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Updated: Jan 21, 2026

An In Vitro Assay to Detect tRNA-Isopentenyl Transferase Activity
Published on: October 8, 2018
Two new 8-isopentenyl isoflavane derivatives from Astragalus dolichochaete diels
Ding-Wei Wang1, Chao-Jiang Xiao1, Lin Qiu1
1Institute of Materia Medica, Dali University, Dali, P. R. China.
Abstract:
Astragali Radix (Huangqi) is one of the well-known traditional Chinese medicines and has been used in China for more than two thousand years. As a close species, Astragalus dolichochaete Diels was found to possess cytotoxicity during our preliminary study of Astragalus plants from Yunnan Province, China. To better understand the chemical foundation of the cytotoxicity, the major constituents of A. dolichochaete were studied. As a result, two new 8-isopentenyl isoflavane derivatives, dolichochaeteins A and B (1 and 2), together with ten known constituents were isolated, and their structures were elucidated by means of spectroscopy, mainly 1D and 2D NMR techniques. The cytotoxic activities were evaluated for the raw extract, ethyl acetate fraction, compound 2 and glyasperin H (3) against human gastric carcinoma cell line SGC-7901, human hepatoma cell line SMMC-7721 and human leukemic cell line K562. All the samples exhibited significant cytotoxicity.
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