Bark beetles pheromones

The third component of the elm bark beetle pheromone (p T 4) is a-cubebene (34) which the beetle takes from the tree. Simple disconnections lead to ketone (35). What disconnection would you suggest next ... 

Regiospecific Mono-Hydroxyalkylation of Dilithiated Lsopropenyiacetylene with Isovaleraldehyde (Preparation of a Precursor of a Bark-Beetle Pheromone)... 

The elm bark beetle pheromone contains three compounds multistriatin, the alcohol 12 and a-cubebene 13. At first we shall consider simple molecules like 12 but by the end of the book we shall have thought about molecules at least as complex as multistriatin and cubebene. 

This is the first of four General Strategy chapters in which we discuss important points that apply to the whole of synthetic design rather than one particular area. This chapter concerns general principles to help you choose one C-C disconnection rather than another. Even a simple molecule like the alcohol 1, introduced in chapter 1 as a component of the elm bark beetle pheromone, can be disconnected at any of the five marked bonds. 

Brand J. M., Bracke J. W., Britton L. N., Markovetz A. J. and Barras S. J. (1976) Bark beetle pheromones Production of verbenone by a mycangial fungus of Dendroctonus frontalis. J. Chem. Ecol. 2, 195-199. 

Seybold S. J., Bohlmann J. and Raffa K. F. (2000) The biosynthesis of coniferophagous bark beetle pheromones and conifer isoprenoids evolutionary perspective and synthesis. Can. Entomol. 132, 697-753. 

White R. A., Jr, Agosin M., Franklin R. T. and Webb J. W. (1980) Bark beetle pheromones evidence for physiological synthesis mechanisms and their ecological implications. Z angew. Entomol. 90, 255-274. 

Molecular biology of bark beetle pheromone production and endocrine regulation... 

Some early and obvious questions about bark beetle pheromone components concerned their origins are they synthesized de novo from acetate or derived from plant precursor molecules And are the biochemical reactions performed by insect tissues or symbiotic bacteria Ipsdienol and ipsenol are clearly monoterpenoid alcohols. Since de novo monoterpenoid biosynthesis was unprecedented in the Metazoa before 1995, and monoterpenes are produced by host trees, it seemed logical that monoterpenoid pheromone components were derived from ingested plant precursor molecules (reviewed in Vanderwel and... 

Beyond the obvious demonstration that bark beetle pheromones are synthesized in midgut tissues, two other conclusions can be drawn from these studies. First, all the cells in the midgut are involved in pheromone production, since the... 

While classical molecular and biochemical techniques have provided useful insights into the regulation and production of bark beetle pheromone components, two important questions remain What are the biosynthetic steps between geranyl diphosphate and the final pheromone component (either ipsdienol or frontalin) And how is JH III acting on pheromone biosynthetic cells ... 

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