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Yuan-chao Li

Publications and source records attributed to Yuan-chao Li.

4 recordsLinked to original sources
PubMed2005

[Isolation and structure identification of chemical constituents from Anabasis brevifolia].

AIM: To study the chemical consitituents of the n-butanol-extracts of Anabasis salsa and Various chromatographic techniques were used to the chloroform-extract of Anabasis brevifolia. METHODS: separate and purify the constituents. Their physico-chemical properties and spectral data were used to elucidate their structures. RESULTS: Five compounds were isolated and identified as 2-O-beta-D-glucopyranosyloxy-4,6-dimethoxy phenylenthanone (1), 2-O-(2)-beta-D-glucopyranosyloxy-4, 6-dimethoxy phenylenthanone (2), 3-methyl-but-2-enoic acid-[2-(4-methoxy phenyl)-ethyl]-amide (3), 5,6,7,2'-tetramethoxy isoflavonoid (4), 2'-hydroxy-5,6,7-trimethoxyisoflavonoid (5). CONCLUSION: Compounds 2, 3, and 5 are new compounds. And the others were isolated from Anabasis L. for the first time.

Chenopodiaceae↗
PubMed2002

[Studies on the chemical constituents of Lycianthes biflora].

AIM: To study the chemical constituents of Lycianthes biflora. METHODS: Column chromatography was used to separate the chemical constituents. IR, MS, 1HNMR, 13CNMR and 2D-NMR technique were used to determine the structures of the isolated constituents. RESULTS: Five compounds were isolated from this plant. Their structures were identified to be bifloride A (1), N-trans-cinnamoyltyramine (2), liquiritigenin (3), N-trans-p-coumaroyloctopamine (4), 1-O-beta-D-glucopyranosyl-2-N-2'-hydroxypalmitoyl-sphinga-4- trans-8-trans-dienine (5). CONCLUSION: Compounds 1 and 2 are new compounds, the others were isolated from this plant for the first time. Compound 2 showed inhibitory effects on P-388.

4-Butyrolactone↗
PubMed2002

[Isolation and structure of wilfordlonging from Tripterygium wilfordii Hook. f].

AIM: To study the chemical composition of Tripterygirm wilfordii Hook. f. METHODS: Colunm chromatography was used to separate the chemical constituents. UV, IR, MS, HRMS, 1HNMR, 13CNMR (COM and OFR), 1H-1H COSY, 1H-13C COSY, NOESY and COLOC spectra were used to determine the structures of the isolated constituents. RESULTS: Two sesquiterpene alkaloids were isolated and their structures were elucidated as wilforgine and wilfordlongine on the basis of spectral evidence. CONCLUSION: Wilfordclonine is a new sesquiterpene alkaloid.

Lactones↗