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Taxodikaloids A and B, Two Dimeric Abietane-Type Diterpenoids from Taxodium ascendens Possessing an Oxazoline Ring
Xing-Hao Huang1, Ling-Xue Tao, Chang-Qiang Ke
1University of Chinese Academy of Sciences , No. 19A Yuquan Road, Beijing 100049, China.
Abstract:
Two dimeric diterpenoids, taxodikaloids A (1) and B (2), have been identified from the seeds of Taxodium ascendens. The diterpenoid structures were established on the basis of comprehensive spectroscopic analysis, and the absolute configuration of taxodikaloid A (1) was further confirmed by single-crystal X-ray diffraction. Both structures feature an unprecedented oxazoline ring linkage connecting two abietane diterpenoid monomers. A plausible biosynthetic pathway for compounds 1 and 2 is proposed. Both compounds show potential neuroprotective activity against Aβ25-35-induced damage in SH-SY5Y cells.
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