Scolytus multistriatus

Sn2 Reactions with epoxides and aziridines are also synthetically useful. An example of epoxide cleavage with an organocopper reagent with sp carbon moieties is the enantioselective synthesis of (3S, 4S)-4-methyl-3-heptanol (53), an elm bark beetle (Scolytus multistriatus) pheromone [42]. The chiral epoxy oxazolidine 51 [43], prepared from (R)-phenylglycinol, reacted with a propylmagnesium bromide-derived cuprate at —70 °C to afford the oxazolidine 52 in 74% yield (Scheme 9.12). Compound 52 was converted into the target molecular 53 by conventional procedures. 

Often related insect species are not all sensitive to a particular allomone. For example, juglone is a feeding deterrent to the smaller European elm bark beetle (Scolytus multistriatus) but not to the closely related hickory bark beetle (Scolytus quadrispinosus) (106,107). 

Magnoline Inhibited feeding of bark beetle (Scolytus multistriatus) 439... 

B) Western balsam bark beetle, Dryocoetes confusus formation of endo-brevicomin [(1 F ,5S,7S)-7-ethyl-5-methyl-6,8-dioxabicyclo[3.2.1 ]octane] from ( )-6-nonen-2-one (Vanderwel et a/., 1992a) (C) Spruce beetle, Dendroctonus rufipennis formation of frontalin [(1S, 5fl)-(-)-1,5-dimethyl-6,8-dioxabicyclo[3.2.1]octane] from 6-methyl-6-hepten-2-one (Perez ef a/., 1996 Francke etai, 1995 Francke and Schulz, 1999) (D) European elm bark beetle, Scolytus multistriatus hypothetical formation of oc-multistriatin [(1 S,2F ,4S,5F )-(-)-2,4-dimethyl-5-ethyl-6,8-dioxabicyclo[3.2.1]octane] from 4,6-dimethyl-7-octen-3-one (Francke and Schulz, 1999) and E The colored... 

Blight M. M., Henderson N. C. and Wadhams L. J. (1983) The identification of 4-methyl-3-heptanone from Scolytus scolytus (F.) and Scolytus multistriatus (Marsham). Absolute configuration, laboratory bioassay and electrophysiological studies on S. scolytus. Insect Biochem. 13, 27-38. 

Elliot W. J., Hromnak G., Fried J. and Lanier G. N. (1979) Synthesis of multistriatin enantiomers and their actions on Scolytus multistriatus (Coleoptera Scolytidae). J. Chem. Ecol. 5, 279-287. 

Gerken B., Grtine S., Vite J. P. and Mori K. (1978) Response of European populations of Scolytus multistriatus to isomers of multistriatin. Naturwissenschaften 65, 110-111. 

Gore W. E., Pearce G. T., Lanier G. N., Simeone J. B., Silverstein R. M., Peacock J. W. and Cuthbert R.A. (1977) Aggregation attractant of the European elm bark beetle, Scolytus multistriatus, production of individual components and related aggregation behavior. J. Chem. Ecol. 3, 429 446. 

Mori K. (1974) Synthesis of (15 2R 45 55)-(-)-a-multistnatin the pheromone in the smaller European elm bark beetle, Scolytus multistriatus. Tetrahedron 32, 1979-1981. 

S, 4S)-4-Methylheptan-3-ol is a component of the aggregation pheromone of the elm bark beetle Scolytus multistriatus. It is readily synthesized from the (s) pinanediol ester of propylboronic acid as shown in Figure B6.2. 

The terpenoid-exocrine theme emphasized by scolytid beetles was again evident when the chemical constitution of the secondary attractant for the smaller European elm bark beetle, Scolytus multistriatus, was elucidated. The aggregation pheromone was identified as a mixture of (-)-4-methyl-3-heptanol, 2,4-dimethyl-5-ethyl-6,8-dioxabicyclo [3.2.1]octane (multistriatin) (XXII), and (-)-a-cubebene (XXIII), a host-derived synergist (70). All three compounds are required for the maximum attraction of beetles. The inactive diastereomers of 4-methyl-3-heptanol and multistriatin did not inhibit the responses of airborne beetles. 

Such a sequence has been successfully used115 for the synthesis of 4-methyl-3-heptanol, the major constituent of the aggregation pheromone of the elm bark beetle (Scolytus multistriatus Marsham)117 and zir-butyM-methyltetrahydro-2-furanone118 known as quercus lactone or oak lactone. ... 

Application of the preceding strategy to multistriatin synthesis (Scheme 11.26) started with compound 7, which was deoxygenated at C3 and further elaborated to ketone 106 [49]. Wittig methylenation provided 107, and subsequent double bond reduction using Wilkinson s catalyst afforded the dimethylated compound 34 [93]. Further manipulation yielded a-multistriatin 108, the pheromone of Scolytus multistriatus. Other syntheses of this pheromon from sugars have been reported [48,94,95]. 

Bark beetles. Insects related to the weevils that bore into the wood and bark of trees and often cause extreme economic damage to forests. Many species live in symbiosis with fungi the elm bark beetle Scolytus multistriatus transmits the feared elm tree disease caused by the fungus Ceratocystis ulmi. Some B. species are controlled by the application of synthetic pheromones in trap devices, that contain combinations of pheromones with synthetic insecticides see also bre-vicomin, chalcogran, conophthorin, frontalin, ipsdienol, lineatin, multistriatin, pityol, sulcatol, seudenol. 

Enantiomeric composition of a pheromone is instrumental with respect to the behaviour mediating capacity of the signal. This especially stands for bark beetles (Coleoptera Curculionidae, Scolytinae) where even different populations of the same species employ pheromone of different enantiomeric composition (Seybold, 1993 Miller et al., 1996). Enantioselective production of, and response to pheromones has been demonstrated in many species of Scolytinae subfamily (Birch, 1984 Borden, 1985 Byers, 1989). Electrophysiological studies have revealed that species such as Ips pini Say, 1. typographus (L.), I. paraconfusus Lanier, Scolytus multistriatus (Marsham), S. scolytus (F.) and Trypodendron lineatum (Olivier) and many others have olfactory receptor cells specific to optical isomers of aggregation pheromones (Mustaparta et al., 1980,1984 Wadhams et al., 1982 Tommeras et al., 1984). 

Kennedy, B. H., Effect of multilure and its components on parasites of Scolytus multistriatus, J. Chem. EcoL, 10, 373-385 (1984). 

That microorganisms in the gut of an insect are capable of converting substances from food plants into chemicals which can be used as pheromones has been demonstrated by several authors. Thus while Pearce et al. 171) reported that a// Aa-cubebene (11) one of the components in the aggregation pheromone released by Scolytus multistriatus, is produced by the host. Brand et al 172) found that a bacterium isolated from the gut of Ips paraconfusus converts alpha-pintnQ (12) to cis- and trans-wQvhQnol (13, 14) and myrtenol (15). 

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