Acetylenic acids mosses

Three acetylenic acids present in the lipids of mosses (18 3 6a9cl2c, 18 4 6a9cl2cl5c and 20 3 8allcl4c) are clearly related to the corresponding polyene acids. 

Acetylenic acids occur in a number of rare seed oils and in some mosses. No oil containing acetylenic acids is available commercially. 

Dicranin (= Z>Z>Z> Octadeca- 6-yne-9,12,15-trienoic acid) (acetylene) Dicranum scoparium (moss) (Dicranaceae) [aerial] SLOX [antibacterial]... 

In addition to the normal ethylenic double bonds, some fatty acids possess acetylenic bonds. They have been found in rare seed oils and some moss species. 

MOSS GREEN (12002-03-8) Contact with strong oxidizers chlorine, fluorine, peroxides may eause fire and explosions. Incompatible, or may form highly sensitive and unstable materials such as acetylides with acetylene, glycidol, hydrazine, hydrazinium nitrate, hydrazinium perchlorate, lead azide, mercurous chloride, nitropropane, picric acid, silver nitrate. 

The third group of acetylenic compounds is not related clearly to the first two. Acetylenic linkages are occasionally introduced into compounds of diverse biosynthetic origin such as sesquiterpenes, tetraterpenes, and amino acids (Fig. 3.12). These compounds are found in unrelated plant families, among them the Annonaceae, Cupressaceae, Euphor-biaceae, Fabaceae, Lauraceae, Myoporaceae, Sapindaceae, Simaroubaceae, Sterculiaceae, Valerianaceae, and certain algae and mosses. 

Over 600 naturally occuring compounds witb acetylenic bonds (triple bonds) have been characterized (Bohlmann et al, 1973). Previous in-vivo studies, from mosses accumulating acetylenic fatty acids, indicate that the acetylenic bond is formed by the substraction of two hydrogen atoms from a double bond (Kohn et al, 1994). 

Kohn, G., Hartmann, E., Stymne, S. and Beutelmann, P. (1994) Biosynthesis of acetylenic fatty acids in the moss Ceratodon purpureus (Hedw.) Brid., J. Plant Physiol. 144, 265-271. 

In certain species of moss, there are polyunsaturated fatty acids with acetylenic bonds separated from double bonds by single methylene groups. It proved possible to use separation factors and FCL values to predict the retention times of these compounds as with the more common range of unsaturated fatty acids as described above [441]. Distinctive... 

AN UNCOMMON PATHWAY IN THE BIOSYNTHESIS OF ACETYLENIC FATTY ACIDS IN MOSSES... 

The moss Ceratodon purpureas (Hedw.) Brid. contains large amounts of the acetylenic fatty acids 9,12-octadecadien-6-ynoic acid [18 2A] and 6,9,12-octadecatrien-6-ynoic acid [18 3A], which are in close structural relationship to the common fatty acids lino-leic acid [18 2(n-6)] and oc-linolenic acid [18 3(n-3)], and which are obviously restricted to the triacylglycerol fraction [2]. 

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