Z-ll-Tetradecenyl acetate

The sex pheromone of the South American tortricid moth, Argy-rotaenia sphaleropa, was identified as a mixture of (Z)-l 1-tetradecenal, (Z)-ll,13-tetradecadienal, (Z )-ll-tetradecenyl acetate and (Z )-ll,13-tetradecadienyl acetate in the ratio of 1 4 10 40. Best results for trapping were obtained with mixtures of (Z )-ll-tetradecenal and (Z )-ll,13-tetradecadienal in the ratio of 1 4 to 1 9. ... 

Prbesner 242,243) found specific receptor cells in the male antennae sensilla trichodea for the sex pheromones of two moth species, Z-9-tetradecenyl acetate (48) in Adoxyphies orana and Z-ll-tetradecenyl acetate (49) and Z-9-tetradecenyl acetate (48) in Eulia ministrana, Z-ll-tetradecenyl acetate (49) and Z-9-tetradecenol (50) were also isolated from A, orana. 

Z)-9-tetradecenyl acetate, which is used in the blends of 223 lepi-dopteran species and (Z)-ll-tetradecenyl acetate (Figure 3.23) used by 214 species. Some further examples of lepidopteran pheromones are shown in Figure 3.23. Bombykol, the sex pheromone of the silkworm moth Bombyx mori (Plate 2) was the first pheromone isolated and identified, in an effort that took many years of work (Butenandt, Beckmann, Stamm and Hecfcer, Zeitschrift fur Naturforschung, 1959,14b, 283). It is not easy to see how bombykol could be biosynthesized by use of a A11-desaturase. Indeed it is made in the insect from palmitic acid, which is converted to (Z)-ll-hexadecenoic acid, and then an unusual 10,12-desaturase converts that into (10 , 12Z)-10,12-hexadecadienoic acid. 

The suggestion that the sex pheromone composition of the oak leaf roller was dependent to a large extent on diet was made 82,475,476) and refuted 477, 478). It is now generally accepted that the sex pheromone of this tortricid moth species is a specific blend (67 33) of E)- - and (Z)-ll-tetradecenyl acetates 477). It is also accepted that in this species this ratio is not influenced by diet 478). However, the effects of diet on the amount of pheromonal compounds have been suggested for the summer fruit tortrix moth 479), the gypsy moth 480) and the smaller tea tortrix moth 481). 

Identification of compounds in volatiles collected from hunting M. cornigera revealed three common components of moth sex pheromone blends (Z)-9-tetradecenal, (Z)-9-tetradecenyl acetate, and (Z)-ll-hexade-cenal [while there was insufficient material for mass spectrometry, gas chromatographic retention time evidence suggests that (Z)-ll-hexadece-... 

FIGURE 2 Relative proportions of three identified components of M. comigera spider volatiles (47). The variation in the ratios suggests that spiders change the moth-attracting blends they produce. Z11-16 AL, (Z)-ll-hexadecenal Z9-14-.AC, (Z)-9-tetradecenyl acetate Z9-14 AL, (Z)-9-tetradecenal. 

Fig. 4.7. Volatiles identified from the bolas spider Mastophora cornigera and Mastophora hutchinsoni (15-19) and the pheromone components of Tetano-lita myenesalis (20, 21). 15, (Z)-9-Tetradecenal 16, (Z)-9-tetradecenyl acetate 17, (Z)-ll-hexadecenal 18, (Z)-ll-hexadecenyl acetate 19, (9Z,12F)-9,12-tetradecadienyl acetate 20, (3Z,6Z,9Z)-3,6,9-henicosatriene 21, (3Z,9Z)-(6S, 1R) ...

Tertiary pheromonal blends have been identified in two noctuid moths. The red bollworm, Diparopsis castanea, emits dodecyl acetate, (E)-9-dodecenyl acetate, 11-dodecenyl acetate, and (E)-9,ll-dodecadienyl acetate as a sex pheromone, whereas Spodoptera littoral is utilizes a blend made up of tetradecyl acetate, (E)-9-tetradecenyl acetate, (E)-ll-tetradecenyl acetate, and (Z,E)-9,ll-tetradecadieny1 acetate (89). For both species, the conjugated dienes are the most potent olfactory stimulants. 

The extent of pheromone degradation under field conditions was investigated with a microencapsulated formulation containing a saturated hydrocarbon and acetate (octadecane and tetradecyl acetate (14 Ac)), the corresponding monounsaturated hydrocarbon and acetate ((Z)-4-octadecene and (Z)-9-tetradecenyl acetate (Z9-14 Ac)) and a diunsaturated acetate ((Z,S )-9,ll-tetradeca-dienyl acetate (ZE9,ll-14 Ac)), chosen so that all the components had similar volatilities. On exposure to sunlight, loss of the diene was more rapid than loss of the monounsaturated components which in turn disappeared faster than the saturated components (Fig. 1). All components disappeared at a similar, slower rate when shielded from direct sunlight. 

Figure 3.21 Biosynthesis of the sex pheromone of A. velutinana. It is a mixture of (Z)-and fE)-ll-tetradecenyl acetate in an isomer ratio of 92 8...

The sex attractant produced by the female clover cutworm, Scoto-gramma trifolii, is a mixture of (Z)-ll-hexadecenyl acetate and (Z)-ll-hexadecenol 288). A mixture of these two compounds containing about 10% Zll-16 OH has proved to be most attractive 289, 290) while 20—25% Z11-16 OH decreases the catch of males appreciably 290). Adult males of the glassy cutworm, Crymodes devastator, are attracted by traps baited with equal parts of (Z)-ll-hexadecenyl acetate, (Z)-ll-hexadecenal and (Z)-7-dodecenyl acetate 291). No other species were trapped by this mixture. The addition of small quantities of either (Z)-11-hexadecenol or (Z)-9-tetradecenyl acetate completely inhibited attrac-tancy in the field. As a result of field tests, Underhill et al. 292) have recently found that alkenals may be as important in lepidopteran sex attractants as the acetates and alcohols. 

However, the components of the pheromone of a butterfly are known to give different amplitude EAG s (359). Grant (360) found that pheromones from different species elicit EAG s of similar amplitude in a common recipient. EAG s of similar amplitude were obtained when the antenna of the armyworm, Pseudaletia unipunctata, was stimulated with the male s known pheromone components, benzaldehyde, benzyl alcohol and benzoic acid, or with the related aromatic compounds, 2-phenyl-ethanol and benzyl acetate (361). The antennal response of male European corn borer moths, Ostrinia nubilalis, to their two pheromone components, (Z)- and ( )-ll-tetradecenyl acetates has recently shown that repetitive stimulation with one of the isomers results in adaptation which affects the amplitude of response in subsequent tests to both compounds (362). 

Klun et al. 267), in studies at Ankeny, Iowa, on the European corn borer, found that males were only weakly attracted to highly purified (Z)-l 1-tetradecenyl acetate while the red-banded leafroller was not attracted at all to this compound. However, if small amounts of the E-isomer were added to the Z-isomer, both species were strongly attracted, yet neither species showed any response to the E-isomer alone. It was primarily after this study that it was realized that many lepidopteran sex pheromones are specific blends of the E- and Z-isomers of long chain acetate esters. The results on the Iowa European corn borer have recently been confirmed by more sophisticated separation techniques for chemically complex mixtures 268) and a number of specific ratios of the nonpheromone, (Z)- and ( )-ll-tridecenyl acetate, have been studied in field trials on the red-banded leafroller 269). 

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