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Grindelane diterpenoids from Stevia subpubescens.

L U Román·J I Cambrón·R E del Río·J D Hernández·C M Cerda-García-Rojas·P Joseph-Nathan
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Abstract

Four new 9R,13R-epoxylabdane diterpenes (1-4) and a known clerodane derivative, 3,4beta-epoxy-5beta,10beta-cis-17alpha, 20alpha-clerod-13(14)-en-15,16-olide, were isolated from the leaves of Stevia subpubescens. The structures, which correspond to the grindelane class of diterpenoids, were elucidated by NMR data, chemical correlation, and single-crystal X-ray diffraction analysis of monoacetate 5. The absolute configuration of 1-4 is based on the optical activity of ketone 3 as compared with data of closely related substances.

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AcetylationAsteraceaeCrystallography, X-RayDiterpenesHydrolysisMagnetic Resonance SpectroscopyMolecular ConformationOxidation-ReductionPlant ExtractsPlant LeavesSpectrophotometry, InfraredJournal ArticleResearch Support, Non-U.S. Gov't

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L U Román, J I Cambrón, R E del Río, J D Hernández, C M Cerda-García-Rojas, P Joseph-Nathan. 2000. Grindelane diterpenoids from Stevia subpubescens.. https://doi.org/10.1021/np990216i

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