Lignans and neolignans from Stelleropsis antoninae

Area of Science:

• Phytochemistry
• Natural Products Chemistry
• Pharmacognosy

Background:

• Stelleropsis antoninae, an herbaceous plant from Iran, belongs to the Thymelaeaceae family, known for pharmacologically active lignans and neolignans.
• Previous phytochemical investigations of S. antoninae have not been reported.
• Lignans and neolignans are classes of phenolic compounds with diverse biological activities.

Purpose of the Study:

• To isolate and identify the main lignan and neolignan compounds from the methanol extract of Stelleropsis antoninae.
• To compare the isolated compounds with those found in other Thymelaeaceous species.
• To contribute to the phytochemical knowledge of S. antoninae.

Main Methods:

• Extraction of aerial parts of S. antoninae using methanol.
• Isolation and purification of compounds using Column Chromatography (CC) and High-Performance Liquid Chromatography (HPLC).
• Structure elucidation of isolated compounds using spectroscopic techniques: 1H-NMR, 13C-NMR, HMBC, HMQC, H-H COSY, and Mass Spectrometry (MS).

Main Results:

• Four lignans were isolated and identified: syringaresinol (1), syringaresinol 4-O-β-D-glucopyranoside (4), syringaresinol 4-O-β-D-glucopyranosyl-(1→6)-β-D-glucopyranoside (5), and liriodendrin (6).
• Two neolignans were isolated and identified: 5-methoxylariciresinol 4'-O-β-D-glucopyranoside (3) and dehydrodiconiferyl alcohol 4-O-β-D-glucopyranoside (2).
• Syringaresinol and its glucosides were identified as major lignans, while lariciresinol and coniferyl alcohol derivatives were identified as major neolignans.

Conclusions:

• Syringaresinol, a known bioactive compound, and its glucosides are the principal lignans in Stelleropsis antoninae.
• Lariciresinol and coniferyl alcohol derivatives represent the main neolignans found in this species.
• The study provides the first report on the isolation and identification of lignans and neolignans from S. antoninae.