Laevifins A–G, clerodane diterpenoids from the Bark of Croton oblongus Burm.f.

• Published in: Phytochemistry
• Main Author: Aziz A.N.; Ismail N.H.; Halim S.N.A.; Looi C.Y.; Anouar E.H.; Langat M.K.; Mulholland D.; Awang K.
• Format: Article
• Language: English
• Published: Elsevier Ltd 2018
• Online Access: https://www.scopus.com/inward/record.uri?eid=2-s2.0-85054462501&doi=10.1016%2fj.phytochem.2018.10.002&partnerID=40&md5=20bf302bd9307da96ad2364148f525ec
• ISSN: 319422
• DOI: 10.1016/j.phytochem.2018.10.002

A phytochemical investigation of the stem barks of the Malaysian Croton oblongus Burm.f. (Syn. Croton laevifolius Blume) (Euphorbiaceae) yielded seven previously undescribed ent-neo-clerodane diterpenoids, laevifins A - G and the known crovatin (3). Structures were established by a combination of spectroscopic methods including HRESIMS, NMR spectroscopy and X-ray crystallography. The absolute configuration of crovatin and laevifins A-G was established by comparison of experimental ECD and theoretical TDDFT ECD calculated spectra. This is the first report on the occurrence of the sesquiterpenoid cryptomeridiol in a Croton species. In vitro cytotoxicity assays on laevifins A, B and G showed moderate activities against the MCF-7 cancer cell line (IC50 102, 115 and 106 μM, respectively) while β-amyrin and acetyl aleuritolic acid showed good anti-inflammatory activity on the LPS-induced NF-κB translocation inhibition in RAW 264.7 cells assay with IC50 values of 23.5 and 35.4 μg/mL, respectively. © 2018 Elsevier Ltd