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Updated: Jan 13, 2026

Preparation of a Corannulene-functionalized Hexahelicene by CopperI-catalyzed Alkyne-azide Cycloaddition of Nonplanar Polyaromatic Units
Published on: September 18, 2016
A new cyclohexenone and two new phenanthrones from Elatostema tenuicaudatum
Dao Duc Thien1, Nguyen Hoang Sa2, Le Quoc Thang3
1Institute of Chemistry, Vietnam Academy of Science and Technology, 18 Hoang Quoc Viet, Nghia Do, Cau Giay, Ha Noi, Vietnam.
Abstract:
A new cyclohexenone, 5S-(3,4-dihydroxyphenethyl)cyclohex-2-en-1-one (1), along with two new phenanthrones, (4aS,10aS)- 1,9,10,10a -tetrahydro-4a,6,7-trihydroxy-4(4aH)-phenanthrone (2) and (4aS,10aS)-4a-hydroxy-7-methoxy-1,9,10,10a-tetrahydro-4(4aH)-phenanthrone 6-O-β-D-glucopyranoside (3) were isolated from the whole plant of Elatostema tenuicaudatum. The structures were determined by spectroscopic methods including 1D, 2D NMR and HR-ESI-MS. The absolute configurations of compounds 1-3 were determined by their experimental and calculated ECD spectral data. The isolates were evaluated for inhibitory activity on nitric oxide (NO) production in lipopolysaccharide (LPS)-activated RAW 264.7 macrophage cells, and compound 2 showed the strongest activity with an IC50 value of 9.5 ± 1.2 μM.
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