ChemInform Abstract: Chiral Building Units from Carbohydrates. Part 13. Identification of the Absolute Configuration of endo‐Brevicomin from Dendroctonus frontalis and Synthesis of Both Enantiomers from D‐Ribose.

Abstract

The title compounds (‐)‐(XII) and (+)‐(XVI) are prepared starting from D‐ribose via the key intermediate (VII) (in part no yields given).

Evidence that (+)-endo-Brevicomin is a Male-Produced Component of the Southern Pine Beetle Aggregation Pheromone

“…Our findings and those of Redlich et al (1987) both indicated that the (+)-enantiomer was predominant, and both studies were performed by using MSD chromatograms of single, diagnostic ions for endo-brevicomin. This procedure would have largely ensured that only the target molecule was quantified and would have prevented overestimation of the abundance of (-)-endo-brevicomin because of coelution of compounds indistinguishable by FID alone, as could have occurred in the study of Grosman et al (1997).…”

“…However, VitC et al (1985) also showed that (-)-endo-brevicomin is an attractant antagonist, and there are conflicting data on the enantiomeric ratios of endo-brevicomin produced by D. fiontalis males. Redlich et al (1987) found approximately 97% of the (+)-enantiomer when they used enantioselective capillary GC-MS to analyze aerations and hindgut extracts of emergent male D. frontalis. Grosman et al (1 997) used enantioselective GC-FID to analyze gut extracts from emergent males from three different populations and reported a range of 9-21% (+) with no significant variation among regions.…”

“…First, conflicting evidence exists regarding the enantiomeric composition of endo-brevicomin (Redlich et al 1987;Grosman et al 1997), hence the relative amounts of the apparently repellant (-) and the attractive (+)-enantiomers produced by D. fiontalis is uncertain. Second, addition of male D. ji-ontalis to female-infested pine bolts failed to alter responses of conspecifics Svihra 1982), suggesting that male-produced semiochemicals neither inhibit nor enhance aggregation during host colonization.…”

Semiochemicals in the Natural History of Southern Pine Beetle Dendroctonus frontalis Zimmermann and Their Role in Pest Management

“…Since production of endo-brevicomin has been shown to be stimulated in callow adult D. frontalis males by exposure to juvenile hormone II or its analogue methoprene (Bridges, 1982), it appears that pairing or mating may induce production of juvenile hormone in males. Male D. frontalis have been reported to produce 3% (Redlich et al, 1987) and 9-21% [newly emerged beetles from Texas and the Carolinas, United States (Grosman et al, 1997)], of the (À)-enantiomer. However, studies by the author and collaborators using enantioselective GC-MS have failed to detect the (À)-enantiomer in any hindgut or aeration sample of solitary or paired D. frontalis males, including paired males from Alabama, United States, and Chiapas, Mexico, as well as newly emerged, solitary feeding, or paired individuals from Mississippi, United States (Sullivan et al, 2007b, author's unpublished data).…”