Triterpene compounds—VII

Chopra, C. S.; Cole, A.R.H.; Theiberg, K.J.L.; White, DE; Arthur, HR

doi:10.1016/s0040-4020(01)98316-4

Cited by 15 publications

(5 citation statements)

References 21 publications

Supporting

Mentioning

Contrasting

Unclassified

Order By: Relevance

“…Loss of CH 2 OH from m/z 222 results in the formation of m/z 191 further confirming the C-27 position of CH 2 OH group. The chemical shifts in 13 C-NMR (DEPT I, II, III) spectra suggested a close resemblance with 20-(29) lupane derivatives [12]. The quarternary carbon linked to vinylic carbon resonated at 150.4.…”

Section: Resultsmentioning

confidence: 92%

Triterpenoids from the stembark ofPyrus Communis

Mehta

Verma²,

Jafri³

et al. 2003

Natural Product Research

View full text Add to dashboard Cite

show abstract

Section: Resultsmentioning

confidence: 92%

Triterpenoids from the stembark ofPyrus Communis

Mehta

Verma²,

Jafri³

et al. 2003

Natural Product Research

View full text Add to dashboard Cite

show abstract

“…The NMR data of compound 7 were very similar to those of cylicodiscic acid methyl ester (8), 23 with the only difference being the replacement of the hydroxymethyl group at the C-27 position of 8 (δ C-27 60.1) with a carboxylic acid group in 7 (δ C-27 178.4). The dicarboxylic acid analogue at C-27 and C-28 is known as melaleucic acid (9), isolated from Melaleuca species, 24 while compound 7 corresponds to the mono methyl ester at C-28 of 9, which was verified by the HMBC correlations of 7 observed from H-18 (δ H 1.62) and OCH 3 (δ H 3.67) to C-28 (δ C 176.7). Accordingly, compound 7 was proposed as melaleucic acid 28-O-methyl ester.…”

Section: ■ Results and Discussionmentioning

confidence: 99%

Identification of BMI1 Promoter Inhibitors from Beaumontia murtonii and Eugenia operculata

et al. 2017

View full text Add to dashboard Cite

B-Cell-specific Moloney murine leukemia virus insertion region 1 (BMI1) is a core component of the polycomb repressive complex 1 (PRC1). Abnormal expression of BMI1 is associated with a number of human malignances and cancer stem cells (CSCs), which cause chemotherapy resistance. Therefore, small molecules that inhibit BMI1 expression are potential candidates for cancer therapy. In this study, a cell-based reporter gene assay was developed that allowed BMI1 promoter activity to be measured in 293T human embryonic kidney cells based on luciferase expression levels. Using this screening assay, the methanol-soluble extracts of Beaumontia murtonii and Eugenia operculata were selected as leads. Bioassay-guided fractionation of the extracts led to the isolation of three known cardenolides (1-3) and one new compound (4) from B. murtonii and two known triterpenoids (5 and 6) and one new compound (7) from E. operculata. These seven compounds inhibited BMI1 promoter activity (IC range 0.093-23.0 μM), and the most active compound, wallichoside (1), was further evaluated. Western blot analysis revealed that wallichoside (1) decreases BMI1 protein levels in HCT116 human colon carcinoma cells, and flow cytometry analysis showed that it significantly reduced levels of the CSC biomarker epithelial cell adhesion molecule. Wallichoside (1) also inhibited sphere formation of Huh7 human hepatocellular carcinoma cells, indicating that it diminished the self-renewal capability of CSCs.

show abstract

“…Some of these values are experimental, but others were not found in literature, because of which we used values calculated with parameterized softwares. 4,[75][76][77] Since MelAc has a structure with two opposite carboxyls, making it harder to pack in a more compact solid state, it would be expected to have a lower melting point than BetAc. However, its melting point is almost 65 o C higher, suggesting very high order in the solid phase, and greater interaction and stability.…”

Section: Clusters and Activitymentioning

confidence: 99%

“…Many studies with organic molecules use this association to explain biochemical activities, so that comparable activities of analogous compounds are easily explained. [1][2][3][4][5][6] However, when analogous compounds exhibit distinct activities, the low-activity compound generally loses importance. Mostly, the reason for the difference in activities is ignored.…”

Section: Introductionmentioning

confidence: 99%

Geometry and Stability of Molecular Clusters: Factor to Be Considered in Biomolecular Activity

Silva¹,

Alecrim²,

Costa³

et al. 2018

J. Braz. Chem. Soc.

View full text Add to dashboard Cite

Betulinic and melaleucic acids, lupan-skeleton triterpenes with very similar structure, present marked differences in anti-malarial activity. While betulinic acid and some of its analogs exhibit strong activity, melaleucic acid is inactive. In the present work, a theoretical approach was used to explain such differences, using Austin Model 1 (AM1) and density functional theory (DFT)/ Becke, three-parameter, Lee-Yang-Parr (B3LYP) approaches, and AutoDock Vina calculations. The initial results showed no significant differences between structural and electronic properties. On the other hand, studies of the geometry of molecular clusters with both compounds revealed significant differences. Melaleucic acid clusters were shown to be stable enough to influence the substrate-protein interaction, unlike betulinic acid, which was unable to form clusters comparable to melaleucic acid ones. The present study suggests the molecular clusters as a new factor that has a great influence on the mechanism of biomolecular activity.

show abstract

Triterpene compounds—VII

Cited by 15 publications

References 21 publications

Triterpenoids from the stembark ofPyrus Communis

Triterpenoids from the stembark ofPyrus Communis

Identification of BMI1 Promoter Inhibitors from Beaumontia murtonii and Eugenia operculata

Geometry and Stability of Molecular Clusters: Factor to Be Considered in Biomolecular Activity

Contact Info

Product

Resources

About