Olive fruit fly

Synthesis of Haptens and the development of an enzyme-linked immunoassay (ELISA) for the olive fruit fly pheromone, Bactrocera oleae has been reported. 

In particular, the importance of chirality in diverse pheromone systems has been reviewed recently (Mori, 1998). For example, olive fruit flies (Bactrocera oleae) emit racemic 2 the males detect the R enantiomer, while females detect the S (Haniotakis et al., 1986). The sex pheromone of the Osaka beetle (Anomala osakana) is 4a, while the closely related Japanese beetle (Popilia japonica) uses 4b (Table 16.1). Interestingly, 4a is a powerful behavioral antagonist in P. japonica (Tumlinson et al., 1977). The hemlock looper, Lambdina fiscellaria, responds only to (5R, 1 S)-5,I I -dimethylheptadecane. The enantiomer or the R/R or S/S diastereomers do not elicit electrophysiological or behavioral responses (Li et al., 1993). Table 16.1 gives an overview of those species where proteins from the pheromone olfactory system have been identified. 

Two important spiroketals, such as l,7-dioxaspiro[5.6]undecane (29a), the major component of the olive fruit fly (Dacus oleae) sex pheromone (Baker et ah, 1980 Fanelli et ah, 1983), and ( )-2-methyl-l,7-dioxaspiro[5.6]dodecane (29b), a component of pheromone of Andrena haemorrhoa (Bergstroem et al., 1981 Katsurada and Mori, 1984), have been prepared in a cascade process from polyfunctionalized nitroalkanes (26) (Ballini and Petrini, 1992). 

The enantiomers of olean were bioassayed in Greece by Haniotakis el a/.136 Surprisingly, (R)-116 was active against males, whereas (S)-116 was active against females. GC analysis on a chiral stationary phase of natural olean by Schurig revealed it to be ( )-116.136 Thus, the female-produced sex pheromone activates male olive fruit flies and the female herself. This is a very unusual stereochemistry-pheromone activity relationship, and is beyond our imagination. 

There are also many other types of compounds (11.33) used by insects other than Lepidoptera as sex pheromones. The methyl esters of L-valine and L-isoleucine are used by the cranberry white grub,157 periplanone B by cockroaches, ipsdienol by bark beetles,158 and dean by the olive fruit fly 159 jsocoumarjn is part 0f trail pheromone of the ant, Lasius fuliginosus.160... 

The cnol ether 4 was also converted into the pheromone (7) of the olive fruit fly by reaction with dimethyldioxirane to provide a very unstable epoxide that rearranges to the ketone 6 on treatment with CSA. Reduction of 6 with NaBH4/CcCl1 provides the pheromone 7 as a 13 1 mixture of epimers. 

The synthesis of (2 5, 6R, 8 S)-2,8-dimethyl-l,7-dioxaspiro[5,5]undecane (868), one of the spiroacetal components of the pheromone isolated from the olive fruit fly, hinges on a dialkylation of tolylmethyl isocyanide with bromide 866. The bromide is obtained from 845b by sequential reduction of the olefin and ester followed by conversion of the resulting alcohol to bromide. Acidic hydrolysis of dialkylated product 867 provides the pheromone 868 directly... 

C,H, 02, Mr 156.22, bp. 73 °C (4.0 kPa) (25,5R)-iso-mer [a] -100° (hexane) (2S,5S)-isomer [a] r%° (hexane). Aggregation pheromone of bark beetles of the genus Pityogenes. Males of P. chalcographm excrete this spiroacetal as a mixture of the (25,55)- and (25,5/()-isomers to attract males and females of the same species to colonize a host tree. Only the (25,5/ )-isomer has an attracting action which is dramatically increased by simultaneously excreted, extremely small amounts of methyl (2E,4Z)-2,4-decadienoate (C, H,g02, Mr 182.26). Isomers of C. are the pheromones conophthorin and olean, the sexual attractant of the olive fruit fly Dacus oleae. C. is currently the economically most important pheromone with a market value in 1995 of ca. 20 Mio. DM for its use against forest pests. 

A neat approach (Scheme 37) to the spiroketal 213, a component of the pheromone of the olive fruit fly, involves a base-catalysed oxy-Michael addition between ketosugar 210 and 211 to give stereoselectively the adduct 212, convertible as indicated to the target. ... 

Olive fruit fly (Sactrocera oieae) Mediterranean fruit fly Ceratidscapitata)... 

An interesting correlation is observed in the case of clean, the pheromone of the Olive fruit fly. Whereas in males only the (fl)-enantiomer carries activity, the female, which produces the racemate, responds to both antipodes - also as a self-stimulant. 

The Olive fruit fly (Bactrocera oleae) originates most likely from the Mediterranean countries, where infestations have been reported even in BC times. The pest spread further to South Africa, across the Middle East to Pakistan and northern India. Since 1998, also olive plantations in California are threatened (Fig. 8.86). The pheromone of the Olive fruit fly is olean, aspiroketal (1,7-Dioxa-spiro[5.5]undecane). 

Both the (R) and (S)-isomers of spirobi-I,4-dioxan, (28) and (29) respectively, which are dioxa analogues of the olive fruit fly... 

Pheromones are important organic compounds in agriculture because they represent one means of baiting and trapping insects that may be harmful to crops. Olean, the sex pheromone for the olive fruit fly, Dacus oleae, can be synthesized from the hydroxyenol ether shown by treating it with a Brpnsted acid (H-A). 

Interestingly, even natural products that contain a spiroacetal as the only stereogenic element are known [52]. The parent 6,6-spiroacetal is also a natural product, olean, the major female-produced sex pheromone of the olive fruit fly (Scheme 18) [53]. Although it has been isolated from natural sources as a racemic mixture, it was found that its two mirror enantiomers display a remarkable sex-specific property. The (/ )-enantiomer is active on males and the (S)-enantiomer on females of the olive fruit fly [54]. 

Scheme 18 Two enantiomers of olean from olive fruit fly...

The two isomeric compounds below are naturally occurring insect pheromones. The isomer on the left attracts the male olive fruit fly the one on the right, the female, (a) What kind of isomeric relationship exists between these two structures (b) What functional group is contained in these molecules (c) Both of these compounds are hydrolyzed under aqueous acidic conditions. Draw the products. Are the product molecules from the two starting isomers the same or different ... 

Another dipteran species described to host AAB, namely Acetobacter trap kalis, is the olive fruit fly Bactrocera oleae, an appreciable pest that affects olive... 

Another interesting situation is the olive fruit fly (Bactrocera oleae). The female produces the sex pheromones J -olean and S-oleanasdrawninFigure4.10 [19]. The J -olean excites males, and the S-olean excites herself One final example of the amazing variety of ways in which insects use chirality is the... 

Preparation of (4S,6S)-4-hydroxy-4,9-dioxaspiro[5.5] undecane (47), a pheromone component of the olive fruit fly. 

Asymmetric hydrolysis of acetate ( )-46 with a spiroacetal ring system was achieved with pig liver esterase (PLE) to give alcohol (4S,6S)-47 and the xmreacted acetate 4R,6R)-46 (Figure 24.24) [28]. The alcohol (4S,6S)-47 is a component of the sex pheromone of the olive fruit fly. 

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