Sesquiterpene Glycosides from Calendula persica

Area of Science:

• Phytochemistry
• Natural Products Chemistry
• Organic Chemistry

Background:

• Calendula persica is a plant species with potential medicinal properties.
• Sesquiterpene glycosides are a class of natural compounds with diverse biological activities.
• Previous research on Calendula species has identified various bioactive compounds.

Purpose of the Study:

• To isolate and elucidate the structures of compounds from the polar fractions of Calendula persica aerial parts.
• To identify novel sesquiterpene glycosides and their structural origins.
• To characterize the glycosidic components present in the extract.

Main Methods:

• Extraction of aerial parts of Calendula persica.
• Isolation of polar fractions.
• Purification of compounds using chromatographic techniques.
• Structure elucidation using high-field Nuclear Magnetic Resonance (NMR) spectroscopy, including 1D and 2D NMR experiments.

Main Results:

• Eight sesquiterpene glycosides were isolated and characterized.
• Five glycosides were derived from viridiflorol.
• Two glycosides were derived from beta-eudesmol.
• One glycoside was derived from 4alpha-hydroxygermacra-1(10)E,5E-diene.
• Fucopyranosides and chinovopyranosides were identified as additional components.

Conclusions:

• The study successfully identified eight unique sesquiterpene glycosides from Calendula persica.
• The structural analysis confirmed the presence of fucopyranoside and chinovopyranoside moieties.
• High-field NMR techniques proved effective for the detailed structural elucidation of these complex natural products.