Rukamtenol, a new spiro compound isolated from Flacourtia rukam Zoll. & Moritzi growing in Vietnam

• Published in: Natural product research 2022-04, Vol.36 (8), p.1966-1972
• Main Authors: Thai, Cam Thi, Duong, Thuc-Huy, Trung, Nguyen Tien, Phan, Cam-Tu D., Nguyen, Quoc Vuong, Nguyen, Tuyen Le-Thanh, Watanabe, Kazuki, Do, Tuoi Thi-Hong, Huynh, Thuy Ngoc, Tran, Hung
• Format: Article
• Language: English
• Subjects: Antineoplastic Agents - chemistry; DP4 probability; Flacourtia; Flacourtia rukam; flacourtin; Molecular Structure; Rukamtenol; spiro; Spiro Compounds; Vietnam
• ISSN: 1478-6419; 1478-6427
• DOI: 10.1080/14786419.2020.1839451

Chemical investigation of chloroform extract of Flacourtia rukam Zoll. & Moritzi stems led to the isolation of one new compound namely rukamtenol together with four known compounds, viz., chaulmooric acid, flacourtin, 3,4,5-trimethoxyphenyl β-D-glucopyranoside, and daucosterol. Their structures and relative stereochemistry have been determined by 1D and 2D NMR analysis, high resolution mass spectroscopy, and compared with those in literatures. Rukamtenol represented the first 2-oxaspiro[4.4]non-8-en-3-one in nature. The relative configuration of rukamtinol was defined using DFT-NMR chemical shift calculations and subsequent DP4 probability method. Rukamtenol, flacourtin, and 3,4,5-trimethoxyphenyl β-D-glucopyranoside were tested for cytotoxic activity toward three MDA-MB-231, HepG2, and RD cancer cell lines. However, they failed to reveal any activity (IC 50  > 100 μM) on these cell lines.