Isolation and spectroscopic characterisation of scopoletin from the chloroform fraction of the whole plant of Iraqi Rhanterium epapposum Oliv.

Rhanterium epapposum Oliv. is a desert plant from the family Asteraceae, widely distributed in Iraq and traditionally utilised for treating skin infections and gastrointestinal disorders, as well as for its insecticidal properties. However, its phytochemical composition, particularly with respect to coumarin constituents, remains insufficiently explored. The present study aimed to isolate and identify a major coumarin compound from the whole plant of Iraqi R. epapposum. The coarse powdered plant material was defatted with n-hexane, extracted by cold maceration with 85 % aqueous methanol and subjected to successive solvent fractionation. The chloroform fraction was selected for further purification based on its phytochemical profile. Thin-layer chromatography revealed a prominent fluorescent spot indicative of a coumarin compound and high-performance liquid chromatography confirmed its presence. The compound was isolated using preparative layer chromatography and obtained as a single major constituent (coded DA10) with a yield of 0.013 %. Structural identification was achieved through combined chromatographic and spectroscopic analyses, including ultraviolet–visible (UV–Vis) spectroscopy, high-performance liquid chromatography (HPLC) spiking, Fourier transform infrared (FTIR) spectroscopy, proton nuclear magnetic resonance (¹H-NMR) spectroscopy and gas chromatography-mass spectrometry (GC-MS), which showed excellent agreement with an authenticated scopoletin standard. The isolated compound DA10 was identified as scopoletin. This study provides the first confirmed isolation and comprehensive characterisation of scopoletin from R. epapposum collected in Iraq. These findings contribute to the phytochemical profiling of the Iraqi chemotype of the species and provide a scientific basis for future investigations on the biological activities and pharmacological potential of the isolated coumarin and other fractions of the plant.