title: Determination of chirality in 5-hydroxy-4-methyl-3-heptanone, the aggregation pheromone ofSitophilus oryzae (L.) andS. zeamais Motschulsky.
abstract: The chirality of the pheromone of the rice weevil,Sitophilus oryzae (L.), and the maize weevil,S. zeamais (Motschulsky), 5-hydroxy-4-methyl-3-heptanone, was determined using an acetyl lactate derivatization procedure. Maize weevils were shown to produce >98% 4S,5R. Determination was more difficult with rice weevils due to a smaller quantity of insect extract, but they were shown to produce at least 92% 4S, 5R.The attractancy of the four synthetic stereoisomers of 5-hydroxy-4-methyl-3-heptanone was tested using rice and maize weevils. As expected, both species were most strongly attracted to the 4S, 5R enantiomer. Maize weevils also showed low but significant responses (P < 0.05) to both 4R, 5R and 4S,5S. Rice weevils showed a highly significant (P < 0.01) response to 4R, 5S, although it was only about one third the response to 4S, 5R. Thus, (4S,5R)-5-hydroxy-4-methyl-3-heptanone is clearly the major component of the pheromone of bothS. zeamais andS. oryzae.
authors.affiliation: Stored Products and Household Insects Laboratory Agricultural Research Service, U.S. Department of Agriculture, USA.
authors.forename: C A
authors.initials: CA
authors.lastname: Walgenbach
authors.forename: J K
authors.initials: JK
authors.lastname: Phillips
authors.forename: W E
authors.initials: WE
authors.lastname: Burkholder
authors.forename: G G
authors.initials: GG
authors.lastname: King
authors.forename: K N
authors.initials: KN
authors.lastname: Slessor
authors.forename: K
authors.initials: K
authors.lastname: Mori