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A Customizable Approach for the Enzymatic Production and Purification of Diterpenoid Natural Products
Published on: October 4, 2019
Three new sesquiterpene lactone dimers from Carpesium macrocephalum
Jian-Ping Zhang1, Xi-Ke Xu1, Ji Ye1
1School of Pharmacy, Second Military Medical University, Shanghai 200433, PR China.
Abstract:
Three new sesquiterpene lactone dimers (SLDs), carpedilactones E-G (1-3), together with two known monomeric units, ivalin (4) and alantolactone (5), were isolated from the acetonic extract of Carpesium macrocephalum. Their chemical structures were elucidated by IR, UV, HR-ESI-MS, NMR 1D and 2D experiments, and the absolute configuration of 1-3 was resolved according to the (1)H NMR and CD spectrographic features of 1,3-/2,4-linked SLDs. Furthermore, 1 was unambiguously confirmed by Cu-Kα X-ray crystallographic analysis. Additionally, compounds 1 and 2 were revealed with potent cytotoxicities against human colon cancer HCT116 cells with IC50 values of 2.27 and 3.30 μM, respectively.
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