PHYTOCHEMICAL INVESTIGATION OF XANTHIUM OCCIDENTALE

Abstract

Xanthium occidentale Bert, was phytochemically investigated. Two crystalline sterols were isolated from the unsaponifiable fraction of the light petroleum extract of the plant. The first sterol (0.024 per cent), its molecular formula was established as C₂₈H₄₈O, m. p. 158.5–160.5° C, [α]²⁶ _D +51.8°, and formed an acetyl derivative, m. p. 176–178° C. The second sterol (0.096 per cent), its molecular formula was established as C₂₃H₃₉O₂, m. p. 128–130° C, [α]²⁶ _D – 37.4°, and formed an acetyl derivative, m. p. 120° C. The two isolated sterols do not resemble any of the previously isolated phytosterols. A crystalline triterpenoid (0.1 per cent) was isolated from the ether extract of the plant, its molecular formula was established as C₃₀H₅₀O₅, m. p. 273–276° C (dec), [α]²⁶ _D – 60.4°, formed a tetraacetyl derivative m. p. 159–161° C. Moreover, the N. M. R. analysis of the acetylated material revealed that this triterpenoid contains 5 oxygen atoms in its molecule; 4 of which occurring as 4 alcoholic OH groups, while the fifth O occurring in an ether linkage. A literature survey revealed that this triterpenoid is most probably a new one. A quaternary alkaloid was isolated as its chloride (0.1 per cent) from the alcoholic extract by the reineckate method. Its identity was proved to be choline chloride.

Zusammenfassung

Aus der Fraktion der Unverseifbaren von Xanthium occidentale wurden zwei bisher unbekannte Sterole kristallin isoliert und durch Summenformel, Schmelzpunkt, spezifische Drehung und Acetylderivat charakterisiert. Aus dem Ätherextrakt wurde ein vermutlich bisher unbekanntes kristallines Triterpenoid isoliert und durch chemische und physikalische Daten charakterisiert. Aus dem Alkoholextrakt wurde Cholinchlorid erhalten.