【摘 要】
:
Two novel ent-kauranoids with new sub-skeleton types, gesneroidins G and H were isolated as white powder from the ether extract of the leaves of Isodon gesneroi
【出 处】
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Chinese Chemical Letters
论文部分内容阅读
Two novel ent-kauranoids with new sub-skeleton types, gesneroidins G and H were isolated as white powder from the ether extract of the leaves of Isodon gesneroides through normal phase column chromatography. Their structures were elucidated as 3b,6a,7b-triacetoxyl-15-hydroxyl-14-oxo-ent-15,16-seco-kaur-11,17-olide and 1a-hydroxyl-3b,6a,7b,11b-tetraacetoxyl-ent-nor-15,17-kaur-8,16-olide on the basis of the spectral evidences including 1D and 2D NMR spectra.
Two novel ent-kauranoids with new sub-skeleton types, gesneroidins G and H were isolated as white powder from the ether extract of the leaves of Isodon gesneroides through normal phase column chromatography. Their structures were elucidated as 3b, 6a, 7b-triacetoxyl- 15-hydroxyl-14-oxo-ent-15,16-seco-kaur-11,17- olide and 1a-hydroxyl-3b, 6a, 7b, 11b- tetraacetoxyl-ent-nor-15,17-kaur- 16-olide on the basis of the spectral evidences including 1D and 2D NMR spectra.
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