Very-long-chain 1,2- and 1,3-bifunctional compounds from the cuticular wax of Cosmos bipinnatus petals.
Four uncommon classes of very-long-chain compounds were identified and quantified in the petal wax of Cosmos bipinnatus (Asteraceae). The first two were homologous series of alkane 1,2-diols and 1,3-diols, both ranging from C20 to C26. The upper and lower petal surfaces contained 0.11 and 0.09 μg/cm(2) of 1,2-diols, respectively. 1,3-Diols were present at quantities one order of magnitude less than the 1,2-diols. Both series had similar chain length distributions, with 6-20%, 59-73% and 20-31% of the C20, C22 and C24 diols, respectively. The other two compound classes were primary and secondary monoacetates of C20-C24 1,2-diols. The monoacetates had chain length profiles similar to the free 1,2-diols, and amounted to 0.04 and 0.09 μg/cm(2) on the adaxial and abaxial sides, respectively. Methods were developed to minimize acyl migration during monoacetate isomer analyses. The ratios of diol 1-acetates to diol 2-acetates averaged close to 3:5, and thus opposite to the chemical equilibrium ratio of 7:3.
Department of Botany, University of British Columbia, Vancouver, Canada.
Christopher
C
Buschhaus
Chen
C
Peng
Reinhard
R
Jetter
D000438:Alcohols / Q000138:chemical synthesis / Q000737:chemistry* / Q000302:isolation & purification; D000473:Alkanes / Q000737:chemistry* / Q000302:isolation & purification; D019659:Asteraceae / Q000737:chemistry*; D035264:Flowers / Q000737:chemistry*; D015394:Molecular Structure; D014885:Waxes / Q000737:chemistry*
D000438:Alcohols; D000473:Alkanes; D014885:Waxes