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Polyacetylenes from the roots of Cirsium japonicum var. ussuriense
Seung Hyun Lee1, Jun Gu Kim1, Thi Phuong Linh Le1
1College of Pharmacy, Chungbuk National University, Cheongju, 28610, Republic of Korea.
Abstract:
Eight previously undescribed polyacetylenes, cirussurynes A-H, were isolated from the methanolic extract of the roots of Cirsium japonicum var. ussuriense. Their structures were elucidated by interpretation of extensive 1D and 2D NMR spectroscopy and HRESIMS spectrometry data. The configuration of triols in cirussurynes A, B, and E-G was deduced by the J-value based configuration analysis together with specific rotation values. All compounds were evaluated for their inhibitory effects on nitric oxide production against LPS-induced RAW 264.7 macrophages, and exhibited IC50 values ranging from 5.5 to 68.7 μM.
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