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A Customizable Approach for the Enzymatic Production and Purification of Diterpenoid Natural Products
Published on: October 4, 2019
Eremophilane sesquiterpene lactones from Ligularia virgaurea ssp. oligocephala
Quan-Xiang Wu1, Yan-Ping Shi, Li Yang
1National Laboratory of Applied Organic Chemistry, Lanzhou University, Lanzhou, PR China.
Abstract:
From an extract of the whole plant of Ligularia virgaurea ssp. oligocephala, three new eremophilane sesquiterpene lactones, 10alpha-hydroxy-1-oxoeremophila-7(11),8(9)-dien-12,8-olide (1), 6alpha,10alpha-dihydroxy-1-oxoeremophila-7(11),8(9)-dien-12,8-olide (2), 6beta,10beta-dihydroxyeremophila-7(11),8(9)-dien-12,8-olide (3), as well as four known sesquiterpene lactones with the same carbon skeleton, named toluccanolides A-C (4, 5, 7) and 6beta-hydroxy-8alpha-methoxyeremophila-1(10),7(11)-dien-12,8beta-olide (6) were isolated. Their structures were elucidated by spectroscopic methods including intensive 2D NMR techniques (gCOSY, gHMQC, gHMBC and 1H-1H NOESY for 2) and HR-ESI-MS.
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