A sesquiterpenoid tropolone and 1,2,3,4-tetrahydronaphthalene derivatives from Olax imbricata roots

• Published in: Fitoterapia Vol. 132; pp. 1 - 6
• Main Authors: Nguyen, Huong T.M., Vo, Nga T., Huynh, Suong T.M., Do, Lien T.M., Aree, Thammarat, Tip-pyang, Santi, Phan, Cam-Tu D., Trung, Nguyen T., Nguyen, Phung K.P.
• Format: Journal Article
• Language: English
• Published: Netherlands Elsevier B.V 01.01.2019; Elsevier Science Ltd
• Subjects: Biotechnology; Cancer; Circular dichroism; Configurations; Cytotoxicity; Derivatives; Dichroism; Experiments; NMR; Nuclear magnetic resonance; Olax imbricata; Olaximbrisides A–D; Roots; Sesquiterpenoid; Tetrahydronaphthalene; Tropolone; Tumor cell lines; X-ray diffraction; Olax imbricata; Tropolone; Cytotoxicity; Olaximbrisides A–D; Sesquiterpenoid; Tetrahydronaphthalene
• ISSN: 0367-326X; 1873-6971
• DOI: 10.1016/j.fitote.2018.11.007

The methanol extract of Olax imbricata roots afforded one new sesquiterpenoid tropolone and three new 1,2,3,4-tetrahydronaphthalene derivatives, olaximbrisides A–D (1–4). Their structures were determined by 1D and 2D NMR experiments in combination of HRESIMS. The relative configurations were assigned by the NOESY experiments. The absolute configurations were established by a combination of X-ray diffraction analysis and electronic circular dichroism (ECD) experiments. All isolated compounds were evaluated for their cytotoxic effects against some cancer cell lines. Among them, compound 1 exhibited the cytotoxicities against MCF-7, HepG2 and LU cell lines with IC50 values of 16.3, 34.3 and 8.0 μM, respectively. [Display omitted] •One sesquiterpenoid tropolone (1) was isolated from Olax imbricata roots.•Three 1,2,3,4-tetrahydronaphthalene derivatives (2–4) were isolated from Olax imbricata roots.•Olaximbriside A (1) exhibited cytotoxicity against three cancer cell lines (MCF-7, HepG2 and LU).