7-Dodecen

Rasmussen L.E.L., Lee T.D., Zhang A., Roelofs W.L., et al. (1997). Purification, identification, concentration and bioactivity of (Z)-7-dodecen-l-yl acetate sex pheromone of the female Asian Elephant, Elephas maximus. Chem Senses 22, 417-438. 

Abstract A relatively small number of mammalian pheromones has been identified, in contrast to a plethora of known insect pheromones, but two remarkable Asian elephant/insect pheromonal linkages have been elucidated, namely, (Z)-7-dodecen-1-yl acetate and frontalin. In addition, behavioral bioassays have demonstrated the presence of a chemical signal in the urine of female African elephants around the time of ovulation. Our search for possible ovulatory pheromones in the headspace over female African elephant urine has revealed for the first time the presence of a number of known insect pheromones. This search has been facilitated by the use of a powerful new analytical technique, automated solid phase dynamic extraction (SPDE)/GC-MS, as well as by novel macros for enhanced and rapid comparison of multiple mass spectral data files from Agilent ChemStation . This chapter will focus on our methodologies and results, as well as on a comparison of SPDE and the more established techniques of solid phase microextraction (SPME) and stir bar sorptive extraction (SBSE). 

The Asian elephant has farnesol, 4-ethylphenol and 4-methylphenol in its temporal gland secretion while the African elephant has only 4-methylphenol. Farnesol levels are inversely related to testosterone levels (Rasmussen and Perrin, 1999). Preovulatory female urine contains (Z)-7-dodecen-l-yl acetate (Rasmussen etal, 1996). 

The sex pheromones of four Plusiinae species in the family Noctu-idae namely, Ctenoplusia albostriata (CA), Macdunnoughiapurissima (MP), Syngrapha ain (SA) and Diachrysia stenochrysis (DS), were identified. CA females produced ( )-5-decenyl acetate (1), ( )-7-dodecenyl acetate (II), and (.Z)-7-dodecen-l-ol (III) in a ratio of 2 100 13. The MP females produce II, III, and ( )-5-dodecenyl acetate (IV) in a ratio of 100 80 20. Compounds 11 and 111 were also identified from the SA females, whereas the DS females produced just one active compound, (.Z)-7-decenyl acetate. DS species were the first Plusiinae species identified using only the oo3-compound and none of the oo5-compounds, such as II and III that are common components of Plusiinae pheromones. 

Erste Anzeichen von Photoreduktion verbriickter Olefine zeigten sich bereits bei der Bestrahlung von Norbomen in Aceton 34) und spater bei den Kohlenwasserstoffen der Tetracyclo(6.2.1.13.602.7)dodecen-4 42)-Reihe. 

Shorthand notation for pheromone molecules for example, (Z)-7-dodecen-l-yl acetate is shortened to Z7-12 OAc where the Z denotes the double bond configuration (Z or E), 7 the double bond position, 12 the number of carbons in the chain, OAc indicates the functional group as an acetate ester. Aid = aldehyde, Co A = coenzyme A, D = deuterium, Epox = epoxide, He = hydrocarbon, me = methyl group, OH = alcohol. 

Z)-7-Dodecen-l-yl acetate, component of the sex attractant of the female elephant and numerous insects... 

Pheromones are also important in mammals, although many fewer have been identified. As one example, (Z)-7-dodecen-l-yl acetate has recently been identified in the urine of female elephants when they are in heat. This ester elicits a specific sexual response in male elephants. Interestingly, this same ester is part of the pheromone mixture that many insects, especially moths, use as a sexual attractant. 

First identified in Asian elephants during a headspace analysis of volatiles collected from secretions of the musth temporal gland of adult males,156 frontalin (52) is a bicyclic ketal, which is structurally reminiscent of the male mouse priming pheromone component 3,4-dehydro-ara-brevicomin (37). Frontalin (52), Z-7-dodecen-l-yl acetate (51), was already known because of its chemosensory role in the insect world it is an aggregation pheromone in bark beetles.157 Interestingly, the ratio of the two enantiomers of frontalin (52) changes with age and stage of musth and elicits different behavioral responses.158... 

The structural similarities between the putative mammalian chemosignals and the pheromones identified previously in the insect world are quite striking. The farnesenes [257, 258] (entries 66, 67) and 2-heptanone [259] (entry 68) have been implicated previously as insect pheromones. There is only one double bond distinguishing the male mouse pheromone 3,4-dehydro-exo-brevicomin (entry 65) from a bark beetle pheromone [260], brevicomin. In addition, the elephant pheromone (Z)-7-dodecen-l-yl acetate (entry 69) is also known to be an insect pheromone [259]. While the potency may not compare to the insect system, investigators are beginning to find evidence that many mammals ranging from pigs to elephants can have a pheromone-type response to a sniff of secretions even humans appear to respond [261],... 

Diphenyl oxide+7-dodecene [BMIM]C1/A1C13 [53] Monododecyl diphenyl - 90 -... 

Karlson and Liischer anticipated that species would not necessarily have exclusive use of a particular molecule as their pheromone. We now know many examples of shared use of molecules (Kelly 1996 Wyatt 2003, 2010). One of the most spectacular is the way that the female Asian elephant shares its small molecule sex pheromone, (Z)-7-dodecen-l-yl acetate, with some 140 species of moth (Rasmussen et al. 1996). Because the moths use defined combinations of molecules, of which (Z)-7-dodecen-l-yl acetate is just one, there is not likely to be confusion between elephants and moths. Because the defined combination is different for each moth species there is no confusion between the moth species in cases where the combination is the same, the species call with their pheromones at different times or have nonoverlapping habitats. 

Elephants and moths are unlikely mates, so scientists and the general public were surprised when it was discovered that one of the world s largest living land animals, the Asian elephant Elephas mctximus), shares its female sex pheromone with some 140 species of moth (Rasmussen et al., 1996). The compound is a small, volatile molecule (Z)-7-dodecen-l-yl acetate. The shared use of a compound as a signal illustrates a relatively common phenomenon of independent evolution of particular molecules as... 

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