Natural acetylenes. Part XLIX. Polyacetylenes from Dahlia scapigera(A. Dietr.) Link and Otto var. scapigera f. scapigera and some Dahlia hybrids

Abstract

Examination of the above Dahlia species revealed the presence of 8 polyacetylenic compounds of which the C₁₆ ene-diyn-ene alcohol (XXXII) and its acetate were new. In representatives of the main garden varieties 36 poly-MeCH[graphic omitted]CH·[CC]₂·CH[graphic omitted]CH·CH(OH)·CH(OH)·CHCH₂(XVIII), MeCH[graphic omitted]CH·[CC]₂·[CH[graphic omitted]CH]₂·CH(OH)·CH₂·CH₂OH (XXVIII), MeCH[graphic omitted]CH·[CC]₂·[CH[graphic omitted]CH]₂·[CH₂]₄·CH₂·OH (XXXII), Me[CC]₃·[CHCH]₂·CH(OH)·[CH₂]₃·CHCH₂(XXXVI), acetylenes were detected, including the new (XVIII), (XXVIII), and (XXXVI) and their acetates. Seasonal variations of the content were noted. The C₁₇ alcohol (XXXVI) and the C₁₆ alcohol (XXXII) were synthesised; the latter and the corresponding C₁₄ compound by novel routes.