Dihydroactinidiolide, a pheromone component of the red imported fire ant

The red imported fire ant (Solenopsis invicta) is a widely distributed pest in the southern USA. There exists a queen-recognition pheromone of S. invicta, which attracts worker ants, and causes them to bring inanimated objects treated with queen extracts into their nests as if they were real queens. One of the 

The hydroxy ketone B was converted to C, whose hydrolysis and iodolactonization followed by removal of the THP protective group yielded a separable mixture of two iodolactones D and E. The former (D) furnished ( -dihydroactinidiolide (89 ), while the latter (E) afforded (R)-89. Bioassay of our synthetic 89 and 89 by Dr. Tumlinson proved (7 )-89 as the bioactive pheromone component, and (.S )-89 was biologically inactive. 

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