Octadecatrienal

Tall oil fatty acids consist of resin acids (25% to 30%) and of a mixture of linolic acid, conjugated Cig fatty acids (45% to 65%), oleic acid (25% to 45%), 5,9,12-octadecatrienic acid (5% to 12%), and saturated fatty acids (1% to 3%). Resin acids are abietinic acid, dehydroabietic acid, and others. Properties of fatty acids are shown in Table 6-1. 

Institut fur allgemeine Botanik Universitat Mainz SaarstraBe 21 D-55122 Mainz Telefon (06131) 39-3326 Telefax (06131) 39-3787 9,12-Octadecadien-6-ynoic acid 9,12,15-Octadecatrien-6-ynoic acid 9-Octadecen-6-ynoic acid... 

Octadecadien-6-ynoic acid 9,12,15-Octadecatrien-6-ynoic acid... 

There are several potential examples of bond homoconjugation in the literature, of which the 3,5-dehydrophenyl cation, 14, is probably best known (see also Figure 2)33. If the sp2 hybrid orbitals at position 1, 3 and 5 point toward the centre of the ring, they can overlap and form a homoconjugative 2-electron-3-centre system. In plane overlap between 71 orbitals, cr-type overlap can also be expected for tetracyclo-[8.2.2.225.269]-l,5,9-octadecatriene, 15, in which three double bonds are kept face to face by frames made out of cyclohexane rings34. Finally, [3]pericyclyne and 1,5,9-cyclododeca-triyne could be considered to be better examples for [Pg.353]

Goller, S., Szocs, G., Francke, W. and Schulz, S. (2007). Biosynthesis of (3Z,6Z,9Z)-octadecatriene the main component of the pheromone blend of Erannis bajaria (Lepidoptera Geometridae)../. Chem. Ecol., 33, 1505-1509. 

Sphingatrienes also occur naturally but in minor amounts. Sphingomyelin isolated from squid nerve and from starfish contains a branched, triunsaturated sphingoid base, 2-amino-9-methyl-4 , 8 , 10 -octadecatriene-l,3-diol (10), and glycosphingolipids from starfish contain the same long-chain base without the methyl branch (9). 

Bromo-9,13,17-octadecatriene-5,7,15-triynoic acid, B-20052 12-Bromopalisadin B, in P-10003 6-Bromo-5,9-pentacosadienoic acid, B-3008 5... 

Figure 2. 1- Cyclooctene conversion 2- 1,9-tetradecadiene 3- 5,13-octadecadiene 4- 1,9-decadiene 5- 1,9,17-octadecatriene...

Figure 4. 1- Cyclooctene conversion 2- l,9E,17-octadecatriene 3- 5E,13E-octadecadiene 4- 5Z,13E-octadecadiene 5- 5Z,13Z-octadecadiene.

Linolenic Acid (8 11 14-Heptadecatriene-l-carboxylic add, 9 12 15 octadecatrienic acid)... 

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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