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Updated: Jun 3, 2026

Quantitative 31P NMR Analysis of Lignins and Tannins
Published on: August 2, 2021
Lignans and neolignans from Sinocalamus affinis and their absolute configurations
Liang Xiong1, Chenggeng Zhu, Yanru Li
1Institute of Materia Medica, Chinese Academy of Medical Sciences and Peking Union Medical College, Key Laboratory of Bioactive Substances and Resources Utilization of Chinese Herbal Medicine, Ministry of Education, Beijing 100050, People's Republic of China.
Abstract:
Twenty-two new lignans and neolignans (1-22), together with 14 known analogues, have been isolated from an ethanolic extract of the stem (with skin removed) of Sinocalamus affinis. Their structures were elucidated by spectroscopic and chemical methods. On the basis of systematic NMR and circular dichroism (CD) data analysis, the validity of J7,8 and ΔδC8-C7 values to distinguish threo and erythro aryl glycerol units in different neolignans and the CD data [particularly the Rh2(OCOCF3)4-induced CD data (the E band)] to determine the absolute configurations at C-8 (C-7) of the aryl glycerol units are discussed. At a concentration of 10 μM, compounds 20 and 22 inhibited NO production in mouse peritoneal macrophages 84.2±5.9% and 71.7±1.0%, respectively. Compounds 19, 20, and 22 showed activity against serum deprivation induced PC12 cell damage by increasing the cell viability from 80.7±2.8% to 91.6±6.4%, 107.2±8.0%, and 97.6±8.5%, respectively.
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