Spring hemlock looper

Scheme 7 summarizes the synthesis of (7JR,llS)-7,ll-dimethylheptadecane (1), the female sex pheromone of the spring hemlock looper (Lambdina athasaria) by Mori [ 18]. Enantiopure alkanes are usually synthesized by coupling enantio-pure building blocks derived from natural products or compounds prepared by asymmetric synthesis. Even among hydrocarbons, chirality is very important for pheromone activity, and in this particular case meso-1 was bioactive, while neither (7R,11R)-1 nor (7S,11S)-1 showed bio activity. 

Lambdina athasaria spring hemlock looper moth... 

I already described the story of the tsetse fly pheromone (117). The female-produced sex pheromone components of the spring hemlock looper moth (Lambdina athasaria) are 7-methylheptadecane and 7,11-dimethylheptadecane (126). After the synthesis of all of their stereoisomers, a mixture of (S)-7-methylheptadecane and (7/ ,llS)-116 (meso-116) was found to be pheromonally active.149... 

Component of the female sex pheromone of the spring hemlock and pitch pine looper moths... 

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