Deuterated analogues of 4,8‐dimethyldecanal, the aggregation pheromone of Tribolium castaneum : synthesis and pheromonal activity

To elucidate the deuterium isotope effect (DIE) in pheromonal activity and to investigate the biosynthetic pathway of 4,8‐dimethyldecanal (4,8‐DMD; 1 ), the aggregation pheromone of the red flour beetle ( Tribolium castaneum ), deuterated analogues of 4,8‐DMDs ( 2 , 3 , 4 , and 5 ), were synthesized and their pheromonal activities were tested using a two‐hole pitfall olfactometer. Although no apparent DIE was observed in their pheromonal activities, 4,8‐DMD‐ 1‐d 1 ( 2 ) was less attractive than other analogues, which suggested that the bond distance between the formyl group of 1 and its receptor was critical in pheromone recognition by T. castaneum . Copyright © 2004 John Wiley & Sons, Ltd.