3,5-Tetradecadienoic acid

The female produced sex pheromone of the black carpet beetle, Attagenus unicolor (formerly called A. megatoma or A. piceus) has been identified as early as 1967 to be (3 ,5Z)-3,5-tetradecadienoic acid, megatomoic acid 106 [204,205] (Scheme 12). The (3Z)-isomer of megatomoic acid was found to be the major male attracting component in the female produced pheromone of A. brunneus (formerly A. elongatulus) [206]. 

E,Z)-3,5-tetradecadienoic acid as a sex attractant (55). The sexual releaser emitted by females of the furniture carpet beetle, Anthrenus flavipes, has been identified as (Zj-3-decenoic acid (56). The (Z)-isomer is about 20X more active than the (E)-isomer. 

Pheromones of insect species in the order Coleoptera are characterized by considerable structural diversity. Unlike the lepidopterous sex pheromones, which are nearly all tatty acid derivatives, coleopterous sex pheromone structures range in complexity from the relatively simple 3,5-tetradecadienoic acid of the black carpet beetle to the tricyclic terpenoid, lineatin, of the striped ambrosia beetle. While the sex pheromones of many beetles consist of mixtures of compounds that act synergistically to elicit a behavioral response, other Coleoptera species appear to use only a single compound for chemical communication between the sexes. In the latter case the compound usually has at least one chiral center and chirality plays a major role in determining pheromone specificity. 

Females of the black carpet beetle, Attagenus megatoma, produce the sex pheromone ( , Z)-3,5-tetradecadienoic acid 301). An important related species, A. elongatulus, has also been shown to produce a sex pheromone 302) and a major attracting component has been identified as (Z,Z)-3,5-tetradecadienoic acid 303). 

Rodriguez S, Clapes P, Camps F, Fabrias G. Stereospecificity of an enzymatic monoene 1,4-dehydrogenation reaction conversion of (Z)-ll-tetradecenoic acid into ( , )-10,12-tetradecadienoic acid. J. Org. Chem. 2002 67 2228-2233. 

Q3. Palmitic acid is converted to ( )-11 -hexadecenoic acid, then chain-shortened to 9-hexadecenoic acid, and again desaturated by a All-desaturase to (9 , 1 l )-tetradecadienoic acid. The remaining steps are obvious. 

Rodin, J. O., M. A. Laeffer, and R. M. Silverstein Synthesis of trans-3yCis-5-tetradecadienoic acid (megatomoic acid), the sex attractant of the black carpet beetle, and its geometric isomers. J. Org. Chem. 35, 3152—3154 (1970). 

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