Acetylenes carrots

Bentley, R. K., D. Bhattacharjee, Sir R. H. Jones, and V. Thaller Natural Acetylenes. Part XXVIII. C-17-Polyacetylenic Alcohols from the Umbellifer Daucus carota L. (Carrot) Alkylation of Benzene by Acetylene (Vinyl) Carbinols in the Presence of Toluene-/ -sulphonic Acid. J. Chem. Soc. Section C (London) 1969, 685. 

A mixture of volatiles from carrot Daucus carota, Apiaceae) is responsible for oviposition by females of the carrot fly Psila rosae). Among these are the phenylpropanoids. E-methyleugenol, -asarone, a prenylated coumarin, osthol (31), bergapten (18), xanthotoxin (19), and an acetylenic compound, falcarindiol (Harbome, 1986). No single component of the mixture is responsible for the behavior of the fly. 

The most common acetylenes isolated from food plants are aliphatic acetylenes (Figures 5.1 and 5.3, and Table 5.1). Aliphatic acetylenes of the falcarinol-type (especially compounds 1, 2, 4 and 5) are widely distributed in the Apiaceae and Araliaceae plant families (Bohlmann et al. 1973 Hansen and Boll 1986), and consequently nearly all acetylenes found in the utilized/edible parts of food plants of the Apiaceae, such as carrot, caraway (Carum carvi), celery, celeriac (Apium graveolens var. rapaceum), fennel (Feonkulum vulgare), parsnip (Pastinaca sativa) and parsley are of the falcarinol-type... 

Allergic contact dermatitis from common vegetables of the Apiaceae, such as carrots, celery and parsley is known (Murdoch and Demster 2000 Machado et cd. 2002) but rare, probably due to their relatively low concentrations of allergenic acetylenes compared with ornamental and wild plant species (Hausen 1988), or possibly a desensitizing effect of oral intake. 

Barley, G.C., Jones, E.R.H. and Thaller, V. (1988) Crepenynate as a precursor of falcarinol in carrot tissue culture. In J. Lam, H. Breteler, T. Arnason et al. (eds). Chemistry and Biology of Naturally-Occurring Acetylenes and Related Compounds (NOARC). Elsevier, Amsterdam, pp. 85-91. 

Bentley, R.K., Bhattacharjee, D., Jones, E.R.H. et al (1969a) Natural acetylenes. Part XXVIII. Ci7-Polyacetylenic alcohols from the UmbeUifer Daucus carota L. (carrot) Alkylation of benzene by acetylenyl(vinyl)carbinols in the presence oftoluene-p-sulphonic acid. /. Chem. Soc. (C), 685-688. 

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