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Published on: December 4, 2013
Pleiocarpumlignan A, a new dineolignan from Piper pleiocarpum Chang ex Tseng
Wen-Hui Xu1, Xiao-Min Su1, Xin-Min Zhang2
1Key Laboratory for Forest Resources Conservation and Utilization in the Southwest Mountains of China, Ministry of Education, Southwest Forestry University , Kunming , PR China.
Abstract:
The investigation of chemical constituents from the whole plants Piper pleiocarpum Chang ex Tseng resulted in the isolation of one new dineolignan, pleiocarpumlignan A (1), along with one known benzoate derivative, trans-2,3-diacetoxy-1-[(benzoy1oxy)methyl]-cyclohexa-4,6-diene (2), and two known neolignans (3-4) as (±)-trans-dehydrodiisoeugenol (3), (7R,8R,3'S)-△8'-3',6'-dihydro-3'-methoxy-3,4-methylenedioxy-6'-oxo-8,3',7,O,4'-lignan (4). Their structures were elucidated through extensive spectroscopic analyses including 1D, 2D NMR, HR-ESI-MS, and by comparison with the literature. All compounds (1-4) were firstly isolated from Piper pleiocarpum Chang ex Tseng. The 13C NMR spectra of 2 were completely assigned for the first time. Cytotoxic activities of these isolated compounds against five human cancer cell lines (including A-549, SMMC-7721, HL-60, MCF-7, and SW-480) were evaluated.
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