Revision of the structure of the major aggregation pheromone of the broad-horned flour beetle (Gnatocerus cornutus) to (1S,4R,5R)-alpha-acoradiene by its synthesis.

(1S,4R,5R)-(+)-alpha-acoradiene [1,8-dimethyl-4-(1-methylethenyl)spiro[4.5]dec-7-ene] (1) is shown by its synthesis to be the major component of the male-produced aggregation pheromone of the broad-horned flour beetle (Gnatocerus cornutus).