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PubMed · 9611828

Limonoids from Azadirachta excelsa.

B Cui·H Chai·H L Constant·T Santisuk·V Reutrakul·C W Beecher·N R Farnsworth·G A Cordell·J M Pezzuto·A D Kinghorn
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Abstract

Activity-directed fractionation of a stem extract of Azadirachta excelsa using KB (human oral epidermoid carcinoma) cells led to the isolation of four meliacin-type limonoids. Two of these constituents were novel, namely, 2,3-dihydronimbolide and 3-deoxymethylnimbidate, and these were purified along with the known compounds, nimbolide and 28-deoxonimbolide. The structures of the new compounds were determined by spectroscopic methods. Nimbolide and 28-deoxonimbolide were broadly cytotoxic when evaluated against a panel of human cancer cell lines, while the two novel compounds were inactive in this regard. The defection of nimbolide and 28-deoxonimbolide as cytotoxic constituents was facilitated by an electrospray LC/MS dereplication procedure.

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Antineoplastic Agents, PhytogenicCholenesDiterpenesDrug Screening Assays, AntitumorHumansLactonesLimoninsPlants, MedicinalSecosteroidsSpectrum AnalysisTumor Cells, CulturedJournal ArticleResearch Support, U.S. Gov't, P.H.S.

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B Cui, H Chai, H L Constant, T Santisuk, V Reutrakul, C W Beecher, N R Farnsworth, G A Cordell, J M Pezzuto, A D Kinghorn. 1998. Limonoids from Azadirachta excelsa.. https://doi.org/10.1016/s0031-9422(97)00711-5

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