, 1996). In the same way, this compound has exhibited significant inhibitory activity in the FPTase assay with an IC 50 of 2.2 mM (Sturm et al, 1996) and inhibitory effects of human immunodeficiency virus type 1 replication with an IC 50 of 39.0 mM (Callies et al, 2015).…”

The Potential of Triterpenoids in the Treatment of Melanoma

“…The last type of natural pentacyclic triterpenes active against melanoma are ochraceolides, compounds with modified E-ring. Ochraceolides A (6) and C (7) were isolated together with other lupane derivatives from Kokoona ochracea and their activity against line UISO-MEL-2 was approximately 15 mol/L (Ngassapa et al, 1991).…”