Polyacetylenverbindungen, 269 Neue NS‐Isobutylamide aus Heliopsis‐Arten

Abstract

Die Untersuchung von zwei Heliopsis-Arten ergibt drei neue, hochungeslttigte N-lsobutylamide von Cl8-Acetylencarbonsauren und ein weiteres Lignan, das nahe verwandt ist mit friiher isolierten Derivaten. Polyacetylenic Compounds, 269 *). -New N-lsobutylamides From Heliopsis SpeciesThe investigation of two Heliopsis species afforded in addition to known compounds three new highly unsaturated N-isobutylamides of CIE-acetylenic carbonic acids and a further lignane closely related to derivatives which were isolated previously.

Alkamides: Structural Relationships, Distribution and Biological Activity1

“…However, they may be expected to be closely related to, or even identical, with those amides recently isolated from H. hehianthoides (26).…”

“…More recently, a group of C18-amides has been isolated from Heliopsis species (Tab. II) whose olefinic and acetylenic patterns resemble those of some derivatives shown in Scheme 4 (26). In contrast to the C18-compounds found in Achillea lycaonica, they are characterized by a high degree of unsaturation (39)(40)(41).…”

“…(18). With the exception of the amide 21 + 42, which was isolated in small amounts from the Heliantheae genus Heliopsis (26), all other derivatives mentioned above appear to be typical for the Anthemideae. Moreover, with regard to fruit morphological characters, the accumulation of amides suggests close relationships between Achillea, Leucocyclus and Anacyclus (55) as well as between Chamaemelurn and Cladanthus.…”

“…systems (23)(24)(25)(26). From Echinacea angustifolia DC., E. purpurea (L.) Moench and Spilanthes alba L'Hérit., the acetylenic amides 27-30 have been isolated which deviate from structurally related derivatives by a Z-oriented double bond conjugated with the carbonyl (amide) group (24,25).…”

Highly Unsaturated Isopentyl Amides from Achillea wilhelmsii

“…Further characteristic differences are shown by 6-H and 7-H; 8: 6-H at 6.58 ppm (dd, appearing as a pseudo t with J= 11 and 11 Hz, ß-position to the triple bond), 7-H at 5.66 ppm (d, J= 11 Hz); 9: 6-H at 6.77 ppm (dd,_/= 15 and 11 Hz), 7-H at 5.83 (d,J= 15 Hz). Asimilar influence of the C=C anisotropy on the chemical shifts of the olefinic protons of an yn-diene partial structure [relatively large downfield shift for the proton y to C = C in the (Z,E)-isomer and for ß in the (£,£)-isomer] was also observed for other alkamides (21,22). The isopentyl amide resonances are the usual ones (see 1).…”