Minor alkamides from Heliopsis longipes S.F. Blake (Asteraceae) fresh roots

• Published in: Phytochemistry letters 2011-09, Vol.4 (3), p.275-279
• Main Authors: López-Martínez, Sugey, Aguilar-Guadarrama, A. Berenice, Rios, María Yolanda
• Format: Article
• Language: English
• Subjects: Alkamides; Asteraceae; Heliopsis longipes; Linear dihydroxyalkamides
• ISSN: 1874-3900; 1876-7486
• DOI: 10.1016/j.phytol.2011.04.014

From the fresh roots of Heliopsis longipes three new minor alkamides: longipinamide A ( N-isobutyl-8,10-diynoic-3Z-undecenamide), longipenamide A ( N-isobutyl-syn-8,9-dihydroxy-2E,6Z-decadienamide) and longipenamide B ( N-isobutyl- syn-6,9-dihydroxy-2E,7E-decadienamide); three known alkamides, and other known compounds were isolated. This is the first report of the isolation of linear dihydroxyalkamides as natural products. [Display omitted] ► The fresh roots of Heliopsis longipes yielded three new minor linear alkamides. ► Affinin, the major isolated alkamide from this natural source was obtained in 45.23% yield. ► The minor alkamides were isolated between 0.1 and 0.21% yield. ► This is the first report of the isolation of linear dihydroxyalkamides as natural products. From the fresh roots of Heliopsis longipes three new minor alkamides: longipinamide A ( N-isobutyl-8,10-diynoic-3 Z-undecenamide), longipenamide A ( N-isobutyl- syn-8,9-dihydroxy-2 E,6 Z-decadienamide) and longipenamide B ( N-isobutyl- syn-6,9-dihydroxy-2 E,7 E-decadienamide); three known alkamides: affinin (spilanthol, N-isobutyl-2 E,6 Z,8 E-decatrienamide), N-isobutyl-2 E,6 Z-decadienamide and N-isobutyl-2 E-decenamide; and 11 other known compounds were isolated. The structures of the three new minor alkamides were established by 1D and 2D NMR spectroscopy including 1H, 13C, DEPT, COSY, HSQC, and HMBC experiments, as well as by EI and FAB + mass spectrometry. To our knowledge, this is the first report of the isolation of linear dihydroxyalkamides as natural products.