Two isomeric glycoside sesquiterpenes from Machaeranthera tanacetifolia

• Published in: Phytochemistry (Oxford) 1998-08, Vol.48 (7), p.1221-1224
• Main Authors: Martínez-Vázquez, Mariano, García-Argáez, Aída N., Bueno, Juventino López, Espinosa, Georgina, Calderón, JoséS.
• Format: Article
• Language: English
• Subjects: Asteraceae; Biological and medical sciences; chemical constituents of plants; Chemical constitution; chemical structure; Fundamental and applied biological sciences. Psychology; leaves; nuclear magnetic resonance spectroscopy; Plant physiology and development; sesquiterpenoids; spectral analysis
• ISSN: 0031-9422; 1873-3700
• DOI: 10.1016/S0031-9422(97)00819-4

From the aerial parts of Machaeranthera tanacetifolia the known 12-hydroxy- ent-kauren-16-en-19-oic acid and the two previously unknown (−)-11-O-α- d-arabinopyranosyl - and (+)-11-O-β- l-arabinopyranosyl-β-eudesmol were isolated From the aerial parts of Machaeranthera tanacetifolia the known 12-hydroxy- ent-kauren-16-en-19-oic acid and the two previously unknown (−)-11-O-α- d-arabinopyranosyl-β-eudesmol and (+)-11-O-β- l-arabinopyranosyl-β-eudesmol were isolated. The structure elucidation of these compounds was based on spectroscopic and chemical evidences. (+)-11-O-β- l-Arabinopyranosyl-β-eudesmol was fully characterized by X-ray analysis of its peracetate derivative. According with these results, we propose that the previously reported (+)-11-O-α- l-arabinopyranosyl-β-eudesmol and 11-O-α- d-arabinopyranosyl-β-eudesmol are identical to (+)-11-O-β- l-arabinopyranosyl-β-eudesmol .