INTEGRATED NMR, FTIR, AND MASS SPECTROMETRIC APPROACH TO THE STRUCTURAL ELUCIDATION OF A HEPTACYCLIC METHOXY- AND METHYLPEROXY-SUBSTITUTED COMPOUND FROM Lactuca taraxacifolia
DOI:
https://doi.org/10.33003/fjs-2026-1007-5154Keywords:
NMR, FTIR, MASS SPECTROMETRIC APPROACH, HEPTACYCLIC METHOXY, METHYLPEROXY-SUBSTITUTED COMPOUND, LACTUCA TARAXACIFOLIAAbstract
This study reports the extraction, isolation, and spectroscopic characterization of compound SB2 from the aerial parts of Lactuca taraxacifolia. Pulverized plant material was extracted with chloroform and successively partitioned using n-hexane, trichloromethane, ethyl ethanoate, and methanol. The trichloromethane fraction was subjected to silica gel column chromatography using a gradient solvent system of n-hexane and ethyl ethanoate (100:0–0:100, v/v). Fractions were monitored by thin-layer chromatography using n-hexane/ethyl ethanoate (9:1, v/v) as the mobile phase, yielding SB2 as a green oily liquid with a single spot (Rf = 0.42). Structural characterization was carried out using FTIR, ¹H NMR, ¹³C NMR, COSY, and GC–MS analyses. GC–MS revealed a molecular ion peak at m/z 530.7804 corresponding to the molecular formula C₃₆H₅₀O₃. Spectroscopic data indicated the presence of aromatic and aliphatic domains together with oxygenated functionalities including methoxy and methylperoxy groups. Although overlapping NMR signals limited definitive structural assignment, the combined GC–MS, FTIR, and NMR data support a structurally complex oxygenated aromatic–aliphatic compound with possible polycyclic features. The findings contribute to the phytochemical knowledge of Lactuca taraxacifolia.
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Copyright (c) 2026 Benedict C. Anyanwu, Chidi P. Njoku, Canice U. Silas, Onyinyechi U. Akoh, Bright C. Onyekwere, Gogo C. Anyanwu
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